Chevy 350 tbi timing off symptoms 

Chevy 350 tbi timing off symptoms. Check your fuel pressure 1st. A few weeks ago the original fuel pump finally croaked just shy of 200K miles. 12 Diagnostic Checking for operation of CEL bulb. Watch the rotor. (2 years ago) I put a crate motor in it and haven't had it running right since then. 7 L truck and after an oil pressure problem got Jan 8, 2021 · This cam is designed specifically for the TBI 350 small-block and specs at 194/214 degrees of duration at 0. Jul 20, 2023 · R1500. They can (and do) fail in a way that you can still have spark, but no signal to the PCM to ground the injectors. Revving seems normal. Now rotate the engine MANUALLY back and forth just a bit with the coat-hanger doing a "teeter-totter" on the edge of the spark-plug hole and watch your marks down below. It would stall while sitting at idle in park or when in gear at a stop sign. Hello all, Recently bought a 91 crewcab square with a 454 TBI with a 4l80e behind it, after vehicle has been shut off, after more then 30 seconds it won't restart, found injectors to not be pulsing on startup/spraying fuel. 14 Coolant Sensor Circuit Excessive HIGH temperature indicated. #1 · May 3, 2009. I have a '95 K1500 with a 350 that only sparks when it wants to. 7L 350, TBI, Auto, 220Kmiles Its been a great truck, for the most part it runs and drives great! but at low idle or low rpm's it missis,sputters,surges and if im just barely giving it any gas it almost wants to stall out. one other thing that may be worth mentioning, is that i eliminated the A. Jan 12, 2024 · Step 3: Affix The Timing Light To The Engine. Apr 7, 2023 · Yes i am diconnecting the tan wire behind passenger carpet and am trying using this method. Perhaps there was too much slack in the timing chain too, I'm not an expert though. The 350 TBI ignition system is a type of electronic ignition system used in Chevrolet 350 cubic inch (5. Its got a 350 TBI and I had replaced the intake on it and now i just need to set timing. Now to my next problem. Sometimes the coil will burn the pick up on top of the rotor. Distributor could be in a tooth off. Aug 12, 2019 · It s/b 9 - 13 PSI (according to GM specs), at idle and under acceleration, preferably 11 - 13PSI. B. Dec 4, 2011 · Timing light says spark is at 35 initial and 60 total off the crank. It will not reset the PROM to it's factory settings. AFAIK it is for 2 reasons. When starting with the wire connected it will crank and have multiple sudden stops in cranking, then sputter for a second and die. I have a 91 Silverado K1500 4x4, 5. Re: 88 350 TBI timing/ignition problem. Fire up the engine and using the idle adjustment screw somewhere on the throttle body, adjust the idle to where you want it. Truck sat for about 7 yrs and am getting it road ready for my nephew. But if it's not set correctly, it will run Feb 2, 2024 · The most common sign of a bad knock sensor is an illuminated check engine light. Most all stock TBI motors (light pickups) have very mild flat tappet camshafts with a lift of . You need to pull the dist. Good information to know when setting up the timing table. Dec 15, 2009 · Answered in 4 minutes by: GM Mechanic: Jerry Newton. #2 · Nov 4, 2009. It's my first GMC ever . In most cases starting out with 12 degrees of initial advance is about May 3, 2009 · G. There are no symptoms of overly advanced ignition timing, late cam timing, there is only Apr 4, 2012 · Your best bet is to get an adjustable timing light so you can just work off of your 0 mark. Dec 11, 2010 · Re: 350 tbi problems I wonder if the buzzing noise you hear is the spark jumping in an open coil wire (the wire between the distributor & coil) or a bad distributor cap or rotor. The distributor of the EST ignition system in 350 TBI engines does not have mechanical or vacuum Aug 14, 2004 · Most tbi's are set at 0 base timing (wire unplugged). Measure the vacuum level in the intake system with a Feb 21, 2007 · Re: 87 tbi 350 trouble. could be flakey. 