egr system question

[dheavychevy38]

Ok i have a 91 k5 with a 5.7 tbi. When you take off from a stop sign or light the truck backfires and bucks horrible. It through the check engine light and it says the egr system. I am going to do a tune up and replace the egr any other ideas thanks Denny.

 

[HarryH3]

Before you spend $50 on an EGR valve, remove the one that's on there and check to see if it has some carbon on the end of the pintle. If it sticks open, even a little bit, the engine will not run well. It might be something that you can clean up with a can of carb cleaner.

 

[dheavychevy38]

yea thats what i was thinkin i am going to yank it off after work today and check the carbon out see if the port is built up along with the egr. Thanks for the reminder.

 

[84zz4ss]

Also check the egr solenoid and it's vacuum source at the base of the throttle body. The passage can get clogged up and restict vacuum to the solenoid.

 

[dheavychevy38]

Ok so i didn't get a chance to mess with the egr yesterday but the code it through to day was a 32 which is a vaccum error. On the egr their is only one hose going from the egr to the solenoid. Then their is a tab underneath of that connection is their any pics of where this should go Thanks denny,

 

[dyeager535]

If you are talking about the EGR solenoid, there are only two vauum lines running to it, (source and EGR) but there is another nipple that is usually covered by a small foam block, which is just a vent. If the foam comes off, it looks like a hose is not connected where it should be.

 

[dheavychevy38]

when i looked earlier their was only one hose going to it

 

[GEORGIA GABE]

im not sure if it is what is happening to your truck or not but if you fix what sounds like a vacuum leak and it still runs poorly at takeoff but gets better as you get up to speed you should disconnect (temporarally) the egr vacuum and plug the line. go drive it and see how it does. If it drives alot better then what happened is the spring inside the egr valve was weak and it was opening up too quickly. Just a thought. good luck with it.
gabe

 

[dheavychevy38]

Thanks i will try that to night i made sure i had good flow through the vaccum line from the tbi to the solenoid. Is their a was to check the solenoid to see if it is working properly. If i tap on the egr it gets better for a while.