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2G Car idling really weird. Help plz, stuck at work.

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Echosyp

Proven Member
130
47
Oct 31, 2019
Clanton, Alabama
I got to work this morn and as I was pulling in the car starting spitting and sputtering. When I parked it was idling really rough and I noticed the factory boost gauge goes halfway up and stays there. When I give it some gas it goes up to about 3-4K rpm and just sputters really bad like I’m hitting rev limiter. Any ideas?
 
Any work recently done to the car? Assuming you have enough gas, first step is to check all your vac/boost hoses under the hood and make sure nothing cracked or came loose.

also check your plug wires to see if they came loose from the plugs or coilpack.
 
Last edited:
Any work recently done to the car? Assuming you have enough gas, first step is to check all your vac/boost hoses under the hood and make sure nothing cracked or came loose.

also check your plug wires to see if they came loose from the plugs or coilpack.

nothing done recently, had the car since last Nov and haven’t done anything to it. When I give it gas the boost gauge will go down and the car idles perfect for about 2 or 3 seconds then the boost gauge jumps back up halfway and it starts idling terrible again.
 
Very likely you blew off an intercooler pipe. Look around

I had a moment here at work, so I went out and looked and all the intercooler pipes are good. I cranked it up and everything is idling fine now. Factory boost gauge goes down to normal instead of stuck over halfway and when I give it gas it revs up normal then idles back good
 
The factory boost gauge is based on the MAF output as massaged by the ECU, so It's an indication of what the ECU thinks the airflow is relative to the RPM and throttle position.
Any one of those sensors acting up could cause something like this but I'd start with the MAF and it's wiring after making sure all the intake piping and vacuum lines are connected. Start with the easy stuff first.
 
well I crunk it up to come home for lunch and it idles fine but when I went to take off it started sputtering really bad and the boost gauge jumped up and it started smoking out the tail pipe
As I said. You probably blew off an intercooler pipe. It will idle fine like this sometimes but the minute you give it gas most of the air isn't making it to the motor. ECU doesn't know that and is fueling as it should. End result way more fuel in the cylinder, black smoke and car does not run.well if at all.
 
I had a moment here at work, so I went out and looked and all the intercooler pipes are good. I cranked it up and everything is idling fine now. Factory boost gauge goes down to normal instead of stuck over halfway and when I give it gas it revs up normal then idles back good
Pipes are good....how did you check? VIsual only? If so that won't cut it. Grab then and pull.
 
Pipes are good....how did you check? VIsual only? If so that won't cut it. Grab then and pull.

Found it, right side where the pipe connects to the intercooler blew off. I get off work in about 30 minutes, so going to hook it back up and hope like hell thats all it was
 
Man you DSM wisemen are freaking incredible. The issue was fully diagnosed....without seeing or hearing the car in person, or by video...you recommended the proper procedure to resolve the issue....spot on....and it was fully resolved in a matter of minutes, slam dunk! That's a testament to the knowledge, the understanding, and the care that is expressed here on a daily basis. DSMTUNERS ROCKS! Without this forum, even though I have a Factory Service Manual, I would have been clueless in my GST restoration with some of the issues I experienced. Kudos to all of you.
 
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