Stumble off idle - runs fine all other RPM

[Silber]

Little bit of follow up, thanks for the tip on the vacuum leak, did some research and it turns out you can check for a vacuum leak with Durametric by looking at MAF values.

At idle MAF should be 10 to 15. If you have a vacuum leak it will be lower. My MAF value is actually higher, 25 to 27 at idle spiking to 90 if any throttle movement.

So, it looks like the MAF sensor actually is bad. A vacuum leak would’ve showed a lower number.

MAF arrives tomorrow, we’ll see if that fixes it.

Silber

[blue62]

Originally Posted by Silber

Little bit of follow up, thanks for the tip on the vacuum leak, did some research and it turns out you can check for a vacuum leak with Durametric by looking at MAF values.

At idle MAF should be 10 to 15. If you have a vacuum leak it will be lower. My MAF value is actually higher, 25 to 27 at idle spiking to 90 if any throttle movement.

So, it looks like the MAF sensor actually is bad. A vacuum leak would’ve showed a lower number.

MAF arrives tomorrow, we’ll see if that fixes it.

Silber

A low MAF reading can come from a number of things. Yes low MAF readings may point to a vacuum leak but that is a very general indicator. Also a proper vacuum test can show you many other things besides a vacuum leak. such as early or late valve timing early or late ignition timing. poor compression. poor valve seating.( Valve leak by). muffler or CAT restriction.