Please help with high idle!

[purpleesi]

over the course of the last 2 days we installed the walbro 255hp, Aeromotive AFPR, ACT 2600 clutch, and ACT X-ACT streetlight flywheel.

my question is this: after all of these parts we installed i noticed that my idle was very high. It ranges from 2000 to 2500rpm all the time. It did not do that before these parts were installed. We turned the idle set screw all the way down and it didnt help.

Anyone know how i can fix the high idle? The fuel pressure is set to 45psi right now, should we turn it down, would that help?

Thanks

 

[mirkoelek]

over the course of the last 2 days we installed the walbro 255hp, Aeromotive AFPR, ACT 2600 clutch, and ACT X-ACT streetlight flywheel.

my question is this: after all of these parts we installed i noticed that my idle was very high. It ranges from 2000 to 2500rpm all the time. It did not do that before these parts were installed. We turned the idle set screw all the way down and it didnt help.

Anyone know how i can fix the high idle? The fuel pressure is set to 45psi right now, should we turn it down, would that help?

Thanks

i have the same problem dude , hope you feel better. I'm sure there are some people that will help us . It happend to me after i put fidanza flywheel , clutch and dsm link

 

[armandovivoni]

fuel pressure should be 38-40psi.

maybe Im sure you removed the fuel rail, did you replace injector O-rings? spill water on top on the injectors(were they seal, and notice if there is any change in rpm) if there is you got bad O-rings

 

[Attack Eagle]

I can tell you positively that it is not the clutch and or flywheel that is causing it... I actually had to BUMP my base idle UP afterwards.

I am sorry that i have not run across this issue before but it does sound like an air leak of some sort post t/b... you don't have a vacuum hose off still do you?

 

[evolvingGS-t]

Did you by chance mess or move your throttle cable out of the way to get to some parts?

 

[lauj2gdsm]

man... i have the same problem too... but it only start as soon as my car gets hot... i also tried to adjust biss screw too and other stuff but nothing. dang i hope some one has a cure for
us....

 

[sickgsx-316]

same thing happened to me when i did the same mods. I leaned out my afc quite a bit at idle and that helped out a lot...sometimes...

on occasion and out of nowhere it will just hop right back up to 2k-2.5krpm though. especially when its smog time, or im next to a cop, or any inopportune time. Silly DSMs.

 

[1SloColt]

I had this problem for about 2 weeks now and went through every possible avenue to finally cure the problem. First off, start the car, and see where the rpms are at and then turn on your headlights. If the rpms drop slightly and you hear some compensation then at least your ISC motor is working so thats a plus. Also, plug in your logger and check the tps at idle. Should be between 9-11%. If its not then there are two legitimate possiblities. Stuck or over tightened throttle cable and/or TPS needs to be readjusted. Check the throttle first. My cable was getting stuck in the sleeve of the linkage. Completely shut the throttle with your hand and see if the rpms fall. Re-correct the linkage if necessary. If your tps is still too high then you can ultimately adjust it so it reads lower by moving it to the left some. There is also a idle speed control switch but its actually just a bolt with a terminal on it which I messed around with some but it did not have any baring on my idle issues, which it probably won't with yours. A lot of times its just a stuck throttle cable. Also, pull up on the gas pedal with the top of your foot to see what that does. I also know that some people run without an ISC so that they adjust idle through BISS, which is kind of a pain in my opinion but if nothing else works then you might want to give it a try. I tried it and my car idled terrific that way just too high for my liking, right around 1100rpm with the BISS all the way in.

 

[purpleesi]

What ive noticed from driving it around today is that when i first start it up the idle is close to normal (about 1000rpm). After driving it a few miles it goes to 2000rpm, and if i continue to drive it longer, it gets up to 2500rpm.

At the same time my fuel pressure seems to drop after i have had my car off for awhile. So when its been sitting the pressure is low, as well as my idle. Then when i start driving my pressure goes up and my idle goes up too. That why im wondering if i should turn the pressure down a little.

i will try those suggestions though, and keep you posted on how it turns out.

Thanks

 

[howie3]

This happened to me, only I didn't do the mods you did, I put on a uicp and 1G bov. After I did that my idle was high I turned down the biss screw and nothing. There is a set screw for the throttle body and I found that it wasn't adjusted right (the throttle plate was open a bit), I adjusted the throttle body and even had to back out my biss screw because the idle was to low. Remember my idle was fine before the mods to and for some reason worked with the stock setup but not for the things I did to it Who knows there DSM's Good luck.

