overreacting about my idle?

[d347644]

I've been trying to fix my screwy idle for a while now and have come to the realization that maybe it isnt as bad as im thinking. It will start up and idle fine and even when its warm itll idle good, the problem im having is coming to a light or a stop. If I sit at a stoplight for a while my engine might decide to surge a little and if I dont give the throttle a quick snap itll eventually surge worse until it dies. Itll only happen after about a solid minute of sitting. But the thing is, if I let it sit out front its fine, hell itll idle for 20 minutes no prob. Is the problem im experiencing have to do with my computer learning its idle startegy? I hardely get to drive my car and it seems im resetting my kam every few days, lol.

let me know what you think, because honestly this is my first hipo car ive built with a cam and am still learning what to expect with driveability and idling.

thanks

Drew

 

[86bluecobra]

there is a link in the tech section of the 5.0L tech that show you all the things to do with the idle. odds are the iac is dirty or your tps is giving the computer the wrong volts or you just have a really dirty throttle body.

 

[86bluecobra]

http://forums.stangnet.com/showthread.php?t=534062

 

[d347644]

ive gone through 3 tps sensors and tested their readings using my pms, all checked good. Ive gone through 2 iac's with no change in idle characterstic. The point of my thread if seeing if I really have an idle issue. Like I said, it idles fine but has trouble after a minute of sitting at a light.

 

[86bluecobra]

that definetally is a idle issue. sometimes a dirty tb can cause this because it isn't closing enough. since the egr feeds close to the butterfly valve many tb get gummed up. just for giggles why don't you remove your air intake and open the butterfly and check the inside of it. then remove it and clean ot with tb cleaner. it will dissolve all the gunk that has formed on it.

 

[HISSIN50]

I agree about going through Jrichker's sticky.

Info about your car would help (since you mention a cam).

Good luck.

 

[d347644]

I have stage 1 cam, tw heads, 1.6 rr, edel performer intake. 70 mm tb, 75mm pro m...

thanks

 

[86bluecobra]

is it a maf car or a maps computer control?

 

[onefstsnake]

be careful when cleaning the TB.

If you can I would take it off the car. My TB had a sticker on it saying not to clean it...

Well I found that out after I sprayed it down with Brake Cleaner...
Must have got into the combustion chamber, b/c the stuff smelled horrible.

I have a strong stomach...and I almost puked.

 

[HISSIN50]

I wasnt sure what to expect mod-wise and I'm not great with that stuff, but if you have exhausted the normal things folks do to try and fix such an issue, it might be tune/handheld time.

 

[d347644]

I am running mass air setup with pms handheld. all harnesses in my 86 are from a 91 gt.

 

[Euphoric306]

whyd you clean your tb with brake cleaner?

lol i use the carb/choke cleaner and it doesn't smell at all

 

[legalize420]

i have the same problem. solid idle, but the rpms hang when coming to a stop. i remember reading on here that the vechile speed sensor keeps the idle up while coming to a stop so that the car does not stall.

 

[d347644]

well see my idle wont hang but itll start to drop like 150rpm and then bounce back up and like I said earlier that rpm change sometimes leads it to surging and itll die. This only happens after like a minute of sitting and it always happens when im out driving on the street!! never happens on my driveway or anything, lol.