Crank no start 1988 Chevy C1500 5.7 350 tbi

Slade88

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Truck was running fine after the cam swap it idled smooth and revved smooth, everything was working properly and I didn’t wipe the cam, it was lacking power on the road that I now know was a incorrectly set transmission cable and never setting proper advance timing.



I decided to try and repair a slight drip on my passenger fuel pod, so I pulled the fuel fitting housing and put an improperly fit o ring on it.



I also removed the old plugs and put in new accel header plugs only tightening them hand tight but making sure they were seated.



The engine will not start, but will at some times and idle extremely low for a couple seconds before sputtering out.



I figured it might be the o ring I put on the fuel fitting so I removed it.



This fixed nothing.



I then disconnected the fuel line to make sure my fuel pump was working, it getting plenty fuel pressure and fuel sprayed out the fuel line.



I also filled my truck with more gas to make sure that wasn’t the issue.



I then figured maybe something is stopping up my TBI unit so I took it off and cleaned it out with carb cleaner as best I could.



This fixed nothing.



I then figured it may be the spark plugs because those were the only other noticeable change I made to the engine.



I replaced them with the same type of OEM plugs I pulled from the truck, they were already pre gapped to .40.



This fixed nothing.



I decided to check if I was getting power to my TBI wires so I attached a noid light and it confirmed that I’m getting a pulse to both injector wires.



I found no burnt fuses or fusible links.



I checked both injectors with a 9 volt battery to make sure the solenoid inside was clicking, they both checked out.



After I start the truck and put my finger inside the throttle body I can feel lots of gas that’s getting sprayed out.



I’ve tried spraying starting fluid in the intake and it doesn’t seem to have any effect.



Right now the only thing I can think this to be is possibly spark plugs wires not being on all the way, the spark plugs not in all the way because I only tightened them hand tight until I could turn anymore and they appeared to be all the way in. Or the TBI not spraying enough fuel for whatever reason.



It is worth noting after this cam swap I never set advance timing, and I disconnected the battery when I changed the spark plugs, so perhaps that wiped some data on the computer preventing the engine from starting?



I am at a complete loss right now, not having my vehicle on the road for a month has been an absolute detriment to my life and any help would be greatly appreciated. I diagnosed my first simple problem after my cam swap and now I have another issue preventing me from setting my timing and getting this POS driving again.
 

PlayingWithTBI

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It is worth noting after this cam swap I never set advance timing, and I disconnected the battery when I changed the spark plugs, so perhaps that wiped some data on the computer preventing the engine from starting?
Disconnecting the battery will wipe out your short term (INT) and long term (BLM) fuel trims. That shouldn't bother anything with starting. It looks like you're getting fuel and starting fluid doesn't help. What about spark? Do you have an HEI spark tester? How old is your ignition coil, cap, rotor, pickup coil, ICM, plug wires? Did you get your wires back in the correct firing order when you did your plugs? Are all the connectors going to the coil, ICM, and ECM connected and in good condition?

You can ball park your timing by cranking, with the black/tan EST wire disconnected, and a timing light. Then, once you get it running, fine tune it when warm.

How about compression? Did you set your lifter preload properly? If they're too tight, it won't start either.
 

Slade88

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Disconnecting the battery will wipe out your short term (INT) and long term (BLM) fuel trims. That shouldn't bother anything with starting. It looks like you're getting fuel and starting fluid doesn't help. What about spark? Do you have an HEI spark tester? How old is your ignition coil, cap, rotor, pickup coil, ICM, plug wires? Did you get your wires back in the correct firing order when you did your plugs? Are all the connectors going to the coil, ICM, and ECM connected and in good condition?

You can ball park your timing by cranking, with the black/tan EST wire disconnected, and a timing light. Then, once you get it running, fine tune it when warm.

How about compression? Did you set your lifter preload properly? If they're too tight, it won't start either.
Yep set preload when I did the cam swap and it started up immediately even after I let the engine sit for a couple days after I broke in the cam. Distributed and rotor and cap are all original. Everything is connected but I’ll give it a once over to make sure when I get off work as well as check to make sure I’m getting visible spark and fuel. I’ll try and set timing as well. Most everything on this engine is OEM original from the factory. Firing order is correct as well
 

Schurkey

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Distributor rotor still sitting on the workbench?

Verify spark at the spark-plug end of the plug wires using a spark tester calibrated for HEI. I prefer this kind, but there are other designs.
www.amazon.com/Performance-Tool-W86553-Ignition-Tester/dp/B003WZXAWK/ref=sr_1_1

xc_hide_links_from_guests_guests_error_hide_media

Spark TO the spark plugs means nothing if the plugs are fuel-fouled from cranking but not running. Be sure the new plugs are clean and dry on the firing tips.
 

Slade88

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Disconnecting the battery will wipe out your short term (INT) and long term (BLM) fuel trims. That shouldn't bother anything with starting. It looks like you're getting fuel and starting fluid doesn't help. What about spark? Do you have an HEI spark tester? How old is your ignition coil, cap, rotor, pickup coil, ICM, plug wires? Did you get your wires back in the correct firing order when you did your plugs? Are all the connectors going to the coil, ICM, and ECM connected and in good condition?

You can ball park your timing by cranking, with the black/tan EST wire disconnected, and a timing light. Then, once you get it running, fine tune it when warm.

How about compression? Did you set your lifter preload properly? If they're too tight, it won't start either.

Im getting spark and fuel, just checked
 

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