hey guys.. i never had a problem with low end.. even after some mods. but after i had the opti replaced i started having the hesitation at low end problem that so many people on the forum have. but now im wondering if it could be age. cause my '93 LT1 motor blew the other day. i heard a loud backfire.. and then i couldn't restart the engine. i hope you guys could help me figure out a couple things..

1. the low end hesitation.. i changed wires, plugs, fuel filter. and the fuel presure is good. could it be some electrical wiring that's old or the opti again? what about timing?

2. and if my engine acctualy blew or not. cause i'm not sure.

thanks!!!

 

A bad Opti will throw a DTC 16, scan the computer and make sure. It did on my 93/

 

anyone else? should i do a rebuild?

 

i think you need to figure out what wrong first. check the oil does it have coolant in it? metal shavings? did it spit antifreeze anywhere. i've seen an opti go out and the car will backfire, die , and not restart.

 

2. I doubt the motor is blown. When it backfired, how were you driving the car? ie: rpm, speed, throttle on the floor?, etc. Did it shoot any smoke when it backfired?

1. I would put money on a bad opti or bad installation. If you had it done very recently they should fix it for you. If you did it yourself, have fun doing it again. I had the problem and after my opti replacement it was still kind of around. Eventually determined it was the EGR valve, but i don't believe you have one on the '93, which leads me to believe it's the opti again. You've done all the right things, fuel filter, plugs, plug wires. Did the computer throw any codes before it died?

 

I would check to see if I had spark before I decided to rebuild the engine. That is big conclusion to jump to. You might just have a bad coil, coil wire, ICM or opti.

 

it was in the morning. i was just warming it up. it was hesitating bad and it went 'bang'. i didn't see smoke though.

 

Possibly they put the spark plug wires on incorrectly causing misfires.