7L. Oct 7, 2018 · Make sure that the ECM can recognize a fault code, tap the block near the knock sensor and see if the ECM sets a code or unplug the ECT in the manifold and see if the ECM sets a code. Once the engine gets to around 110-120 the rough idle/RPM hunting behavior begins. Remove the air cleaner assy, on the back passenger side of the engine there is a vacuum hose from the intake manifold that goes to a black, plastic "Y-type" vacuum check valve behind the distributor. Code 43 means the ECM has been low voltage at CKT 485 terminal "B7" for longer than 5 seconds with the engine running or the system has failed the functional check. didn't notice any difference in the truck so i kept on driving it for a few days (i know i know) and then i decided to look into it today and found it was giving codes 32 (EGR Failure) and 42 (ignition Oct 3, 2023 · Engine Size. Half the time it should be pointing at no. It's running great, starts easy, not pinging, not overheating, plenty of pep. On a TBI, most common reason for no fuel spray from the injectors - although there is proper fuel pressure - is a bad ignition module. I have a 1994 GMC Sierra 4x4 with the 5. This system performs a functional check once per start-up to check the ESC system. The timing/esc wire on a 90 Suburban would be in the area of the power brake booster. Oct 3, 2023 · Engine Size. The engine seemed to run fine while driving. – Fuel Injection: The TBI (Throttle Body Injection) system is used in the Chevy 350 Oct 5, 2012 · A 79 350 from an impala was rated about 150hp (maybe lower). 1582 posts · Joined 2002. Vehicle: 1995 Chevrolet K1500 stock 350 TBI; 153k miles. etc. It happened to me (among others) with a new Spectra Premium distributor within a couple 1000 miles. '70 CST Blazer, 350, SM465, NP205. there use to be a double vacuum line coming off the throttle body. Truck64, Nov 29, 2015. These trucks can start and run with a faulty ECM. plug in est wire. Adjust the timing light to find the total timing. what is happing is from time to time it falls flat on it's face with no spark from a stop light or at cruising Rotate the engine over until you see the exhaust rocker close, then keep going until you see the intake close as well. Check carb idle mixture settings same way. The result will be the engine running rough as unburnt fuel is pushed through the engine. The timing table I posted works great with stock flat tapped TBI camshaft I Aug 26, 2005 · The problem with trying to use the mv of the O2 while in closed loop is the ECM is designed to roll the AFR slightly from rich to lean constantly. 1986 Chevy G20 Tow Rig - 5. It's easy to determine where TDC is. Will die on acceleration, and only restart with WOT. Pry the clip off (ok if it breaks, new part comes with new one). #1. When letting off the throttle the engine would nearly stall with very low rpms (~400 Jan 7, 2016 · Another symptom of a problematic ESC module is the engine stalling. Engine Size. View Details. 454 TBI. K. Make sure your plug wires are not too funky. I currently am running at 8 degrees advanced with no issues. Last edited by ChevyTech; 02-21-2007 at 07:40 PM. Jul 16, 2012 · Backfiring through both the exhaust sounds like it might be cross fire. After 30 seconds unplug the IAC valve. May also want to check the spark timing. Advancing base timing even a couple degrees Feb 5, 2011 · 93 Chevy 350tbi runs but won't idle. Leaking Vacuum Lines. Now to the too much fuel. Pro Comp Programmer. Disconnecting the battery makes the computer dump the former timing so it can set it up new again. Disconnect the EGR vacume and plug the line. fire engine. 1) EGR control solenoid is being strobed for some reason. i will check it again with it connected and get back to you on that. Trouble Code. check the distributor pickup for shorting/intermittents. It controls the ignition timing and firing sequence of the engine. Aug 5, 2010 · i set the timing to 0 degrees with the bypass wire disconnected. It’s near the top usually on the back side of the harness. Jim. This ratio determines the efficiency of the combustion process and affects the engine’s overall performance. (Of course, they also fail in a way that won't allow spark. Now look at your rotor. Replaced: Distributor, Fuel pump, TPS, IAC, ignition coil, ESC, knock sensor, coolant temp sensor, O2 sensor, MAP sensor, ECM (reman). Disconnected spark advance and started up. www. 232 posts · Joined 2007. Code 43 means the ECM has been low voltage at CKT 485 terminal "B7" for longer than 5 seconds with the engine running or the system has failed the functional check. I think I have fixed almost all the random issues except one. 4: Throttle Position Sensor (TPS) wiring diagram. I would also replace the timing module int he distributor. 