Evo 9 idle problems

[vanousad]

Hey all, I am having an Idle problem with my Evo 9.

When I coast to a stop at a stop light my idle drops to around 400 RPMs (a couple times it stalled out). When I let the car warm up before driving it the car runs fine, it's after i've been driving it for about 5-10 minutes when it starts acting up. Every once in a while when I coast to a stop the RPMs bounce from 400 RPM to 1.1k RPM several times before it settles back down at 900. At first I thought it was a vacuum leak, but my friends think it may be a O2 sensor going out.

Can anyone else help me determine what the problem is? Thanks in advance.

[Massimo Power]

Evos tend to have problems with the idle air control valves... People get problems like you and also some people get the RPM stick when the rpm stays at one point for a few seconds before dropping even after the clutch was disengaged.

It might have to do with mods such as an intake or a VTA BOV... it might also just be a dirty Idle air controld valve...

[vanousad]

Evos tend to have problems with the idle air control valves... People get problems like you and also some people get the RPM stick when the rpm stays at one point for a few seconds before dropping even after the clutch was disengaged.

It might have to do with mods such as an intake or a VTA BOV... it might also just be a dirty Idle air controld valve...

I have the stock BOV and no intake work done yet. Thank you for the advice, I will try and get the air control valve checked out. As for the RPM sticking, yea mine does that too. I was told that was normal though for Evos.

[gsrIXevo]

Hey Massimo... could this also be linked to just having cams and not adjusting the idle to run a little higher (for guys that like to run AC at stop lites) or could it be because of the seals in the TB going out?

I know most ppl report a boost leak if the seals on the TB are going out... but I wanted to see what others think before I start researching the wrong thing...

[silvrEVOIXn818]

I have the exact same issue right now... Been doing it for a while now... It just randomly decides to drop down to ~ 500rpm for me, @ a light (doesnt stall/hasnt yet) and bounces back up to normal... I also have had the throttle hang after putting it into nuetral after a pull... I would love to figure this ish out... Its starting to irritate me...
The onlything I can think of is a boost leak/'s. I have checked the Vac lines, all plumbed in, the egr clip is in, MAF clip is on tight... And this is W/ OUT the AC on...

I thought I might need to adjust the BISS, but that wasnt the issue, for me...

[baylorar]

I have the exact same issue right now...Â* Been doing it for a while now...Â* It just randomly decides to drop down to ~ 500rpm for me, @ a light (doesnt stall/hasnt yet) and bounces back up to normal...Â* I also have had the throttle hang after putting it into nuetral after a pull...Â* I would love to figure this ish out...Â* Its starting to irritate me...Â*
The onlything I can think of is a boost leak/'s.Â* I have checked the Vac lines, all plumbed in, the egr clip is in, MAF clip is on tight...Â* Â*And this is W/ OUT the AC on...

I thought I might need to adjust the BISS, but that wasnt the issue, for me...

I have all these same problems as well.Â* From what I remember, the idle stepper tables need to be modified.Â* Do some searching of 'throttle hang' on evom and you'll find a couple of huge threads discussing it.

[silvrEVOIXn818]

O0

[baylorar]

if biss = idle stepper tables, i apologize haha

[Massimo Power]

Hey Massimo... could this also be linked to just having cams and not adjusting the idle to run a little higher (for guys that like to run AC at stop lites) or could it be because of the seals in the TB going out?

I know most ppl report a boost leak if the seals on the TB are going out... but I wanted to see what others think before I start researching the wrong thing...

Yea thats one of the possibilities...well two.. lol

[Massimo Power]

I have the exact same issue right now...Â* Been doing it for a while now...Â* It just randomly decides to drop down to ~ 500rpm for me, @ a light (doesnt stall/hasnt yet) and bounces back up to normal...Â* I also have had the throttle hang after putting it into nuetral after a pull...Â* I would love to figure this ish out...Â* Its starting to irritate me...Â*
The onlything I can think of is a boost leak/'s.Â* I have checked the Vac lines, all plumbed in, the egr clip is in, MAF clip is on tight...Â* Â*And this is W/ OUT the AC on...

