Fuel Pressure and MAL 45 code

[mhelli1975]

I took the gn for a ride the other day and noticed o2 #'s in the high 800's and low 900's. I also have been getting the MAL 45 on the scanmaster. I stopped the car, popped the hood and attempted to lower the fuel pressure. I attached the gauge to the rail and no matter what i did, i couldn't lower the fuel pressure. the reading at the rail was around 30 lbs and then it would slowly drop to 25 lbs then 20, 15 and the car would stall. Bought a new accufab fuel pressure reg. and installed it yesterday. Took the car for a ride and the same thing is happening. anybody have any similar issues. thanks in advance for any help.

The part that I don't understand is the low fuel pressure with the rich condition, I thought that you get a rich condition when the pressure is too high, not too low.

87 gn - 4.1 production block, PTA-52 turbo, Stretched intercooler, MSD 50lb injectors, Red's Fuel Pump, Accufab Fuel Pressure Reg., chip that came with the inectors (don't know much about it).

 

[Joe 1320]

Check the BLMs and INT, this will tell you what the computer is actually doing or seeing that results in a rich condition. Ideally you want 128 on both.

Some things that can cause a rich condition:
bad 02 sensor
false lean from a leaking exhaust prior to the 02 sensor
Stuck injector
pinched return line causes a spike in fuel pressure
bad ecm

the list goes on from there.

This page may help:

http://www.gnttype.org/techarea/faq/BLMINT.html