 

[mirkoelek]

if any of you guys solve this problem let me know please

 

[WICKEDTEEN84]

on a cold start does it idle that high? mine didnt idle that high intill i started driving a little bit. then on the next cold start when it didnt rocket up to 2,000+rpm. i just unpluged the iac and it idled fine thats just my 2 cents tho no problems since

 

[jb95gst]

I had this problem and lived with it for like a year before getting it fixed. I had the dealer look at it after I ran out of ideas, and they did not know either(who would have though ) but it ended up being the throttle cable. I had adjusted it before and the dealer adjusted it. I went in and added about 1/2 inch of slack on the adjustment bracket that is mounted to the intake manifold. Thanks to a local DSMer where I lived, that solved my problem and hopefully it will help all of you.
JB

 

[mirkoelek]

I had this problem and lived with it for like a year before getting it fixed. I had the dealer look at it after I ran out of ideas, and they did not know either(who would have though ) but it ended up being the throttle cable. I had adjusted it before and the dealer adjusted it. I went in and added about 1/2 inch of slack on the adjustment bracket that is mounted to the intake manifold. Thanks to a local DSMer where I lived, that solved my problem and hopefully it will help all of you.
JB

can you send me some pictures to show me what you did , it would be greatlly appriciated

 

[jb95gst]

Yeah, I will try to take a couple pics of it tomorrow to show what I am describing. I'll try to describe in words for the time being though. It is a bracket that holds the throttle cable and is mounted to the intake manifold. It is two 10 or 12mm bolts that bolt it to the manifold. If you loosten them and slide the bracket to side to loosten the cable.
I will try to get the pics of it and get them on here asap. Hope that helps some,
JB

 

[adidas5482]

I had this same problem for the longest time. It seemed that the longer I drove my car, the higher the idle was. Finally I replaced both tb gaskets and my idle was cured. Don't use rtv sealant here, just buy new gaskets and torque the tb bolts down good and tight.

 

[kvx]

Yeah, I will try to take a couple pics of it tomorrow to show what I am describing. I'll try to describe in words for the time being though. It is a bracket that holds the throttle cable and is mounted to the intake manifold. It is two 10 or 12mm bolts that bolt it to the manifold. If you loosten them and slide the bracket to side to loosten the cable.
I will try to get the pics of it and get them on here asap. Hope that helps some,
JB

I have been having this exact same problem for a week now. It I fixed it this way too. If you have a pocketlogger/DSMLink look at the throttle position. That is how I figured it out. It started idling high after I changed my injectors. I guess I bumped the bracket and knocked it out of adjustment.

 

[GVR4592]

I'm not sure if you guys are just turning the biss screw without following the proper procedure, but none of you mentioned grounding out the two connectors to put the ecu in idle adjustment mode. VFAQ has a writeup on how to do it properly. Make sure your throttle cable is not binding anywhere. I dont know where you heard that the tps should read 9-11% that just doesnt seem right to me. Mine always reads 4%. It has read that on all 4 of my dsms.

I would set the fuel pressure properly first. 38 psi on a 1g 43 psi on a 2g. Then adjust the idle following the steps in vfaq. Then adjust the timing while your at it because high timing can give you a higher idle. Make sure that you do not have your datalogger plugged in, or the connector under the dash grounded, when you adjust your timing or it will not work properly. Make sure you dont have any vacuum leaks, that will mess with your idle too. I think i covered most of the major points everybody feel free to point out anything I missed.

 

[1SloColt]

From my experience with dsms and from the current extensive amount of research I have performed over the last couple of weeks on dsm idling characteristics it is concluded that a majority of well idling dsms idle at a mean of 10% tps. If you need any links concerning the information with which provided my conclusions I will be happy to PM them to you.

 

[Attack Eagle]

I'm not sure if you guys are just turning the biss screw without following the proper procedure, but none of you mentioned grounding out the two connectors to put the ecu in idle adjustment mode.

lucky for him he has a 95... 96+ don't have the connectors you describe.

 

[purpleesi]

Well we got the problem fixed today. First we noticed that we had forgot to tighten one of the bolts all the way on the throttle body. So we got that pretty snug. Next we noticed that the throttle cable was bent a little too much to the drivers side of the car, so we bent it back the other way and that seemed to solve the problem.

Thanks for all the help guys, im glad it was an easy fix...ive spent enough money in the last few weeks to last me awhile.

 

[jb95gst]

Sorry I didn't get these pics earlier, but today was a hectic day. Hope these help, let me know if there are any more Q's.
JB

 

[mirkoelek]

thank you guys, two bolts that was the problem. i fixed and its ok now