Something happened while driving the other day. The motor started running real bad. I reset the ECM and thought it was better. I was wrong. I went for a dyno run yesterday and it was running so lean that they did'nt want to run it. I tried increasing the fuel pressure and that did'nt help much. The cat was glowing red and ready to have a melt down. I somehow got the car home and scanned it. BLM's were pegged at 160. Tried a different ECM and a different prom. No good.
What happend????
O2 when bad? (Its almost new). Clogged cat? Clogged fuel rail?
I checked my FP and it was good (46lbs.).
If anyone has any suggestions as to what went wrong I could use your help. Thanks

 

Possible vacuum leak. Check your intial timing, and make sure all sensors are plugged in tight and you see/hear no visible leaks.

 

I would think a vaccum leak would cause the engine to be overly rich...trying to compensate for the additional 02 introduced into the motor.

I would check the 02's voltage, it might possibly be faulty....especially if it's a Bosch. I would check fuel pressure again....while driving and see if your pump is getting weak. Did you check it with and without the vacuum hooked up to the press. reg??

 

Last night I removed the cat and gutted it. It looked ok.
It was rianing so I was not able to drive it. Ran in my garage.
For some reason the BLM's were stuck at 128 in closed loop.
My AF guage was showing lean. The injector Volts were 450-650mV. The FP was checked with the vacuum removed.
The pump is almost new-stock Delco. The O2 is also almost new and it's a stock Delco.
Any thoughts? Other things to check? I did'nt notice any vacuum leaks but I did'nt look real good. Nothing obvious.
Thanks for your help.