mattdel

Depends on your future plans. Personally I buy Crane ignition stuff for my muscle cars.

Levan

ok, I'll go with motorcraft I think. Thanks!

Levan

Hi guys,

This is going to be a real headache. I've changed a lot of things but this problem with backfiring is still here.

now I have:

new sparks
new spark wires
new ignition coil
new distributor

The only part that computer indicates on is this EGR valve.

Mattdel, what do you think, should I try MAF next?

Levan

Hi guys,

This is going to be a real headache. I've changed a lot of things but this problem with backfiring is still here.

now I have:

new sparks
new spark wires
new ignition coil
new distributor

The only part that computer indicates on is this EGR valve.

Mattdel, what do you think, should I try MAF next?

dawson1112

Before spending money on a new maf You should pull it clean it .
Just be careful not to break the filament. I usually just use a can of brake parts cleaner and blast it . The maf build up crud over time causing problems.

That code your getting for the egr not opening could be a vacuum leak either going to the egr control solenoid or the vacuum line coming back to the egr valve itself. So you should at least find out why your getting that code. It could also be that the egr valve itself has a bad diaphragm and leaking vacuum there or simply that the egr is so plugged with carbon that it cant be opened. A vacuum leak would send unmetered air into the intake and likely cause a high idle/lean condition, also can cause some popping or back firing through the intake.


Here is a thread from another site with some very good info ... scroll down a few posts and you will see a long post with pics , a lot of links and info on lean operation catagories...

http://www.stangnet.com/mustang-foru...intake.847678/

Levan

thanks for your info

We have cleaned both MAF and EGR, there were two sensors in maf. One of them got clean white color after cleaning while another one is still dark grey. Guy who was checking EGR valve told me that the diaphragm may be damaged and it's time to completely replace it. Should I replace both?

dawson1112

I would just plug the vacuum line that goes to the egr valve and be done with it. I don't even run a egr on my 94... You just want to eliminate any possibility of a vacuum leak. These cars run fine without the egr other than having a check engine light.

The last time I had my maf apart to clean it both filaments were dark colored . I am guessing that maybe the one that's white is damaged or corroded , but I cant be for sure. First thing I would do is take care of the egr if its leaking vacuum .

Levan

So it can run good without EGR valve? I can deal with check engine light, it's not a problem for me but some people say that if you delete EGR, you also need to remove its program from computer as well. Nobody knows how to do it here. Have you done this with your gt? If it's ok to disable EGR by just plugging the vacuum line, I would definitely think to buy new MAF and be done with it because I have tested it with MAF unplugged and it's running without any backfires.

dawson1112

I just run with the egr vacuum plugged check engine light on, The only reason pple want to tune the egr out of the program is to eliminate the check engine light. There is no need for it though. The only purpose of the egr is to circulate a small amount of exhaust gas back into the intake periodically to cool the combustion chamber a bit this is supposed to help with emissions by reducing the amount of harmful nitrogen's the engine produces. If you live in a state that has a strict emissions policy then you may fail the smog test, but other than that it has no effect on drivability. I don't see any difference in mpg one way or the other either.

Levan

ok dawson, thanks a lot for your help. So if not EGR, no backfire with disconnected MAF sensor could indicate that the maf should be replaced?