I have a 94 A4 mods in sig, last week I was at the track for the first time with the nitrous, it ran well 12.5's on my final run of the day I stage and soon as I launch there is a loud pop and my car stalls and smoke is pouring out from the hood I run out and extinguish the wire looms that were on fire, the elbow blew off the throttle body along with the nitrous nozzle and my panel filter was bubbled out. the timing was retarded 2 degrees for these runs. So I trailer it home and fix the wires put everything back in place check the spark plugs and it was running fine, now once in awhile it will be missing backfiring and knocking at full throttle but it idles fine and no weird noises. could it be the mass airflow cold air sensor??? help please I'm going nuts

 

Check everything attached to the intake manifold, including the throttle blades. They can get bent. Check the MAP sensor and the MAF sensor. Make sure all the vacuum lines are still attached. Make sure you didn't tear the inlet elbow. Make sure the IAT sensor is still in the elbow.

Then if you get it running right, start checking the nitrous components. Possible you had a leak in the the nitrous solenoid or the fuel solenoid.

 

ttt

 

thats why u dont buy zex kits they suck

 

thanks for the help next time you break something I'll be there to make a smart *** comment.

 

ttt

 

Did you check the stuff Fred suggested? I'd recommend getting a window switch, assuming you don't have one.

Dave

 

Might have better luck in the N20 section. good luck.

 

yes everything is hooked up and I know my stuff about cars but I do not know what a window switch is exactly...?

 

THats why you blew up buddy. You prob sprayed at too low of a rpm, my window switch is set from 3k-5400..........

 

It's a switch that comes on and off within a certain RPM range. Like Hawk says, you don't want to spray at too low RPM or too high, so a window switch is often used to make sure you don't hit the juice too early. A backfire is a common result if you hit it at low RPM.

Dave

 

well I didn't exactly blow it up it just blew back out the intake but I do understand what you guys are saying thanks

 

It could be a spark plug. I was having what seems to be a similar problem.... Idled fine and city driving it was just fine but when accelerating onto the freeway it would misfire. I took it in, got new sparkies and now everything is fine. Hope that helps... I hope it gets taken care of.

 

thanks man I really appreciate the help, this weekend I'mk gonna pull all the plugs and take a gander