Jump to content

Low erratic idle


Recommended Posts

Truck battery was disconnected for about 2 days. When hooked back up truck wouldn't idle right. Low idle just below 500RPM and will stumble if you don't keep feathering the gas.


WIll be pulling codes on Monday but any rough guess on where to start. I would think MAF but it was fine before battery pull and then not fine after. Truck is stock less flowmasters cat back.

Link to comment
Share on other sites

Copied this from another post. Sounds like the same issue though...



Senior SS Member

  • Gender:Male
  • Location:Clarksburg, WV
  • Owns:SS
  • Color:Arrival Blue
  • Year:2003
  • Drivetrain:AWD

Posted 19 November 2015 - 12:52 PM

Sounds to me like it just needs to do an adaptive idle relearn. I'd try unhooking the battery again for about 30 minutes, then hooking it back up. Start the engine, and bring it up to temp. and then shut it off. Start it back up and put it in drive until the fan cycles on and off (5 minutes or so), then turn it off again. Wait 5 seconds, then start it and let it run for another 5 minutes. Then shut it off, wait 5 seconds and start it again, and it should be good to go. A dead battery shouldn't do anything to the tune itself.


If you don't go through that procedure, it will even itself out after a while. It's just annoying with the idle surging and acting like the engine wants to stall out in the meantime. I'm not sure the extent of the affect it has on power under a load, but it may have something to do with that too. I'd try that and see if it helps. Best of luck.

Link to comment
Share on other sites

Thanks. Had the codes pulled this today and their is a MAF Code. Concurrent to that the truck is slipping between 2nd - 3rd. Spoke to good tranny shop and was told to change the MAF and that should solve the tranny issue. They see this regularly. The MAF sets the line pressure in the tranny particularly for that shift. When accelerating easy the tranny shifts normal but if you step into it a bit then it will slip. They've save a few people a tranny rebuild or replacement.


He said also this only works if you have a Eng Light i.e MAF Code. No Code then probably the tranny is going.

Link to comment
Share on other sites

  • 3 weeks later...

Installed a new MAF. Appears to have solved the shifting problem. Idle problem was still there. Removed and cleaned the Throttle Body (highly recommend one takes some deep breaths while removing the TB. Not difficult per say but a pain in the backside. Fracking hose clamps bottom of the TB then trying to remove the hoses).


Anyway cleaned the TB which was gunked up pretty good. Everything seems fine now idle wise anyway. Still have eng chk light. It's for an EVAP Circuit. Changed out the EVAP Valve located top front right corner of the gas tank, didn't fix the light. More to follow.

Link to comment
Share on other sites

  • 2 weeks later...
  • 2 months later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...