2-Bolt Mains. If Its a new engine, you need to recheck all the plug wires and fire order. Shut engine down, reconnect timing connector, and that's it for the timing. Sometimes the engine can still be restarted after a short period of time, usually after the module has been allowed to cool off. Jumper the A & B connections on the diagnostic link with a paper clip or what not. Hi, my 1993 Suburban was running fine one day and then the next day it starts acting up. 3:1. org. If you have bubbles, you either have a blown head gasket or cracked head or block. 7/auto, used short block with fresh heads installed 25K miles ago - those of you that followed the project may remember I replaced a ton of items as well to ensure its reliability. set timing to 0. NOTE: When testing the MAP sensor -. 060 over. 350. 2: Using a DVOM, backprobe terminals A and B of the TPS sensor to check for proper reference voltage. At the exhaust, the best way I can describe the sound is like "chuff chuff chuff chuff" However, I've pulled the plug wires one by one and it only gets worse, like a true dead cylinder. Jun 17, 2012 · Location. The distributor must then be grabbed, turned clockwise, and stopped when it is precisely in line with your eyes. Locate Timing Marks: Find the timing marks on the crankshaft pulley and the timing scale on the engine. It ran ok, but was in need of a tune-up. knock the roll pin out and pull the shaft to get at the clip that holds the pickup coil on. However alomst all TBI's can be timing from 4-8 degrees with better power. 442-inch lift. I've looked in all the forums and I find people with a similar problem to mine and have tried their fixes with no luck. When the PCM detects a problem with the knock sensor or its circuit, the module will turn on the check engine light and store a corresponding diagnostic trouble code (DTC) in its memory. This will cause an over heated condition when everything else checks out. 350 TBI engines also have ignition control module inside the distributor. It may be tan/black or tan/white. Rough-running engines will make a grinding or growling noise while idling and stutter instead of speeding up smoothly when . Timing at 0 degrees BTDC in bypass, but around 8 degrees at idle under control of the ESC. com 1‐888‐WESTER‐1 nwester@eidnet. Tilley, Alberta, Canada T0J 3K0. Shut down the engine and clear the codes in the Oct 7, 2021 · About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright Jun 15, 2010 · Start the engine and shine the flashlight down into the radiator. These engines are notorious for carbon plugging up the vacuum ports in the throttle body causing it to not get the correct vacuum signal to the map sensor. May 20, 2010 · If I remember correctly, when you hook the by-pass wire back up and recheck timing, it should be sitting on about 10 degrees advance. It will idle around 550rip'ems but it's pretty rough. May 3, 2023 · The ignition module works by using electronic components to switch the primary voltage to the ignition coil on and off rapidly. Got timing roughly set around 0. This misfiring only happens when the connector used to set the 'base timing' is plugged together. It has a hard time with ANY load (even the A/C compressor). Then plug the EST wire back in. 36 month/Unlimited Mileage Warranty. Take the distributor cap off, and have someone bump over the motor. Oct 7, 2013 · Electric choke is connected and working properly (choke blade closes when cold and opens when warm). The firing order for a Chevy 350 engine goes 1-8-4-3-6-5-7-2, which is the pattern that says which cylinder gets the spark from the distributor next. Jan 11, 2019 · I have a 355 small-block Chevy in my 1971 Nova and just swapped on a set of used aluminum heads. every thing to do with ignition is new, ie, cap, roter, coil, distributor, plugs and wires. The computer will next set up the timing scale. GTBjay Discussion starter. Bumping the base timing AND running higher octane fuel in order to prevent the detonation that advancing the timing causes, MIGHT gain you a small amount of power. I know you said you changed the AIC, but your symptoms are pointing to that, so I would waste the $15 just to be sure and change it again. then my friend told me that the time was off he tried to adjust it with the timing light but it seems like it got worse, after adjusting it and shut it off the truck wont start or you hear the starter hitting Mar 20, 2003 · Mar 20, 2003. is disconnected when checking timing and port plugged. Indicating. Feb 3, 2007 · I've spent countless hours trying to troubleshoot my 89 350TBI engine in my 240,000 mile otherwise incredibly dependable Suburban The engine runs like crap, ECM says code 44 - lean condition. Along with the erratic idle, the engine has absolutely zero power. 