stumprrp

iTrader: (2)

Hey guys,

Im posting this for my friend with a freshly build 383 in a 1994 corvette, hes having some serious issues actually getting the car to start, it just cranks and cranks and MAYBE pops once or twice but doesnt start.

Let me try to make a very long story short.

After the motor was built the car initially ran like crap, however it seemed to run better after some miles and he put about 80 on it, during the middle of a tune they were uploading (street tune, started it with PCM for less) the car shut off and threw an SYS light (only on corvettes). Needless to say he replaced the PCM with another one and sent it to PCM for less.

Once the new PCM was installed the car once again ran like ****, the plugs and wires were good, tune was good, everything seemed ok, the battery however was no good and the car wouldnt hold a charge so he replaced that.

After that, the car has not started since. There is spark from testing the plugs on the frame, there is fuel (plugs are getting SOAKED), 40 PSI from the regulator, the tune once again is fine (quik95lt1 looked at it), there is proper voltage from the opti spark so we are assuming that is fine, the coil is brand new.

PHEW, there is more testing that was done but needless to say the kid is losing his mind and the car wont start.

Any input anyone?

Thanks alot.

old93camaro

iTrader: (8)

have you checked all three grounds???

stumprrp

iTrader: (2)

i personally havent checked anything im just there with him during the process lol but im pretty positive he checked all the ground, along with every connection that could be checked with a multi meter.

c4ls7

^^^to the top^^^

fex77k

iTrader: (2)

How does the opti look? I had mine blow up on the dyno after only 300 miles, both the rotor screws had come out.

stumprrp

iTrader: (2)

if he is getting voltage to the ICM wouldnt that mean the opti is fine?

also has an H62 code, which i believe is an oil temp sensor and tach error.

fex77k

iTrader: (2)

Well its the high voltage side of the opti that might not be alright, yea the coil might fire but if the rotor isn't turning then it doesn't matter how good the coil is. Its only a suggestion and it wouldn't cost you anything but a couple of water pump gaskets to check it. Its been the same thing both times it happened to me.
Here is my MSD opti that I've blow two rotors out of.

I didn't realize that there isn't any loctite from the factory on the rotors so I destroyed a new rotor after only 300 miles.

Since the MSD were hard to get, I guess they were on back order for a bit, I had to slap a stock rotor on there till I got a new rotor in. The rotor lasted longer than it should have, 50K miles on the AC Delco and 10K on the MSD(cold weather made it brittle and it blew up).

stumprrp

iTrader: (2)

damn optis, ill let him know, hes looking into the H62 code right now i guess that can cause a no start as well

quik95lt1

iTrader: (7)

rob h62??? I cant find it r u sure thats the number?

quik95lt1

iTrader: (7)

justin call me i didn't know you were throwing the h62 code........its got nothing to do with the opti/ign/fuel sys......its a tach signal issue to the ecm.....i guarantee this is it

heres your issue its somwhere on the ckt121 white wire between the coil and the dash/ecm......maybe the tach filter or the ground to the tach filter......a short to ground on the white ckt121 wire will cause the no start/poor run condition on the vettes due to a bad tach signal to the ecm.......