1997 Grand Am GT (3.1 Engine). Intermittant throttle surging problem at idle speed.?

Question:
Does not happen all the time and seems to happen after vehicle is warmed up. Vehicle starts well, good fast idle until warmed up, and surging issue does not seem to start until after being driven for a while. On last outing, started and stopped at 4 in-town locations - everything O.K. until started at the 4th place and engine started "surging" at idle speed. If you give it a little gas up to approx 1500-2000 rpm (In park) and let completely off accelerator, it will return to NORMAL IDLE for about 6-10 seconds and then idle will drop (almost like flipping a "slow down" switch) and surging will start. Repeat cycle by increasing throttle ... so on and so forth and the same cycle will repeat itself. Any help would be greatly appreciated - I have to do the work myself if at all possible due to finances ...

Answers:

Can you use a dual plane intake for mpfi or do you have to use a singleplane?

Hey, I am going to assume since you are planning on doing this yourself that you know some about auto repairs. A surge at idle speed could be caused by a number of things. I would have to take it to a garage but here are some of the things that will need to be checked:
PCM and MIL (Service Engine Soon) are operating correctly.
Check the PCM grounds to make sure they are clean and tight.
Check the vacuum hoses air intake and the ducts. . make sure nothing is clogged or restricted.
Check the air leaks at the throttle body mounting area, MAF sensor and the intake manifold sealing surfaces.
Check the ignition wiring for crimps or cuts, etc. . .
Check all wiring.
Make sure the O2 sensor is responding quickly to different throttle positions. . .because it should.
Check to make sure the EGR valve is not stuck open.
Check the fuel system.
Ignition System, spark plugs and wires.
And, finally if it is none of that I would check the exhaust system.

Car window (power)?


Good luck if you tackle this on your own.

Car won't start and if it does then cuts off minutes later.?

Check fuel filter and fuel pump

2004 6.0 ps diesel overheated and lost power?

Well, your car is acting a little odd, but I'd still look around the engine compartment for split or broken vacuum hoses. There are a bunch, trac all you find to both ends, it may help...otherwise, it may have to do with the "minimum idle" adjustment, or MAF/IAC...the maf sensor can get dirty and give false signals to the computer, and the iac valve may be dirty as well.
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