I have a weird lean condition on my 1991 supercharged TA.

Thought it might have been an intake runner leak as I just removed and replaced them for the new AFPR, but I sprayed carb cleaner on the tie-in points and get no increase in engine speed.

I didn't have this problem prior to this though??


I really don't think I have a vacuum leak but how can I be sure?


I have the AFPR set all the way high and am at 16:1 at idle !!!! My fuel pressure is at 42 psi w/ vacuum on. Can it be a bad fuel pump??? Can I have high pressure, but low volume???? I am running a new Walbro intank and an ATI inline.

I am going to bypass the inline to see if it makes a difference.

The filter is new, but I am going to change it too. Seems to me that you can still have high pressure through a clogged filter, but not enough flow.

Thanks.

 

Is car going into closed loop?
What do your BLM's say at idle? Are you using a WideBand A/F METER or just a regular O2 meter? Do you have a header leak causing false reading?
In a speed density car a vacuum leak will cause a rich condition not lean as other cars would.

 

I'm just looking for an answer. Does it really matter if the car is lean at an idle? There is no boost and not much,if any, load on the car. The only thing I can think of that would be a problem is maybe cylinder temperature being too high? Just a thought. Please let me know what you think.