Jump to content

idle surge damnit


88lx5oh

Recommended Posts

Your car idel surges becasuse it's ideling too high and car sees a lean condition (more air, no more gas cuse your not steping on it), it puts more fuel in causing the idel to go even higher. The car realizes your rpm's are too high without the throtel and backs the fuel off, but then your back to the lean condition causing the constant loop. So basicly you have extra air geting in that's not supposed to.

 

clean out your throtel body and whatever 'valves' are in the throtel body too as best you can. Sometimes carbon will biuld up on where the throtel sits and will cause it to not shut all of the way leting extra air in. Whaever your car uses to idel too (idel control steper motor or something to that affect) can be dirty or damaged). Carb. cleaner works well to do this, just make sure you clean it up pretty well before you start the car back up.

 

I did thoes first and then I adjusted my biss (base idel set screw), there's an extra port that goes through in the throtel body (I think) in dsm's. I just adjusted it till my idel was where it was supposed to be. It's been totally fine after that. It had been geting worse and worse so I was afarid that it was something slowly going bad, maybe leaky egr (ISC's usually fail quick like), and it would come back again, but it never did.

 

Can also be extra air geting past a leaky egr (if your car still has one). You can try to quickly fab up something, maybe out of a piece of sheet metal, that can act as a temp egr. block off plate. And if that fixes it, you can get a real egr block off plate (hell, you might even be able to take yours off, not real sure how your ECU would react to that).

Link to comment
Share on other sites

Holbick that shit happened to Craigs car all the time on the old motor. It would drop to like 500 rpms, then surge to 1,000...over and over again. No big deal, just annoying.

 

Sorry I don't know what caused it. 5.0L's are notorious for it though. :confused:

Link to comment
Share on other sites

Join the conversation

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

Guest
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...