bizerk1

so sometimes when im driving I get a problem and was wondering what it is. When i floor it going 20- 70 when it hits 70 the rpm will be at 5300-5500 and will just backfire alot and the tires will spin alot, but i can still floor it fine from 85 -140. bad spark plug is what im thinking so i think it needs tune up. Any one know??? its a 94 z28 a4, short ram intake , catback and cam and hurst shift kit

bizerk1

is it optispark ??? help

idformula

Do you have acess to a scanner? Obd1 can trip codes, but not set off the ses light, at least its done it on my car.

bizerk1

no i dont

jaycenk

iTrader: (1)

Go to autozone or advanced and have them scan it. Kind of odd that it only will do it at the top of second gear. Are you sure the trans isn't slipping and causing the engine to hit the rev limiter?

Paul Bell

iTrader: (9)

You're not giving us much info. When you floor it it holds the gear and it won't shift?

RedHotG8

iTrader: (1)

Backfiring means the timing is off, so more than likely the timing chain is stretched. That causes the timing to vary under power. It could also be a bad opti-spark module.