2G Need help 97 eclipse gst High Idle

[DSM NE]

Ok so my 2g has been accelerating by itself while idle sometimes up to 2,300 rpms I’ve done a boost leak test and it wasn’t that if anyone could help me out throw some ideas I’d appreciate it

 

[2Gjunkie]

Ok so my 2g has been accelerating by itself while idle sometimes up to 2,300 rpms I’ve done a boost leak test and it wasn’t that if anyone could help me out throw some ideas I’d appreciate it

Auto or m/t? When you say “idle” you mean with your foot off the gas your car starts rolling up to 2300rpm? Or when in neutral the car idle rises to 2300rpm?

 

[DSM NE]

When parked sitting on neutral or when at a stop sign in 1st the car will rise on its rpms by itself and stay like that then out of nowhere like 2 minutes after it will go back down but even if on the highway once slowing down the rpms will stay stuck at like 1700

 

[2Gjunkie]

Is it a quick jump in rpm, or more gradual? Are you stock, or have you changed your OEM idle settings?

 

[DSM NE]

It’s a gradual build up it was tuned by someone in my local city and I went to oriley and advanced auto parts and they told me it was my o2 sensors but and employee told me it might be the tps sensor

 

[Sjd6795]

Try to measure your voltage on the TPS at idle.. It should be around 0.63v. Does the cars idle raise when the car is cold or does it only do it when it's operating temp?

 

[DSM NE]

When it’s cold

Another thing I should add my air fuel gauge jumps a lot now like from 10 to 28 when it’s set to 14.7 only while actually driving wil it kind of get stable from 13 to 17

 

[Sjd6795]

Get a profile created with all the information on your car, modifications, tuning device, maintenance, etc.. It will be much easier to assist with diagnosing.

 

[DSM NE]

Ok will do

 

[spyderdrifter]

If your car is manual, then I see your likely problem being you have severe idle surge, that is in turn causing your car to move due to clutch drag caused by improper measurements on your pressure plate. Also, while occasionally helpful, parts store employees are not always knowledgeable enough.

 

[DSM NE]

I mean o Riley and advanced auto part scanner said it was the o2 sensors also the car drives fine it’ll get stuck sometimes at like 1500 rpms and sometimes will rise a little bit also I cleaned my egr and iac valves and now my car dosent pull as good the turbo dosent have the same punch/kick as it used to the car is tuned and I have a apexi airflow converters it was also tuned idk if me cleaning the valves affected the tune

 

[DSM NE]

So today I got the car back from the shop after water pump changed along side the tps sensor and harness and yet it still rises in rpms.

another thing to add when putting in neutral is when the car mainly rises in rpms what could it be when I switch to 1st or 2nd it’s fine once it’s in neutral it rises.

I’m loosing patience and money guys please any suggestions are more then welcomed I just want the car to be in good shape to drive also look at my profile to see mod list if that helps I’ve also replaced iac valve and cleaned egr valve also 02 sensor needs replaced it’s the downstream one or b2 sensor 2

 

[motomattx]

Did you even try to adjust your biss screw?

 

[DSM NE]

Yep only took the rpm down by like 200 when it was at 1400 although it is pretty worn and torn it’s super super dry so I’m ordering another one and hopefully that will help

Also how far in does the screw need to be?

 

[motomattx]

It can be as far in as it needs to be to get you where you want, have you confirmed that you have no vacuum leaks? there's only so many things that will cause a high idle like that.

 

[DSM NE]

So far from what I’ve checked it doesn't also I had a mishimoto radio fan blow tons of fuses and because I kept trying even though the connections were wrong I wasn’t aware at the time could the ecu of been damaged? Also could cold weather affect it and my oil pressure light switch is cut and the oil pressure switch is damaged also my air fuel ratio can’t find a Balance it’s almost always at 25 does that also affect it

 

[motomattx]

None of that stuff would really affect it as far as the blown fuses, oil pressure light, etc, if your air fuel ratio is off thats an indication of a air leak somewhere to me, unless your afr gauge is not a true wideband or is not a good one. Is there enough play in your throttle cable?

 

[DSM NE]

It’s an aem wideband/gauge and I haven’t checked the throttle cable also I took it to o Riley’s and an autozone as well as advanced they said it was the o2 sensor but it was the one by the downstream so the one beneath the car not the one in front apparently it needs replacing could that be it?

 

[motomattx]

No, neither of your o2 sensors will cause an idle issue, the rear one is for emissions only and the front one is just there to trim the fuel during cruising for fuel mileage and proper air fuel ratio.

 

[DSM NE]

Wait but then why does my car backfire and smell really rich?

And stings my eyes

 

[DSM NE]

Welp I cleaned iac replaced tps and harness also cleaned egr didn’t help man also getting a new biss screw because old one was bad shape should I adjust tps since it’s new?

How would I fix that?

 

[DSM NE]

I’ll post a video tomorrow and link you it hopefully that’ll make it easier to diagnose thanks for responding man I appreciate all of you guys trying to help out

 

[DSM NE]

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There’s the video my tps isn’t adjusted and I’m pretty sure one of my gaskets ain’t good

 

[DSM NE]

Also is my gauge fine like this for the boost? It was in neutral not moving

 

[DSM NE]

No, neither of your o2 sensors will cause an idle issue, the rear one is for emissions only and the front one is just there to trim the fuel during cruising for fuel mileage and proper air fuel ratio.

It was the fiav in the end which is now deleted thanks for the reply’s much appreciated.