Back fire after adding K&N?

[Brett]

Possibly. I honestly don't know the location on a Jeep! But it will be on the intake manifold. It will have a steel tube from it to the exhaust manifold. It could have an electrical sensor on the end of it (which would pull a code if it didn't move when it is supposed to, or moved with it isn't supposed to). It could have more than one vacuum line hooked up to it, one for open and one for close.

Take a picture of what your thinking, and we can say yeah or neah....

oh..the steel tube....uhh .....I removed that when I did my exhaust manifold cause it was cracked. Hadn't made a difference that I had noticed though.....

 

[Devel]

last time i checked cherokees didnt have egr valves, they are controlled some other way. tryed to find it in auto one day in highschool and i just didnt exist

 

[Brett]

last time i checked cherokees didnt have egr valves, they are controlled some other way. tryed to find it in auto one day in highschool and i just didnt exist

87-90 Renix 4.0's do

 

[DOSS]

Thats your EGR valve though I doubt that is causing your backfire

 

[Devel]

87-90 Renix 4.0's do

lame.....

 

[waynehartwig]

oh..the steel tube....uhh .....I removed that when I did my exhaust manifold cause it was cracked. Hadn't made a difference that I had noticed though.....

It did make a difference Now that the tube isn't there, when the EGR valve opens, it is a nice solid vacuum leak.

 

[waynehartwig]

tryed to find it in auto one day in highschool and i just didnt exist

Where were you then?

 

[Brett]

It did make a difference Now that the tube isn't there, when the EGR valve opens, it is a nice solid vacuum leak.

I was reading on NAXJA that some people seem to just remove the EGR and block off that that area....is that a big emissions problem or would that be okay?

 

[waynehartwig]

I was reading on NAXJA that some people seem to just remove the EGR and block off that that area....is that a big emissions problem or would that be okay?

That's a question for the emission guys... Functionally you would be ok. But legally I would say no, but I honestly don't know for sure. I think you have to keep all of your original smog equpiment in place and in working order to pass a visual inspection.

 

[Devel]

Where were you then?

it was on a 96 Jeep Cherokee, 4.0 Auto. there was no egr valve, my teacher swore up and down there was until he came and looked at it and couldnt find it, checked on shopkey and it showed now egr valve on the jeep. my 02 TJ doesnt have one either

 

[waynehartwig]

it was on a 96 Jeep Cherokee, 4.0 Auto. there was no egr valve, my teacher swore up and down there was until he came and looked at it and couldnt find it, checked on shopkey and it showed now egr valve on the jeep. my 02 TJ doesnt have one either

This was what I was commenting about in your post:

"in highschool and i just didnt exist"

...It seems you must have missed a T...

 

[lilsamiman]

just a thought, check your spark plugs. Perhaps one is craked and the spark is jumping out of the porcilin rather than running down to the electrodes. I have seen it happen before, just like your problem, under load.

 

[Brett]

just a thought, check your spark plugs. Perhaps one is craked and the spark is jumping out of the porcilin rather than running down to the electrodes. I have seen it happen before, just like your problem, under load.

Easy enough to check

 

[waynehartwig]

just a thought, check your spark plugs. Perhaps one is craked and the spark is jumping out of the porcilin rather than running down to the electrodes. I have seen it happen before, just like your problem, under load.

Good call... Anything like this. A dist cap that has a lot of carbon build up, or old plug wires that cross each other, or...? Maybe one of your plugs has a really small gap?

 

[Brett]

Good call... Anything like this. A dist cap that has a lot of carbon build up, or old plug wires that cross each other, or...? Maybe one of your plugs has a really small gap?

It's possible. I gapped them all when I did them, but I suppose I might have knocked one around a bit. I'll check them later. It's probably time to change them out anyway. It's probably been two years since I did the wires, cap, rotor and plugs.

 

[waynehartwig]

It's possible. I gapped them all when I did them, but I suppose I might have knocked one around a bit. I'll check them later. It's probably time to change them out anyway. It's probably been two years since I did the wires, cap, rotor and plugs.

Yeah, cuz anywhere you have a smaller gap will jump before the bigger one, especially in a loaded condition. Which could be anything, cap, wires, plugs, etc. And if that arc jumps when it's not supposed to, you have yourself a misfire.