Engine dies while idling. Starts right up.

bugeyed

Original poster
Member
Dec 25, 2011
78
3 or 4 times in the last year my truck has dies when idling at a light or in traffic. Seems that it only happens when the weather is warm & the AC is on. AFAIK the engine is always warmed up. I am wondering if it's related to the throttle advance when the AC comes on. Always starts right up & then runs fine & doesn't throw a code. Throttle body was cleaned recently & plugs are new. Am now running some injector cleaner through the system. The injector cleaner is just a what-the-heck-can't-hurt attempt, 'cause I would expect a code if it's related to fuel or ignition. Any insight is appreciated.

Thanks,
kev
 

gmac310

Member
Dec 4, 2011
174
I'm assuming you unhooked the battery when you cleaned the TB? If not, that could be the cause of your problem. I you did, check to make sure you don't have any vacuum leaks and that the big hose under the intake resonator is hooked up properly.
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
And did you do the full-up cleaning of the back side by removing it from the engine? Spraying in the front is thought of as a cleaning of other platforms, but our I6 has no PCV valve so it's the backside that gets gummy and stickies up the butterfly disk. Who did the cleaning and did you put in Delco 41-103 plugs? Sorry if this is all obvious to you and you already know how to do it right. But your symptoms are 99.94% indicative of a dirty throttle body, and the "clean the back while the battery is disconnected" is the miracle cure for that. :thumbsup:
 

bugeyed

Original poster
Member
Dec 25, 2011
78
Yes, I did the full TB cleaning off the engine with battery disconnected. That's been about 3 months ago though, with little mileage since. No, I didn't use the Delco plugs. I used NGK (read that they were equivalent & NAPA didn't have enough Delco):redface: & idle has been fine. That was the same 3 months ago too. I'll check the hoses, but it runs/idles great. Just those 2 times in 2 weeks most recently. Last time was last spring when the weather warmed up & was using AC. It gets hot here all summer, so I run the AC most of the year without issue. I had the battery disconnected again 2 weeks ago to do some stereo work, but unsure of the timing of the incident.

Thanks,
kev
 

ItsOnVoy

Member
Nov 21, 2011
2,401
Now I will have the same problem myself sometimes with the AC. Even after having my TB cleaned and injectors sprayed and all that good stuff. I say go buy a simple injector cleaner from any store really and put that in next time you fill up your tank and you should be all good to go. I do not know why but my truck does great once I put that stuff in. My truck also shut off in the middle of the road once from a stale even after cleaning the TB and all, my dad told me to just put the injector cleaner in and not a problem since then! Try that out, its a simple purchase and can do the trick
 

MacMan

Member
Mar 3, 2012
194
bugeyed said:
....I had the battery disconnected again 2 weeks ago to do some stereo work, but unsure of the timing of the incident......

Well, even though it's only been 3 months, I'd give the throttle body another cleaning w/ battery disconnected again. It's possible that it got a little dirty since the last time, and you reset the computer to "new" again when you did that stereo work.

As always, remove from the truck & do both sides.

May not be the problem, but can't hurt to try, and may be a simple fix.
 

Voymom

Member
Feb 3, 2012
2,523
I have to ask...

Do you happen to notice if the truck stalls as your starting to push the gas pedal?

I have a similar issue with my Envoy. It idles fine, however when I hit the gas pedal whether driving or idling the RPM's fall downwards before it accelerates causing a stutter/stalling feeling. My truck has stalled on me only once(Knock on wood).

I have yet to find the problem, but your not alone!
 

bugeyed

Original poster
Member
Dec 25, 2011
78
Voymom said:
I have to ask...

Do you happen to notice if the truck stalls as your starting to push the gas pedal?

I have a similar issue with my Envoy. It idles fine, however when I hit the gas pedal whether driving or idling the RPM's fall downwards before it accelerates causing a stutter/stalling feeling. My truck has stalled on me only once(Knock on wood).

I have yet to find the problem, but your not alone!

No, it's just idling in drive at a light or Taco Bell. I know for a fact it's not when I hit the pedal 'cause, the few times that it happened, I had time to restart it, turn down the stereo & rev it a few times before moving.

kev
 

Voymom

Member
Feb 3, 2012
2,523
bugeyed said:
No, it's just idling in drive at a light or Taco Bell. I know for a fact it's not when I hit the pedal 'cause, the few times that it happened, I had time to restart it, turn down the stereo & rev it a few times before moving.

kev

Okay, I just had to ask.

Now, it could still be your spark plugs. These trucks do okay for a little while with non OEM spark plugs but usually after a while the truck starts to act up and sometimes causes idle issues. I had non OEM spark plugs in mine when I bought it...truck had all sorts of problems. Switched to OEM ACDelco plugs and it purrs like a kitten. Just my 2 cents though.

I think my idle issue is a fuel filter/injector problem since it only happens when I hit the gas.
 

ItsOnVoy

Member
Nov 21, 2011
2,401
bugeyed said:
No, it's just idling in drive at a light or Taco Bell. I know for a fact it's not when I hit the pedal 'cause, the few times that it happened, I had time to restart it, turn down the stereo & rev it a few times before moving.

kev

I will have the same thing with that light idle once in a while. Try it out, put injector cleaner in and it should do the trick! its like $2-$3 or so for a simple one
 

bugeyed

Original poster
Member
Dec 25, 2011
78
Voymom said:
Okay, I just had to ask.

Now, it could still be your spark plugs. These trucks do okay for a little while with non OEM spark plugs but usually after a while the truck starts to act up and sometimes causes idle issues. I had non OEM spark plugs in mine when I bought it...truck had all sorts of problems. Switched to OEM ACDelco plugs and it purrs like a kitten. Just my 2 cents though.

I think my idle issue is a fuel filter/injector problem since it only happens when I hit the gas.





I know, I have felt guilty ever since I read that there is a big difference in the plugs. BTW I have read quite a few posts that say that some AC Delco iridium plugs are marked NGK on one side & AC Delco on the other. I will probably break down & replace them this summer.
 

Voymom

Member
Feb 3, 2012
2,523
bugeyed said:
I know, I have felt guilty ever since I read that there is a big difference in the plugs. BTW I have read quite a few posts that say that some AC Delco iridium plugs are marked NGK on one side & AC Delco on the other. I will probably break down & replace them this summer.

I don't know if my Delco's had NGK on them or not as I didn't make it a point to look. But I do know I had a bad engine power issue before we switched ours out. I felt like I was getting ran over by grannies in their granny-mobile's because my truck didn't want to get up and go at all. We did a few things maintenance wise plus changed the spark plugs and everything works just fine.

I hope you find out what's going on, I know just how frustrating these trucks can be, I had my truck less than 60 days and I had already changed a bad T-stat, water pump, power steering pump, and my fan clutch has been ticking. I do know we need to get a new pulley and so forth. I haven't had the Envoy that long, in fact I just made my second payment on it :crazy:
 

Forum Statistics

Threads
23,438
Posts
639,266
Members
18,655
Latest member
Jaywebb25