1. It would start and idle fine for a few minutes then the engine would die. you are correct on the timing marks pointing towards each other. Probably the quickest way, is to pull the cap off, turn the engine until the indicator is pointing at TDC, and see where the rotor is pointing. Reduced Engine Power: A bad knock sensor can cause your engine to lose power Feb 12, 2024 · Here are some key specifications of the Chevy 350 TBI engine: – Compression Ratio: The compression ratio of this engine is typically around 9. Feb 12, 2011 · Running very rich, down on power. Didnt know know if i had to disconnect Feb 5, 2016 · The timing can vary between 2 and 12 degrees BTDC, the recommended spark plugs are different and even the plug gaps vary. No power, struggles up hills, runs a little better at higher rpm's, won't climb a hill from a stop hardly at all. Dec 8, 2017 · Do you have a Chevy 350 (1955-1995) that just will not run right? Have you replaced the Carburetor, Distributor, plugs, wires, fuel pump, and filter too stil Aug 9, 2012 · 1994 5. to recheck timing after installation you will always rotate the crank two full turns (720deg) and make sure that the marks line up again. check under cap to see that it is pointing at #1. Old engine had 225k abused, hard miles on it. unplug the computor (tan/blk wire on the passenger side firewall) then run a timing light, set it at 0, and if it falls on its face on a full throttle start, advance the distributor about 5 degrees counter clockwise and test again. 386 (very likely to be the lowest lift cam GM used in the Chevy 5. O. There are several symptoms of a bad knock sensor in a 350 TBI engine, including: Engine Misfires or Hesitation: If your engine is misfiring or hesitating during acceleration, it could be a sign of a bad knock sensor. try a tap test on the ECM and see if it changes anything. Get some 64cc performance street heads and a mild RV type cam and you can double the power. Now, reconnect the vacuum advance and have a friend bring the motor up to 4000 rpms and hold it there. Ran better, but still stalled. It fires right back up very easily. 7 hesitation problem. 12-02-04 10:46 AM - Post# 566007. Reconnect the number one spark plug wire, if removed. 92 Silverado. Tracing that wire will reveal that it will contain a Sep 18, 2006 · 91 TBI 350 EGR problems. 5. Oct 22, 2008 · Big6ft6 Discussion starter. You'd really need to drive around with a graphing scanner in order to truly know if you've found the sweet spot. If the engine is running poorly do not expect a normal MAP sensor reading or voltage. MUCH better pump than the EP386 TBI pump. unplug EST behind passenger carpet. Thanks for the help. A faulty module may cause the engine to suddenly stall and be unable to start again. The ECM will retard the timing when knock is detected and RPM is above about 900 RPM. #1 · Oct 22, 2008. Compare to GM Engine 12703983. this is a factory setting. Long Block/Remanufactured. (24) Ships TomorrowEstimated to ship direct from manufacturer. I know your supposed to disconnect some wire, need to know where the wire is at. Why is a wiring diagram important for the 350 TBI ignition system? Apr 22, 2005 · I found the tan/blk wire as sone as I pulled off the glovebox, and it was obvious since it was wrapped by itself on the outside of the computer cables. Aug 26, 2009 · Hook up a manual gauge or read the map sensor (from the scan tool) when under load, idle etc. 3: Using the DVOM, backprobe terminals C and B of the TPS sensor, open and close the throttle and make sure the voltage changes smoothly. Apr 26, 2010 · Base timing with the wire unplugged is 0 or top dead center. ecmprogrammer. #10. 99. 7 TBI. A timing light is the easiest way to confirm if it's functioning correctly. If you have a vacuum leak at the throttle body to manifold, which is common, or anywhere else, that may be causing lean pops too. If a TBI motor is not at 0° you have problems with acceleration Aug 3, 2010 · Engine Size. Re: Setting timing on 350 TBIset to 0 deg but surging, wont run IMO, one of a couple of things. Problem with the ECM, bad EGR, bad valve, or bad vacume. I replaced the plugs, wires, cap, rotor, and air filter. 