My truck stalls after it warms up?

[Checho187]

I have a 1993 gmc sierra sb with a 5.7 i recently got it like 1 month ago and it was running fine but now when it is cold it runs fine but when it warms up it stalls but will fire right back up but then stalls again after a minute or so if i give it gas it wont? Any ideas and also it will run likethat but shuts down when i come to a stop.

 

[kennythewelder]

Welcome to the forum. Love the strips. Very close to mine. There are a lot of things that can cause your truck to stall like that. The first thing to do is to do a code read. Here is a video on how to get your codes your self with a paper clip.

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[Supercharged111]

My 88 pulled that crap. It was a plugged fuel filter. High idle was enough to keep it alive, but once it warmed up and tried idling lower it was a no go. Had to stab the gas to keep it alive.

 

[Checho187]

Thanks guys i checked for codes and nothing. And i have replaced the fuel filter yesterday and still does it, i just took it for a spin and now notice it does it alot more. While driving you can feel it bug down then it comes back up then bugs down again or when it is parked and i give it gas the rpms go up then go down and goes back up its not steady if that makes sense lol

 

[kennythewelder]

How is your exhaust system, clogged up cats can do this. If the truck is running good at idle, but just has a lack of power, this could be the issue. This is just one of the things to check

 

[Checho187]

Well like i said it is fine when its cold once it warms up and i rev it thats when it starts bugging down then it will eventually stall. So i have no clue whats going on

 

[Checho187]

Could it be the fuel pressure regulator?

 

[Supercharged111]

It could be, that'd be the same as my filter being plugged. Have you checked your pressure? TBIs love to not have enough pressure.

 

[kennythewelder]

If it only does this once it warms up, that makes it hard to pin point. It could be fuel pressure, spark, or vacuum, it is hard to say. A fuel pressure check will tell you if it is in the fuel system. I look at the engine running at night, in the dark, can let you see a miss fire that you can not see in the day light, and a propane torch (unlite) passed over the vacuum lines and intake of a truck at idle can make any vacuum leaks show by the RPMs speeding up the engine from idle.

 

[Checho187]

If it only does this once it warms up, that makes it hard to pin point. It could be fuel pressure, spark, or vacuum, it is hard to say. A fuel pressure check will tell you if it is in the fuel system. I look at the engine running at night, in the dark, can let you see a miss fire that you can not see in the day light, and a propane torch (unlite) passed over the vacuum lines and intake of a truck at idle can make any vacuum leaks show by the RPMs speeding up the engine from idle.

Thanks i will check this