Chevrolet Repair: Silverado computer, fuel pressure regulator, engine cranks

Question
QUESTION: Robert,
First off, let me thank you for your time in volunteering to share your knowledge. I have a 1993 Silveraado, ext cab, 6' bed, 5.7L, tbi, 160,000 mi., 2wd, a/t, p/s, p/b,p/w, pdl.
The engine cranks, there is fire at the plugs, but no fuel from injectors. Fuel pump on, but no "clicking" at injectors. 12v at injectors, and at ecm terminal for inj a and b. I am told the computer is bad. My problem is, the computer is an aftermarket, and whoever replaced it did not record original info from oem computer. Is there a means of identifying a correct computer to replace with?? I believe the previous owner, or whoever replaced the prom, did so with an aftermarket prom, as the one in this computer is marked "superchip". I would be happy just to get the factory one and bring life back to an otherwise carburetor destined engine. I aquired this truck after the owner abandoned for not being able to get it running. He replaced plugs, rotor, cap, ign module, distributor, fuel pressure regulator, and maybe the computer too, since it was dislodged from the glove box, but connected when I got it.
Any assistance you can offer would be greatly appreciated.

ANSWER: Hi Claude... the dealer should be able to give you the info you need for the computer from the VIN# a quick try would be to find a truck with the same engine and options and try the computer from it....also if you had a scan tool you could try putting truck in limp home mode/ field srevice mode and see if it will run....hope this helps

---------- FOLLOW-UP ----------

QUESTION: Robert,
Thank you. I went to dealership to buy computer, only to find out that this "aftermarket" computer also had an "aftermarket" superchip installed between the prom and the computer. Removal of the superchip solved the problem, and I didn't have to buy a computer.
Question...what type of scan tool enables you to place engine in field service mode?
Is it generic to all make/model vehicles, or specific?
What types of errors will it overide to enable a vehicle to be driven to shop or home?

Again, I appreciate your time and knowledge.

Claude

Answer
Hi Claude.... any OBD2 scan tool should be able to activate limp home mode...what it does is set default values for all computer related functions to allow the truck to limp home. it will not work say if computer is toast but will if it is a sensor related problem....glad to see that you got your problem solved....Bob