7 liter engine). I restarted the engine and drove it, but it would stall when I would come to a stop. A vacuum leak results in supplying the wrong air/fuel ratio into the engine, thus, resulting in bogging or rough and slow acceleration. Then you also make a good hint on a timing related issue. #1 and used oil excessively, like 1 quart every 600 miles. Houston TX. with the wire disconnected. SYSTEM. #2 · Apr 13, 2017. SHARE POST #7. Had a burnt valve in cyl. To get idle @ 900 rpm, the idle mixture screws are (1/2)- (3/4) from closed. Remove the old distributor cap and rotor by loosening the screws that hold them in place. The location of the connector should be listed on the emissions sticker under the hood. Stock jetting from factory. It is a single wire and has a black connector on it. R1500. Jan 19, 2024 · Spark Advance In 350 TBI Engines. If it doesn't turn at all, well you know what that means. 7 afr. disconnect battery. 350 . R. At idle in park, the engine revs up There are various actions you can take to attempt and fix the problem if your TBI-equipped car exhibits idle surge and stumble. 4. Just as syclone said the factory spec is 0. #3 · Jan 13, 2003. 7 TBI conversion 1978 Mustang II King Cobra Road Racer - Holley 650, MSD 6AL, 5 speed, 10 point Roll Cage, 9" posi, fuel cell, custom interior. Setting the Timing on a Small Block Chevy. 350 TBI Bad Ignition Module Symptoms. Remove and check this valve carefully. If the timing is not changing, except for centrifugal at higher RPM's I would suspect the ignition module. Pinging Noise From the Engine. If you ordered a pump for a TBI engine but are running V-belts, more than likely you have May 23, 2016 · Well, it didn't seem to idle rough until a few weeks after we bought it haha. 3 posts · Joined 2009. Truck Model. In order to do this, you need to disconnect both battery cables, and touch them together for 30 seconds, or so. « Reply #1 on: April 19, 2014, 01:16:06 AM ». I had to disassemble the front of the engine to get to the gears to reset them. Vac. Low compression, very poor heads, and a tiny cam. Check the fuel pressure. components. 88Silverado said: Mine was doing a similar thing. I pulled it apart, set the timing, turned off the truck, and reconnected it, and then the timing advanced almost to the end of the timing marks. 7 350 TBI. I have a timing light. I have a 87 Chevy R1500 w/ 350 TBI. 02/1. Oct 14, 2021 · The vacuum gauge is saying something is way off as the how far you need to set the timing from the marks. one line went to the egr and one went to the AIR valve. Next shut the truck down, disconnect the battery terminal for over a minute. 13 Oxygen Sensor Circuit No signal to computer. Find TDC. New valve seals didn't make a dent with oil consumption. #2 · May 11, 2001. 398/0. Watch on. but it runs great when accelerating or about Jul 18, 2009 · Make sure it's long enough so it can't possibly fall in. 351 / . Mileage down from 13avg to around 8. May 10, 2001 · Unknown member Discussion starter. Apr 21, 2024 · Figuring out firing orders for performance engines involves understanding the specific order that the cylinders fire in, which is crucial for the engine to operate properly and get the timing right. Re: Timing adjustment on \'94 Chevy. I have a 1991 K2500 with the 5. Aug 14, 2022 · The engine builder set the timing gears off by one tooth. 7L 350 TBI. It will idle perfectly fine and it also drives pretty good normally but on occasion it Mar 13, 2020 · We would double-check the part number for the water pump you installed on the engine if you still have it. Adv. There are two elements that need to be indexed these are distributor housing to a fixed point and the rotor toward the number one cap terminal. The timing will be set to 0 deg. This is the girlfriend's '93 C1500 5. On a TBI motor with Electronic Spark Timing, you unplug the Tan/black stripe wire next to the brake booster to disable the EST and time the motor to 0°. Nov 8, 2009 · Recently bought a used 92 Sub with 5. 