I thought I might need to adjust the BISS, but that wasnt the issue, for me...

I have all these same problems as well.Â* From what I remember, the idle stepper tables need to be modified.Â* Do some searching of 'throttle hang' on evom and you'll find a couple of huge threads discussing it.

Good lookin out.. O0

[anxiouz]

Did anyone mention if the car had cams or not? To me that makes a big difference in diagnosing this.

Warm car startups on hot days causes my idle to dip real low initially and then sometimes stall unless I give it some gas. After maybe 3 attempts to dip low it's all fine again. But it's only warm car starts.

[gsrIXevo]

I think this is the EDO Tomei test turbo car that had cams and other goodies if i'm correct. A list of parts would help to figure out what other parts could cause this issue.

[vanousad]

Ok sorry guys yea ill give you a list of things done.

Tomei PROTOTYPE M7960 turbo (soon to get production model)
Tomei Exhaust manifold
Tomei Down pipe
Tomei O2 housing
Tomei Headstuds
HKS hi-power exhaust
Blitz Electronic boost controller
Blitz turbo timer
WORKS Slotted rotors
WORKS Stainless steel braided brake lines
Hawk Blue race pads
WORKS Hi Flow air filter
WORKS 780cc Fuel injectors
Walbro fuel pump
Cusco Zero 2R coilovers
Excedy Stage 2 clutch and Flywheel
6 Glowshift gauges

No cams yet but they are coming as soon as I get a little more money.
The car started doing this before I got the clutch installed but it started getting worse after the install. I do know Logan accidentally pulled my oil pressure gauge sensor wire off so now my gauge bounces back and forth. They will fix that as soon as I bring the car in for the production M7960 turbo. I know this problem has nothing to do with the clutch but maybe he hit something else or pulled out a line that I cant see.

When my RPMs drop my oil light comes on for a split second. I checked my oil and I was a quart low so I added some and it took care of the oil light for a while. I am taking the car in to change the oil this weekend so I hope that helps keep it from starving itself.

[baylorar]

I have trouble with warm starts too. Cold starts were hard until I changed my dieing battery.

My rpm drop has never caused a light to come on, but i should just fix my car and post how i did it here ^-^

[myfastevo8]

I have the same issues , RRE told me they were 80% sure , not completely diagnose but said it was my ICV (idle control valve). I know eclipses have that comon problem....my evo is an o3 evo8 with like 75k or so. My syntoms are fustrating aswell. That little part is about $300. When I turn my a/c my car stalls right away. I dont know if the Valve has to do something with A/C.... can any one advise????

[sneakypete]

Hmmm, my car has idle issues and it's bad on 91 but only when I have the AC on.Â* It never occurred on e85 until this week and my temporary solution is to shut off the AC when I'm approaching a red light.Â* As soon as the rpm drops to the 900 range, I usually turn it back on.

I hope my upcoming re-tune fixes this issue.

I'm running cossie M3's which I'm sure makes things a tad more difficult.



SP

[vanousad]

I'll be honest with you guys, I didn't know a bunch of people were having this problem. I'm glad I posted about it. I am going to South Coast Mitsu on Monday so I will ask them what they think. I need to find out why my horn don't work, fix the brake calapers, and turn off my Airbag light. So while I'm at it I'll ask what the deal is with the idle and let you guys know what they say.

[silvrEVOIXn818]

if you go on evom, this is a somewhat, common prob.

myfastevo8, your issue w/ the AC on, sounds like the BISS needs adjusting... What rom ID? 96530006? This rom id is known for this issue! You might wanna put it into SAS mode and see where its at... Should be ~ 750. This is not the fix for me, or most of us, but for some, its as easy as that!
I think we all should check it, just to rule it out... O0

[CRONZ305]

I have this issue also been trying to find out why it does it.

Happens only when car has been driven for a whole or if I got on it hard.

Idle drops, afr gets rich then resumes.

[amaev05]

you have a aftermarket hard pipe intake?