ok so i go to an automotive tech school, and i was doin one of those run-rite fuel system cleaners. i was sprayin some throttle body cleaner in my TB when it was runnin and i had to keep givin it some gas to keep it runnin or else it would die cuz it was blowin out all sorts of dirt out my exhaust. so this kid that was in my class for some reason decided to shut it off in the middle of this. when i started it back up, it barely ran then died. but when i turned the key off, it was still runnin cuz of all the cleaner in my intake manifold. but the weird thing was that i think it was runnin backwards cuz it was shootin all sorts of black smoke and **** out my throttle body! it did this for like 5 seconds or less, then made a real LOUD bang noise, then shut off. is this bad for the motor, or cause excessive wear on valves and/or head??

i started it up a couple of min after this and it was runnin alittle sluggish for like an hour or so, then was fine...

im doin a compression test and 5 gas emssion analyzer tomorrow to see how its runnin, ill let u guys know.

 

It may have been. In the older days, especially with v-8's, we called this "Dieseling" Where the engine did in fact run backwords and blow through the carb. Don't ask me why, but it would happen when the timming was off and/or was idleing too fast. It was actually called pre-ignition, if I remember correctly. I don't know if it can hurt your engine.

 

i did a comp test, and it showed 170psi on all 4 cylinders, and it seems to be runnin fine now. now that i think about it, i dont think it ran backwards, it was just igniting off the carbon and TB cleaner in the manifold. thanks though

 

Good to hear that the car is fine. Now all you need to do is kick that guys *** lol

-Matt

 

Don't ya just love it when the motors backfire out of the intake? Makes me wanna **** in my pants everytime it happens, always wondering if you get to pull the motor to replace it next.

 

When my little Mazda b2600 overheated real bad it did that, then warped the head and whatnot. Glad to hear the car runs good though.
Oh, and i had a buick regal with the v6 in it once. one day i tried to start it and it backfired through the carb... turned out the timing gears had nylon teeth, and the timing chain stripped them all off sending them into my oil pan and bending all my valves