My car is a 1994 LT1 that I have modified, but I haven't yet touched any internal engine parts. My problem is that my LT1 is basically not getting fuel. It starts and normally idles ok but any response from the gas pedal and it acts like it is out of gas. However this is the part that has me confused. I just installed a brand new racetronix fuel kit because I knew I had low fuel psi at the fuel rail so I thought that was the problem. I also just installed a new FAST adjustable fuel pressure regulator. Now going done the street when it starts to stumble and die at times my O2 millivolts on my LT1 scanmaster show that it is burning Extremely lean, so I know the engine is barely getting any gas at all. I also have put a fuel pressure tester on the rail and drove it while this is happening and to my surprise I am getting a normal 42 psi once pressurized, and 33 psi while running down the road. Even when the car is stumbling and dieing. I don’t think that all of my injectors would be bad so I ruled that out. My only other guess is that my computer is not telling them to fire...but just four months ago I just got my computer reprogrammed at PCM4Less so I am not so sure if that is the problem. I also was able to get a code 44 when the car was dieing on the way home from testing it. If anybody has any ideas on what I should check next or what it might be I would appreciate the advice.

Thanks Zack

 

Ok, I have the same engine and year. If your car is hesitating or feels like it is stumbling (i.e. jerking and loosing power) then you may have a bad distributor. These distributors are known to go bad and are expensive and a pain to replace. It is located at the bottom of the front engine, partially covered by the harmonic pulley below and water pump above, and yes both must be removed. A good mechanic will charge 3-4 hours to do the job or you do it. The water pump comes off easy from above and the pulley (hopefully not the balancer) comes off next. The distributor is bolted on and comes off without the shaft which is keyed. The distributor is $675 via the dealership or Summit ($389.95) or Gyrhead.com ($384.36/$65.92). The part number is 10457702 via GM Performance Part. The ignition module is D1986A. Do not just replace the cap, if the distributor is bad, it will take out the cap but you will not know this unless you replace the cap and hope it works a week later. Some mechanic write-up say replace the ignition module due to some instances of the distributor hitting the ignition module which then re-hit the replaced distributor, but the one GM mechanic said he never had to this. The module is next to the coil which is above plug one and easy to get to. I am replacing both since the distributor is a one shot deal and the module is $66. You will need to have the distributor check out by a mechanic for dropping a cylinder (their term)(a short between two plug wires) or use a volt meter with a high voltage DC probe and see which cylinder is not getting spark when you gas the engine. IF YOU WORK ON THIS CAR, USE JACK STANDS AND BLOCK THE WHEELS FROM MOVING, AND LEAVE THE JACK AS A BACKUP ONLY. THIS CAR FLEXS AND WILL CRUSH YOU WHEN IT GOES DOWN. USE A LOT OF SUPPORT, THE MORE THE MERREIER BEFORE YOU PUT YOUR BODY UNDERNEITH IT.

 

Thanks for all the info...but. I just recently put a brand new $700 Dollar Dyna Spark Distributor on my Car along with MSD Super Conductor Wires, an Accel Coil and Accel's 300+ Street and Strip Race Ignition, so my ignition is taken care of in all areas. Also I think that if it was indeed an ignition problem and not a fuel problem...why would my scanmaster have my O2 millivolt in the 100's at times and my ECU throwing a left bank O2 sensor lean condition Fault Code? I would think a fuel problem would be the most common thing. I also in hopes of fixing my problem, put a FAST Adjustable Fuel Pressure Regulator onmy rail and at idle with 34 psi of fuel pressure the thing still is choking if I touch the gas. I also noticed though, if I pull the vaccum hose off the regulator to simulate WOT my fuel pressure stays the same..So I know that is a problem. Just wish I could get things sqaured away on my Z, I haven't even got to try out my new dual electric exhaust cutouts that I just put on it before it took a ****.

Zack

 

bump....Anyone got any ideas???