The 1947 - Present Chevrolet & GMC Truck Message Board Network

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)
-   The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=4)
-   -   1987 TBI K5 No spark (https://67-72chevytrucks.com/vboard/showthread.php?t=830721)

edflores 02-07-2022 12:37 PM

1987 TBI K5 No spark
 
I Bought a 87 k5 350 tbi. Was running at a very high idle ( 2200-2700rpm). Previous owner put on a rebuilt TB. Checked everywhere for vacuum leaks. Found one at the TB base.Still high Idle. Performed TPS relearn. Idle dropped significantly but still a bit high.
Test drive and it dies as soon as you put it in gear. Would sometimes struggle even if you kept it alive, sometime ran like a beast.

I decide to do a tune up. I was advised to do a new distributor.
Replaced distributor, Coil, plugs and wires.
No Spark.
I have replaced ignition modules. Nada
Another new coil. Nothing.
Whole distributor again. Nothing.
I did the test on GM manual and I keep getting bad coil or module.

Injectors are firing while cranking so pickup/ecm seems good.

Only other thing that caught my eye was my dash volt gauge reads low most of the time. like 8 volts. Even if It gets to 12, it drops down very low while cranking.
I still have 12v at the coil though

Any thoughts or ideas?

Pano 02-07-2022 10:02 PM

Re: 1987 TBI K5 No spark
 
I have an 87 GMC with a 350 TBI. Several years ago it just died and had no spark. I replaced the distributor, rotor, coils and a few other things.

Finally I replaced what I think I remember is the ignition control module. It is near the distributor, under it or in it. It is small and has a 2 wire connector. Started right up.

Sorry, just reread your post and saw you replaced the ignition module. I do think the 2 wire plug needs to be oriented correctly for it to work. I don’t remember if it was keyed, but worth a look.

Just call me Sean 02-08-2022 07:58 PM

Re: 1987 TBI K5 No spark
 
Did you try putting the old distributor back in?


All times are GMT -4. The time now is 04:53 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2026, vBulletin Solutions Inc.
Copyright 1997-2025 67-72chevytrucks.com