Thread: Why am I all the sudden running lean?

Why? Better to pressure test the system. You'd be surprised where you might find leaks.

C

All good suggestions, Im setup for blow thru with all brand new couplers/t-bolts so I didnt think a boost leak would even be noticed.. Wouldnt this cause a RICH not lean condition?



Anythings possible though so ill test that as well, Will have to look into whats needed to pressure test. Also gonna rip out my stock cat which was making noises and put on the test pipe.

Hey Ben,

Fuel pressure is listed at tad under 40psi on the gauge, When I pinch the line it does not change 1 bit.......

Im reading I should be at 36psi car running and 43psi when I pinch the line, Running its around 36-38 when I pinch the line NOTHING changes.

Pull the line, and make sure it has vacuum.

C

why not just retune the car for the "new" maf?

I had a bad ground once and it caused a similar lean condition

I swapped an N62 for an N62 I have a tunable ECU but no dyno local.
I also have a JWT ecu that I can probaly get re-tuned from JWT and test with that. Im starting to lean torwards
a tune issue more than a physical problem. The car was just parked for 3 months or so and replaced the maf thats it.
All hoses etc are all new when i did the swap i replaced every vacuum hose etc.



Pulled the line and had vacuum and gauge actually changed. So were good there.

So you're saying your pinch game is weak? :P

C

HAHHHAA Chris you literally had me laughing at my desk. Pinch game is in-deed weak, Gonna look this thing over top to bottom this weekend
and If i still come up short gonna send out my JWT ecu that's in storage to get programmed for my setup and just see if it behaves any different.

Good on 'ya Daryl.

I know I asked before, but have you done a pressure test on the entire intake tract? I'm a BIG believer in that, and you'd be surprised at the places you might find a leak.

C