944 turbo LOSES FUEL WHEN BOOSTING! HELP

[240Timmons]

Greetings fellow 944 fans! I'm new to the forums and very frustrated with my 951, as I’m sure we all have been!

I've been poking around on the forum and I haven't found my specific issue fully addressed but I’m sure it's been discussed many a time, so if this is a redundant repost, please kindly point me in the right direction I hope this is a common problem and i'm over looking an easy fix!


My Issue:
Car goes completely lean after a few seconds of boosting (kicks, pops and loses power)


Back Ground Story:
I purchased my 86 951 a few months back. When I test drove it, it would only boost to about 9 psi and ran at the correct AFR's, but it didn't have too much power. After taking it home I discovered 3 large boost leaks (hole in the cold intercooler pipe and two rubber boots were torn)... After I fixed the boost leak the car would (and still does) after a few seconds of boosting, it run lean enough to not support combustion. Even when I run it at the same 9psi or lower it acts like it runs out of fuel.
The fuel pressure feels EXACTLY like it's running on an accumulator and after a bit, it runs out of umph until you take it easy for a few seconds (10 or so) fuel pressure seem to "recharge". The car seems to run better and not run lean as quickly once it's up to operating temps.

The car idles and cruses smooth and at the correct AFR's (maybe a little lean) but anything over 0 manifold pressure it will lean out after a few seconds. Keep in mind, the car will run at the correct AFR’s even if I’m at 6000rpm but not in boost. The car is also very very sluggish when cold with horrible throttle response.


Here's What I've Done So Far:
I've drained the fuel, installed new fuel screen, new fuel pump, new fuel filter, new fuel filter, and new stock fuel pressure regulator, pulled all 4 injectors and cleaned them. Rebuilt the waste gate and shimmed it (boosts to about 14 psi now). I've tested and cleaned the Mass air meter and it tested perfectly, both temp sensor and the door. Changed DME/Fuel pump relay. Tested all of the temp sensors and found that the one with two open prongs had and “open” so I used a variable resistance box and simulated a properly working temp sensor, still no difference in performance. I used a smoke machine to look for boost/vac leaks, there were none. I’ve checked all fuses. New cap, rotor, wires and coil. Pulled the DME and the KLR and inspected it for damage inside and out. The pressure tube going to the computer is not kinked.

My only two ideas of what could be wrong:
Fuel pump not getting enough voltage
KLR or DME is faulty

Honestly at this point I’m getting very discouraged and I am running out of ideas of what it might be. Anything can only help at this point!

I’ll edit my post if I remember anything else that I’ve done

Thanks in advance for any advice!

[240Timmons]

admins, this was a repost on accident. please kindly remove this thread. Cheers