What causes a backfire through the intake? Could somebody explain it? (Mine did it a couple of times in the days just before I changed my fuel filter.)

(Also, since I'm thinking about it, what causes a backfire through the exhaust?)

 

How can you tell when one comes from the exhaust or intake ? Do they sound differnt ? Is one louder ?

 

Timing is the biggest culpret.

Typically the Intake is LOUD, Acompanied by a fireball for those that have carbs/TBI

Whats your timing? Set it to 12-13* BTDC alot of people here have cars that like it ALOT better then the stock 10*
Also remember to disconnect the ESC Plug before you set the timing or its gonna get all screwed up. Reset the Comp too after done, it'll throw a code at ya

 

I was having problems with my '91 3.1 (126k miles) for the last week or two. It always started very quickly on the first try and then suddenly decided it didn't want to start until about the forth try. It also started stumbling at lower rpms and even stalled on two occasions.

So I changed the fuel filter and checked the timing. The timing was right on 10 degrees. The car started and ran good for the rest of the day.

Now the thing is acting up again. Any ideas? (other than moving timing to 12*) The car seems much better after it is warm but is hard starting/stumbling when it is cold.

I changed the coil, cap/rotor, wires, & plugs last fall and havn't really put that many miles on these new parts. I looked at the cap/rotor and one plug and they still basically look like new.

What should I look at next? Is this problem most likely fuel related or spark related? Where can I go from here? I need my car to be reliable because I have to drive it to work everyday.

Any help would be greatly appreciated.

 

you can clean the IAC vavle port(Passanger side throttle body, held in by 2 allen screws). that might help some, but taking it to 12 would be alot easier and fruitfull.

 

I agree with Hunter, I moved mine and the back firing ceased.