Car is back firing!!!

Hello, I have a '90 teg and noticed that it seems to have a back firing problem. The only time it back fires is when I am cruising at a steady speed, let off the accelerator and then if I just tap the accelerator, a pop will come from the tail pipe. I can do this repeatedly and pretty consistantly. Like if I'm cruising down the road and I tap the accelerator, take my foot off, tap again, take my foot off, tap again, it will pop almost every time... Any Ideas on what would be causing this. I read in another forum that it could be the wire to the igniter in the distributor could be loose. any other suggestions.

I should also mention that I am running a straight pipe from header to exhaust. No cat or resonator. This wouldn't have anything to do with it should it?

its just back pressure and i wouldnt worry about it. I have friends with boosted cars that do the same thing. I think the reason being that you are just running it straight back with no cat. :redface:

Thanks for the reply. I guess I won't worry to much about it then.

I don't know if this is a related matter but if it is a back pressure issue, would that explain my weak low end power. I know these cars don't make max tq until above 5k but I feel a big difference from idle to 4500 rpm then after that, all hell breaks loose..

By that I mean starting in 1st gear, if I slowly accelerate from a dead stop, with my foot steady on the accelerator, from idle to 4k the car starts off slowly, but after 4k or so(without pushing any harder on the accelerator), the car will suddenly lurch forward and take off like a bat out of..well you know! same with 2nd and 3rd gears. I don't notice much of a kick after that since the car is already moving pretty fast by then... But does that sound normall for having straight pipe. Having a weak low end but good gains in upper rpm range???

Sorry for all the questions but I'm pretty new to all this...

Thanks,

Peace...

sounds like vtec??

um...worry about it. this seems like while coasting your car is running rich(allowing too much fuel into the engine) and when you press the accelerator b/c you have extra fuel you get a backfire. thats just what i think. and its similar for kids who boost....they put 550 injectors b/c when they run at 8-12psi you need fuel while boosting but when coasting you dont need that much fuel...so you end up back firing. it sound like thats your issue...thats just my opinion.

ok billab2ong, that sounds reasonable. But is it harmful to the engine? When I got the car, the tailpipe seamed to look pretty clean, but now, it is all black. So that would make sense if I'm running rich. So what is the solution for running rich? How do I lean it out more. Maybe the cone air filter is clogged. It is probably pretty dirty. As a matter of fact, I will go check as soon as I'm done here. I know for sure it isn't a K&N so I won't be able to wash it off.. My accord had k&n filter so anytime it got dirty, I just washed it. What do you people with non K&N filters do? Just replace it? I will probably order K&n for it soon....


Any more suggestions would be great

Peace.....

uh while we're on the whole straight pipe issue, I'm getting one on tues. and was wondering if I should really get it or just go with a cat-back?
What are the pros n cons of a staright pipe?
do the pros out number the cons? :eek7:

-Eli

well that lurching at 4000 - 5000 rpm in a non-vtec b18 is when the valves come alive an get good lift. If the lurch is really messed up then the valves are not opening enough under low rpm
I have done some valve adjustment to my 92 teg and it sounds similar to vtec because the higher and longer lift on the valves is just like vtec

your symptoms seem normal but if it is completely boggy under low rpm then have it checked out