i have a '98 w/ air mods and 50shot wet nitro...i ran it the other night and it instantly backfired twice...i parked it and turned it off...tried to turn it back on and the rpms went up, down, up, and then it stalled...that happens every time i try and start it now and the only way it doesn't stallout is if i give it some gas...even then it'll stall when going from reverse to first...but back to the story...i replaced my spark plugs w/ stock ngk's (they were stock before too), and it still is having problems...oh, and one more thing -i can't go over 4000 rpms no matter what...?!?...i talked to a person at a shop who has nitro, and he said that its either a blown gasket, valve, or bent rod and that i should get a compression test done on the chambers to see if its ok and then go from there...any other suggestions? if blew a piston, what then, titanum?? anyone know of any websites?...thanks, i'll post this in the nitro section too
#314, "RE: engine trouble" In response to Reply # 0
hey. i have a leak in my head gasket and that wouldn't be causing your problems even if it was blown,...i don't think. it should start up easy if it is blown because it is losing compression. just to make sure look at the engine and see if you see a little or lot of oil coming out of the heads. i don't know too much about rods or anything but i doubt that you would blow a rod or piston from the 50 shot nitrous you have. unless something went wrong with it or you had the rpms over red line. was it acting up before? better hope it's not the valves either because those can cause a lot of damage. right now my car won't even start. have no idea why. might be something with the fuel, the thing is i can't start it to take it anywhere to get checked. that sucks later
#315, "RE: engine trouble" In response to Reply # 1
The only time I know of where I couldn't go over 4000rpms is when a parameter was so far out of spec the PCM wouldn't allow the engine to be run above 4000rpm (it was cam timimg too far off in my case. Fixed it and it revved fine). I wonder if the backfire bent the throttle plate since your having trouble idling and stalling.
#316, "RE: engine trouble" In response to Reply # 2
If the car wont let you pass 4000 that means its running very rich and it could be in safe mode... is the CEL on? is your air filter swollen from the backfire??? well, if you do a compression test and it turns out fine then you mostlikely just blew a MAP sensor... had it happen to me twice and its a pretty expensive sensor...
#317, "RE: engine trouble" In response to Reply # 3
LAST EDITED ON 08-Apr-01 AT 10:48 AM (PST)
the service engine soon light is lit up all the time now, i'm not sure about the airfilter or throttle plate, but just to clarify, by backfire i mean it came out the exhaust, like two LOUD pops...how much is the sensor?, my guess is it wouldn't be as expensive as new pistons etc...? and it has backfired once before about 3 months ago, but nothing happened afterwards and everything worked fine, i'm taking it in tomorrow and i'll tell everyone how it goes
#318, "RE: engine trouble" In response to Reply # 4
the two loud pops is due too detonation and running lean when you were squeezing nos even running turbo on a hot day on high boost you will hear a pop due too detionation I hope itz something minor keep us posted
#320, "RE: engine trouble" In response to Reply # 0
LAST EDITED ON 12-Apr-01 AT 05:57 AM (PST)
If you want a MAP sensor, I can sell you one of mine. I have the extra MAP sensor because I have whole spare 420A engine. I guarantee that it will work too. I personally saw the engine run before it was taken out the car (it had a rod bearing going bad). If you are interested make me a reasonable offer. BTW its also out of a '98.
