1992 Paseo - Unsteady Idle

[wadeblues]

I just bought this Paseo. The idle fluctuates when cold between 1200-2000 rpms. Once the car is warm, it seems to quiet down, but still idles between 1000 - 1200 rpms. It will also lurch when at a stoplight - more pronounced when the a/c is on, but still when not on.

When cold, the idle sounds like it is gasping for air. It is a regular pattern (up, down, up, down, up, down).

There is a (fakey) K+N air filter and enlarged exhaust, but I don't know if any other engine modifications were done. It is not a cold air intake, just a larger tube basically. Could this be causing the problem, the air intake or the exhaust, or both? If not, I have read maybe the Battery connections, fuel filter, air intake leak, or vacuum problem. No problem on the first two, but I don't know how to check the latter two problems.

Oh, also the brakes seem to be not grabbing well, and they were just serviced. Does this indicate a vacuum problem on this car?

Can anyone help? Thanks, Wade

[riko666]

check the air-temp sensor, whoever put on the new filter may have fit the sensor incorrectly or not at all...if its not that, check spark plugs / spark plug wires

[Paseo2nr]

check the throttle wire, body, and intake manifold. there could be a crack or leak in the last two.

[aqcy]

i have a similar problem too...

when the engine starts cold... idle speed is around 550 - 600 rpm... and yes, the engine feels like its gonna stall and grasping for air...

but after travelling, and when the engine is warmed up, the idle speed would go back to normal around 750 - 800 rpm...

is this normal or is there something wrong?

Also, is the air intake pipe to the throttle body a 2.5 inch inlet? or 3 inch?

[wadeblues]

Thanks Rico and Paseo2nr for your responses. I have something to add. The speedometer m.p.h./k.p.h. is pulled up with an increase in r.p.m., even when the car is parked. Does this indicate further a vacuum problem, or something else?