Installed the Walbro fuel pump and I'm still having the same problems. Relays are good, no blown fuses. I'm running a full tank of gas and still leans out under WOT. Any other ideas on why?

 

I would have to say the tune.

 

Are you sure it's leaning out? May be a bad WB sensor? What AFRs are you seeing and what software are you using to log?

 

Clogged Injectors that are limited in flow now? Maybe you can get ahold of some stock injectors for cheap from someone that upgraded already. Did you wire a dedicated power line from the battery that gets activated with the regular fuel pump power via a 30 amp relay?

 

Oh I'm sure. I was leaning out before I got the gauges. I took it to 2 different shops and their AFR's were showing lean. My AEM wb is brand new so I'd hope it wasn't bad. Right now I'm just running the Cobb stg 2 93 Oct Customed from MACH V.

 

I'll look into the injectors. Let me try the power line from the battery out.

 

Can you elaborate on this? I would like to know what you mean.

 

If you think it may be injectors, check your spark plugs. It's rare for all injectors go bad/clogged at the same time so check you plugs and see if one is discolored compared to others. If one plug is more white compared to others, that may be the injector that is bad.

 

This is what I'm going to try and do.

 

have you reflashed back to stock to see what happens?

 

It leans out even worse when I take the Cobb AP off.

 

Checked the spark plugs and everything looks fine. No lean indications found on the plugs, here's some pics.

 

Sorry, I should've been a little more specific. You actually need to do this right after a few WOT runs. Checking them after long periods of cruising or idle wont tell you much since it only leans out under WOT.

If this picture is actually after a few WOT runs, then I would say your plugs look fine and doesn't show any signs of leaning out.

 

Oh ya I made sure I ran it WOT before I pulled them. I guess I will keep searching thru to see if anything else is causing it.

 

Did you end up setting up a dedicated wire to the fuel pump from the battery yet? I'm running into this issue and I think we are going to try this tonight on my car to see if it's the problem.