Black88Z

The car was giving me symptoms of a bad coil, it would usually run ok but would occasionally lose all its power, sometimes at a stop the rpms would start climbing, and i would really have to hold the brake down to keep the car still (never got bad enough i had to put it in neutral or shut it off). It would even stall out sometimes, then when i go to restart it it starts fine and acts like theres no problem. For a while it never would throw a code, then it finally did. Gave me 42 and 51.


Code 42: Fault at electronic spark timing circuit OR Fault at direct ignition system OR Fault at fuel cutoff relay circuit

Code 51: PROM error


The other day it stalled on me 3 times, 2ce within about 3-5 miles. Each time after it stalled, it didnt want to restart immediatly, but after a few minutes it would, and it ran ok again. I replaced the coil with an msd coil and it seemed to help for a little while, but it stalled again. I ran the codes, 42 and 51.

Replaced the ESC because i read thats a common cause of 42, hasnt stalled (yet, knock on wood!!) but just gave me the ses light (42 & 51). Shut it off, restarted it, and still had the light. I shut it off again, came back about 15min later and started it, no light and no problems.

I have noticed that almost every time (to be honest, im almost positive its been EVERY TIME) i get a code, 51 pops up with it.

I have ohmed my injectors several times, warm and cold, and they all were within spec. I havent done it in about a month though, so i will do this AGAIN, just to be sure.


Im not very familiar with PROMS, i know their function but dont know much about them. If its giving me 51, what can that mean?

Thanks for the help

Black88Z

Anyone?

Black88Z

Black88Z

Theres really no one with any suggestions here? Still having the problem and would appreciate the advice..

camarosrock1989

iTrader: (1)

According to the service manual, 51 is accident detected. History code diagnosis. I have the book right in front of me. I am still trying to learn how to read this huge book. I can scan the whole page for you tomorrow if you like and post it. Tells a lot more about it. How to clear and what it all means.

Tuned Performance

iTrader: (92)

With seeing the code 51 you may have a memcal issue or a ecm failure. The 1227165 ecm while running you can tap on the ecm this my flex the circuit board to duplicate the condition. I havent seen too many memcals fail over the years but did have one a while back have a bit flip causing the code 51.