need help with surging engine.

[firefighter]

I have a 97 prix with 3.8L auto. I start the car and it sounds like it is sucking alot of air, as if the filter isnt there. The engine surges and wants to die but soon as I give it a little gas, its fine. Then if I get off the gas it will die, sometimes! Then when I drive down the road it runs fine unless I let it coast and it surges from 1500rpm to 2000rpm!!! I have thought about possible plugs and wires, as if it is a miss. I am thinking now possibly a MAP sensor, MAF sensor, or a TPS sensor!! Any help would help!! Thanks

[Lawngoose]

Do you have and Check Engine Lights on? If so, get them scanned and either let us know what they are or look them up. My car did similar things when I had a vac leak...but getting your car scanned is your first step.

Did this start occurring after any work/maintenance?

[FoSHO99]

Sounds like a big Vac leak. That would be your sucking sound... Get some starting fluid and spray it around parts of the engine and you should be able to tell where its coming from when the idle changes.

[firefighter]

Thanks, I will try and trace it down, and check into getting it scanned. I appreciate it guys.

[98SEGT]

Vac leak, find it with a can of carb cleaner.

[firefighter]

Ok, I found a vaccum leak. Fixed it, went and got it scanned. It had 2 codes, MAF sensor and TPS sensor. Car still does it, and the sucking sound is coming in the air intake like it is starving for air. It has a new air filter and the airway is clear. So I am thinking MAF sensor because it is starving for air. I tried unplugging it and it doesnt change the way it runs. So now what? I dont want to just start replacing every part. Thanks

[Sabrewings]

The sucking sound is caused by the surging, not the other way around. That's normal when an engine is trying to rev.

You probably have issues with your FPR, TPS, or IAC.

[firefighter]

Well its sucking air to try and stay running. If I dont give rev it up a little, it will die on me!! And I mean rev it only up to around 1500rpm, so not alot, but just enought to keep it running. Then if I drive it for about 20 mins, it seems to be ok for awhile.

[Sabrewings]

Well its sucking air to try and stay running.

Exactly. But that's not the problem, only a symptom. If you have a codes for the MAF and TPS, then replace those. Then if it doesn't go away see about cleaning or replacing your IAC, and finally your FPR if nothing else has done it.

[firefighter]

Right I understand that and agree with you, I wasnt trying to say something different! I guess I just have to start replacing sensors untill I get one right!! LOL, thanks