86 k5 engine problem HELP!!!!

[rodney chambers]

i have had this 86 k5 for a week. been drivin it to work and all has been good. on the way home from work tonight it died just like you turned the key off. i let it set approx 20 min. and it started and run for about 10 minutes. had a buddy come and get me, went home got tools and went back. blazer started right up and never missed a beat. so whats up with that???

 

[Grim-Reaper]

Choke

Sounds like the electric choke is not opening.

 

[rodney chambers]

it does take a while for the choke to kick off on cold mornings. do ya think it is just flooding out?

 

[Wingnutt]

Sounds like a bad ignition module if memory serves correctly. They tend to cut out when they warm up. They will run fine until they get warm then cut out just like turning off the ignition. Swap in a new one and let us know what happens.

 

[rodney chambers]

behind the glove box is the engine control module, could this be the problem. the reason i ask is the distributor has all new components including ignition module

 

[Grim-Reaper]

behind the glove box is the engine control module, could this be the problem. the reason i ask is the distributor has all new components including ignition module

The truck has ESC (electronic Spark control). The module above the glove box is part of that. Basically that controls ignition advance. the truck has a knock sensor and if it hear knock/ping it will retard timing. If it was totally hosed it could cause problems but I would expect those problems would be all the time not just when warm.


Choke not opening will flood th engine while its running.

So before you start throwing parts at it, like ig modules, do some diagnostics and take the air cleaner lid off and verify the choke is fully open after about 6-8 minutes. It shouldn't need more then that to be mostly open. Thats why the 10 minutes caught my eye and the sitting caught my eye. Its just the right amount of time for it to warm enough to flood out if the choke didn't open.

If you find it didn't open check for 12v at the choke WITH ENGINE RUNNING. if the engine is not running it will not have power. There is a oil pressure switch in line to the choke that cuts power if the motor stops running.


Also verify the preheat tube is hooked up and Thermac (the doohickey that controls the flap in the air cleaner) is functioning.

If its extremely cold where you are and the thermac is letting in all cold air you might be freezing up the carb. Also wouldn't hurt to run some line dry through it.

 

[mr.smartass]

you can take your ignition control module to your local parts store and they should be able to test it... that's what it sounds like to me and i know we can test it at the store i work for... just my 2 cents.

 

[rodney chambers]

i got up this morning and the blazer started right up..i let it warm up for about 5-10 minutes . just before i put it in gear i gassed the hell out of it. that is the only way it will idle down. it ran fine. when i came home this evening i did the same thing,and it ran like a dream. i guess the choke is not adjusted properly. what do ya think?