2004 SILVERADO 2500HD LS. Check the vacuum lines. The 350 TBI engines have an EST (Electronic Spark Timing) ignition system. Crawling up inclines or slowly accelerating from green light or in parking lots, engine would stumble and sound like hell. Jun 15, 2004 · 1. The timing on a 91 is controlled by the ECM via the 8 pin HEI module. It does have allot of miles on it (275,000) but for the most part it runs like a clock. Nov 21, 2013 · Thanks for the reply. Yes, it is true. This sets the engine to TDC for the number one cylinder. Nov 13, 2006 · Nov 14, 2006. I replaced it with a Delphi pump and strainer Mar 14, 2018 · "new" used engine runs like a top, I've even got the timing set to 1 degree. If vehicle is started with starting fluid it will stumble to life slowly, then idle fine, will run Nov 29, 2015 · Here's how: With engine warmed up and idling at factory spec rotate distributor for maximum vacuum indication (advance timing) at idle RPM, and then back off (retard timing) 1" Hg from highest reading and tighten distributor hold down. Check Vacuum Lines for Leaks: A vacuum leak in the intake system is one of the most frequent causes of idle surge and stumble. reconnect battery. Check the dist reluctor and the top portion of the reluctor for rust at the dist shaft area. Put the 1996 Vortec EP381 pump back in. If it idles slow, poorly, or rough the vacuum will be lower which will make the voltage higher – out of the normal range. It should be between 32-36 degrees for premium gas 30-32ish for regular. Hello. Jun 1, 2023 · Top 6 Reasons Why Your Chevy 350 TBI Bogs On Acceleration. Fig. 1 to keep the cats happy since they don't like steady temps. Car not starting or engine not sparking. I can time the engine to 0 degrees with the ecm wire disconnected and it runs good at idle, however, when i turn the truck off, unplug the battery and connect the ecm wire, the timing just stays at 0 degrees and doesnt advance it like it The symptoms: The truck starts fine when cold or hot. Jun 7, 2019 · 350 tbi ecm not advancing timing. Alternatively, you may say, “Turn it to 12. K. #9. ”. Sep 25, 2018 · 1995 Chevy 350 tbi HELP!!!! Hey guys so I have a 95 Chevy Silverado that had a blown motor when I bought it. check the coil resistance values when warm. You have to time this correctly for it to run. Apr 19, 2014 · Re: Chevy TBI 350 stumbles on acceleration. 1968 Camaro RS. Jan 12, 2003 · 1. yes if you rotate one full turn the cam notch will be at that top as the cam turns at 1/2 speed , i have included Aug 16, 2009 · The computer will control your timing curve, using the information from the PROM in it. ) Sometimes a parts house module test Apr 12, 2017 · 4523 posts · Joined 2012. Nov 24, 2010 · 5. Apr 24, 2021 · Chevy Mechanic: camerontech. i bought a 91 GMC C1500 with a SBC 350 and i drove it for about 200 miles and then noticed the engine light came on. 15 Coolant Sensor Circuit Excessive Low temperature indicated. I. When it gets to operating temperature and the idle drops more it is more noticeable. If it turns with the motor but jumps a little bit when the starter is let off, the timing chain is likely gone or jumped a tooth. The problem I'm having is intermittently, 1-2 days a Nov 11, 2014 · I have a 1987 350 CID Chevy Silverado 1/2 ton that misfires something terrible when the motor is cold (approximately 50 degrees Fahrenheit and lower). Symptoms: Stumble/hesitation/chuggi ng on application of very slight throttle. Stick your finger over the number one spark plug hole and rotate the engine, if you get air coming out, then go ahead and set the crankshaft timing at zero degrees using the marks on the damper and timing cover. Here are some symptoms of a bad ignition If the fuel pressure drops more than 1 psi under 8-10 seconds of full throttle the pump should be changed and dont put the stock TBI pump back in even if your engine is stock. I recently finished up a rebuild on my 1989 C2500 TBI 5. Set Engine to Top Dead Center (TDC): Rotate the crankshaft pulley so the “0” on the pulley aligns with the “0” on the timing scale. '87 Suburban 4X4, 350, 700R4. I was wanting to know the right way to set the timing on my 87 C10 truck. 