jackpawt883

okay so i was hammering on the car, after not driving it while it was down for a new trans and converter, and it cut off at around 5,500 rpm and after it cut it made the biggest backfire, so bad people actually came to where i was to see if i had gotten shot. i work at a dealer and a couple of my older coworkers think the motor jumped time, anyone else had something similar happen?

grabbem88

Mine did that a few times and actually made other drivers pull over thinking I shot at them..

A few months later my opti finally crapped out on me..

shoebox

Sounds like sudden opti rotor failure.

jackpawt883

so do i need a new opti or am i pulling the front cover to get to something chain driven? and thanks for getting back to me so quick!
also now the car sounds like its firing on one cylinder, seriously the starter cranking it is faster than the engine run speed

Injuneer

Pull the distributor cap and check the rotor. They can shatter, or the screws can fall out. Problem is the water pump has to come off, and the damper/pulley has to be removed from the hub.

jackpawt883

thanks man, i'll probably pull it all apart on tuesday. any tips for a first time opti pull? or is it just pretty straightforward pull the water pump & damper
also any opinions on keeping the car down until i can get a cam kit? or maybe a 24x swap kit with timing cover?

shoebox

If the engine cranking speed is indeed noticeably faster than normal, you may have lost the timing chain (kinda rare). Pull a valve cover and look for valvetrain movement while cranking. If that is the case, there may be even more damage from valve clash with pistons. Bent pushrods would be the first indication. Hopefully, it is just the rotor, though. That is more common.

Cam swap and 24x? That sounds a bit ambitious for you judging by things you have said so far.

jackpawt883

actually ive rebuilt motors before, swapped transmissions by myself on jackstands in this car and on my 96 dodge truck, and i thought these werent interference motors? and no i mean the motor will run but it sounds as though it's managing maybe one cylinder, thats after a couple startups since the huge backfire (which it actually ran fine for two ignition cycles, enough to where i raced my buddies z28 and kept right next to him the whole pull) which kinda makes me think its not the chain, that maybe it detonated the rotor

Fatdog2

Sounds like when my map sensor died on my 93 bird.I dunno if a 95 has one though.My02.

jackpawt883

so i got working on it today and i pulled the plugs on the driver side (because im doing long tubes while its down, decided against the 24x conversion and cam due to lack of funds) and they were all soaking wet like that whole bank wasnt firing, which makes me think its what shoebox said about the rotor failing, and i turned the engine over by hand and it felt like it did when i had to turn it to change my trans about a month ago so my compression is good, just battling these ******* manifold bolts

Injuneer

All years of the LT1 have a MAP sensor, but only the 93 uses it full time in the speed-density A/F ratio control system. Lose MAP or lose IAT and the speed-density system goes into limp. 94 and up use an MAF sensor as the primary input to the A/F ratio control system. Loss of MAP will cause issues with the spark timing tables and long term fuel correction memory cells, but not as likely to shut things down. If the MAF sensor fails, the 94 and up models default to speed-density.

jackpawt883

sorry to dig up a kinda old post, but shoebox was right
took the opti off and it sounded like a salsa shaker
cant wait to get my baby together so i can finally fix my truck (96 ram)

shoebox

You shouldn't be sorry for posting back what you found. It helps anyone else that does a search.

jackpawt883

true! i got it running at about 1 this morning but my headers were hitting some lines and im out of zip ties
but tomorrow is always a new day