My 96 Cobra has recently started having some problems. I'm wondering if someone can help me make sense out of it. I'm a pretty smart guy and can fairly easily follow a logical path, but I lack the hands on mechanical experience I guess.

It has K&N filter, C&L 80mm MAF, BBK twin 65mm TB and a Walbro 255lph fuel pump. Ignition is all stock except NGK TR6 plugs (colder because of the NO2).

Soon after I bought the car (a few days) it developed an occassional miss during low rpm acceleration. I called my friend, who I bought the car from and he claimed the IMRCs probably just needed to be cleaned. I've posted around and asked a lot of questions and I just don't see how that's going to cause a miss. After driving the car he was convinced it was a fuel issue although he didn't really convince me why he was so sure.

After another month of driving the car, it's gotten progressively worse to the point that now it's parked. The car misses so bady you can't drive it. I had it hooked up at AutoZone and I don't remember the specific codes, but it was lean on banks 1 and 2, misfire on cylinders 1 and 3.

I pulled the MAF out and it was covered in carbon. It had just been cleaned when I bought the car (I was actually there when he did it). I've cleaned it again with CRC MAF cleaner. I changed the plugs, the plugs we 1 year old and were covered in ash, all of them. At the recommendation of several friends I went to NGK TR55s. I've ordered Borg Warner plug wires and they should be in tomorrow. Oh, I changed the fuel filter too.

So, what else should I take a look at here? Is the carbon in the MAF a cause or effect of the rest of the problems? It's easy to see why the MAF being full of carbon would affect engine performance, but what caused the carbon to build up so quickly in the first place? Same question for the ash on the plugs. Could this be an injector problem?

The parts houses are quick to tell you to start replacing things.Replacing the MAF was their first suggestion, but the MAF didn't throw anycodes. It maybe the MAF but it didn't throw any codes and I'm just not convinced yet. I'm not abig fan of the idea to just throw money at it until it's fixed.

Help would begreatly appreciated!

 

go to your local auto zone and see if they have a fuel pressure gauge to borrow. if so try there first. i've seen many of those walbro fuel pumps fail, that could be your problem. worth a shot checking the pressure and then go from there.

 

i doubt ur having fuel problems.coils might not be good?

 

Okay, turns out the plugs didn't have ash on them, but was Never-Seize compound it seems. I somehow doubt the problem is the fuel pump, check me to make sure this makes sense. Cylinders 1 and 3 don't miss all the time, more like 50-75% of the time, less at higher RPMs. If it was fuel pressure, wouldn't it miss more at higher rpms? I'd think this was the case, but maybe not. I'm certainly willing to check anyway.