7 TBI motor. I have searched the forums and found similar threads but nothing seems to fix my problem. If vehicle is started with starting fluid it will stumble to life slowly, then idle fine, will run A worn timing chain that is still on its gears may cause the valves to open when the pistons are at the wrong point in their stroke. This is a common problem spot. Oct 5, 2008 · Something else to go on. There is a brown wire with a black tracer attached to the distributor module at the 4 pin connector. If there is a problem in the cap or rotor you will for sure see it. 7. This action causes a magnetic field to build up and collapse, inducing a high voltage in the secondary coil that fires the spark plugs. Yes, retarded cam timing can lower the values obtained during a compression test. Where is the knock sensor location on a 1989 350 TBI? :neutral: I put in a new engine and can't remember where the knock sensor goes, I know it was on the passenger side, but the hole in the passenger side head is too big for the knock sensor threads??? Dec 19, 2003 · If so the pickup coil is bad. New MAP, EGR, O2, TPS, ESC, distributor and coil. 7L 350 TBI Surging/Sputtering/Missing. As you can tell, it doesn't deliver Sep 27, 2022 · PlaywithTBI. I've seen multiple times the ICM (Ignition Control Module) will wig out once the engine warms up after a while (don't use Chinese junk parts). The timing chaim is out of the equation, degreed cam is out of it, a Tooth off, 180* off none of that matters. It stumbles as if it's missing a couple of cylinders when you accelerate. Small Block Chevy TBI 350 ci, 5. 1134. This could be the distributor off s tooth which is pretty common. You'll hear the IAC screw resetting. By just disconnecting the battery to clear codes. While cold with the idle still on the high side it seems smooth and normal. Jul 19, 2009 · Fig. For your 1991: The set timing wire is located, under the hood, on the main harness that goes from the engine to the firewall, on the passenger side, sometimes underneath the black plastic cover (if it’s still there) that covers the junction block, relays & fuses. Turn “OFF” the engine and remove the timing light. M21 4 spd. Replace the pickup and also check the magnets on the shaft, I have seen them crack. 285-75-16 Cooper ST All Terrains. Tighten the hold‐down bolt, and recheck the timing. But, it has no role when the engine is running at higher RPMs. 60 Nov 4, 2009 · DoubleVision. Maybe it starts now because when you replaced the distributor you moved something else enough for it to run. $2,599. Re: Setting timing on \'89 TBI 350. 7 liter) engines with throttle body injection (TBI). 2. I was told the heads have 180cc intake runners, 64cc chambers, 65cc exhaust ports, and 2. Dec 21, 2016 · It was set to zero when the truck started having these issues, since I have replaced the distributor, I have not used a timing light to get 0 again, but that's only because nothing has changed as far as symptoms. Problem is when I first start the truck in the morning (or after sitting awhile) and go to take off, it will chug, bog out, or barely go for a few seconds, then snap out of it and run fine. 11400 posts · Joined 2002. Installed stock rebuilt engine a few weeks ago. I recently rebuilt my 1990 k1500 350 tbi and upgraded to vortec heads. Watch it real close as the engine warms up to see if you have any bubbles in the radiator. In response to scott88. As mentioned above, if it's "backfiring" through the throttle body, odds are you're running lean causing lean pops. Reconnect the “Set Timing” connector. Some other symptoms to look out for to ensure that the problem is indeed a vacuum leak are hissing sound from the engine bay Apr 4, 2008 · The ECM will retard the timing when knock is detected and RPM is above about 900 RPM. Pro Comp Leveling Kit. Disconnect the timing connector, it's a tan/black single wire connector on the firewall. If you unplug the connector used to set the 'base timing', then the truck idles and runs just Feb 23, 2006 · Set the initial timing at 12-14 degrees if you're using premium gas 8-10 for regular. Here are a few potential answers: 1. so the ECM can continuosly adjust to the desired 14. This system performs a functional check once per start-up to check the ESC system. Plug the hose to prevent air leaks. Symptoms of a Bad Knock Sensor in a 350 TBI Engine. A. 3. Jun 2, 2008 · This weekend I put a new idle air control valve and o2 sensor in, and the symptoms still persist. Unplug all of the wires from inside of the cap as well. 050-inch tappet lift with 0. Sep 2, 2009 · Pop off the cap and look ar the rotor. Reconnect timing wire, reconnect battery terminal and start. Start engine, set timing to zero. Place your new distributor into position and secure it with its mounting bolts into place in order to ensure proper alignment and fitment. rf tu ak gp ng jn oq lw dy dm