Slight Rough Idle & Acceleration Hesistation

[skyvette427]

97Q... Problem started yesterday so still trying to narrow down exactly when it happens.

It seems to only be when warming up... not fully cold and not fully warm...

Not ruling out a bad coil but I've had bad coils and this feels different... the main different thing is the throttle cutting out for a slight second when accelerating.

MAF Sensor was replace about 3/4 years ago as well as idle air temp sensor.

When it idles rough its more of a RPM drop to about 450rpm and at time will ALMOST stall. If i give it gas in neutral it runs just fine...

Power is still there when it works fine.

I was told maybe clean throttle body or a fuel injector but the issue is so random and sporadic at this point I can't really pinpoint.

No new codes besides 1 bad knock sensor since I bought it and also ignition coil code since I replaced them all with cheap eBay ones (im paying for those coils as they slowly die and replace with good ones)

Any ideas?

[Q451990]

How confident do you feel about that MAF? That would still be my starting point.

[skyvette427]

How confident do you feel about that MAF? That would still be my starting point.

Good point. I have had A bad MAF and the issues seem different unless this one is starting to bad but isn't fully bad?? Wouldn't it throw a code though?

Update today...

I listened to the engine running with the hood open and noticed a slight air leak from the intake/throttle body connection. Went ahead and readjusted and tightened the connection and don't hear the air leak anymore. Car behaved perfectly fine heading home...

It seems so silly that I'm still not believing that was the issue.

[Q451990]

Depends on how bad the leak was - if you had enough air going in to the engine that wasn't metered by the ECU, it doesn't seem totally out of the realm of possibility that it could "confuse" the ECU enough to throw things off. Especially if it's already running in a sort of safe mode because of the knock sensor code... The ECU goes to the least aggressive timing advance map that it has (as if it's detecting spark knock) when it knows that the sensor(s) aren't working and it can't "hear."

[skyvette427]

Problem is still here.

It is very random and from what I'm reading it could be the o2 sensor starting to go bad. Any experiences with this?

I also read there's 4. Any way to test those? I also read they won't throw a code sometimes.

Any help is appreciated.

[skyvette427]

One week since I cleaned the throttle body and the car is running great!