Big Problem

[Nick56289]

So after the installation of BBBs and ported and poliched intake I am having tome huge problems. The car backfires a LOT and is literally shooting out peices of porous fiberglass type material from the exhaust. I am not tsure if this is from the cats or from the mufflers. The mufflers are the fart cannon type. The sedcond thing is that it is also misfiring a lot. When I cleaned out the intake ports on the head I let a ton of carb cleaner in them but that should have burned off by now. I also put dielectric grease on many of the electrical connecters including the DIS, MAF and IAB. Also I put dielectric grease on the coil packs. Also I used the copper autolites for spark plugs. Any help or advice would be appreciated!!!

 

[Kens1992mtxSHO]

Did you replace the plugs in the correct order?

ENGINE
123
456

COIL PACK

61
52
43

 

[Nick56289]

Yea i definetily have the plugs in the correct order. Also I should note that the gas in there has probably been sitting for about a month. I just looked at the chunks shooting out the exhaust pipes and some are a little sparkly and white and others are grey and look like pumice.

 

[Kens1992mtxSHO]

How much gas is in the tank? If anything go fill up and put some fresh gas in the tank.

 

[Nick56289]

Gas tank is almost empty. I will fill it up with some fresh gas but it doesnt seem like that will solve the problem.

 

[Kens1992mtxSHO]

O.K. Couple of other things...

How much dielectric grease did you put on the coil pack? Too much is not good.

Did you check your plug wires for defects?

Does this only happen under acceleration, idle, etc...?

Try disconnecting your MAF. Does it still run?

Are your ground wires secured?

Did you pull your codes?

Try these things and get back to us...

 

[St Louis SHO]

Make sure you installed the ground wire on the back of the intake.

 

[Kens1992mtxSHO]

Make sure you installed the ground wire on the back of the intake.

X2

It's easy to forget this. It's on the passenger's rear side of the manifold.

 

[Nick56289]

Thanks for all the replies. Ground wire is hooked up. No codes yet. I put a TON of dielectric grease on everything. Plug wires look ok but you never know, they worked fine before. Also it looks like part of the plastic on the #4 coil pack is chipped.

 

[Kens1992mtxSHO]

Also it looks like part of the plastic on the #4 coil pack is chipped.

That may be your culprit.

I put a TON of dielectric grease on everything.

Is any of the grease touching? What I mean is could the current be running to the other wires because of over application?

 

[Nick56289]

It looks like it is on some of the connectors. Could this cause a problem?

 

[Kens1992mtxSHO]

If the grease is on the connectors and it is running over into other connectors, then the current is travelling where ever you placed the grease or to the other connectors.

Also, if you placed a lot of grease on the plug wire ends for the plugs, this could be causing a misfire on that end also.

 

[Nick56289]

Alright im going to go clean up the grease and I will keep you guys posted. Thanks a lot!!!

 

[Nick56289]

Cleaned all the goop ff and tried again. Same problem. I also unplugged the MAF and didnt see any differece really. Im going to try and replace the coil pack and
plug wires and see if that makes any difference

 

[itwonder]

I know you checked , but the backfiring symptom sure sounds like you've got two plug wires swapped.

 

[Nick56289]

Ive quadrupled check the plug wire set up. I changed the coil pack with a new one and it still misses and backfires. Is the only thing left spark plug wires? I also did a valve adjustment, could I have messed up the timing? The number 5 spark plug seems to be a little blacker than the others. also what about the stuff coming out of the mufflers, would bad cats cause a misfire like this? I could have fouled the cats when I started it up with a bunch of throttle body cleaner in it. Any help is apreciated because im running out of ideas.

 

[Kens1992mtxSHO]

You could have fouled the plugs. Also inspect the plug wires carefully.

 

[Nick56289]

I know you checked , but the backfiring symptom sure sounds like you've got two plug wires swapped.

Alright your a genius. I quadrupled checked for the wrong thing. Why does the firing order go 123465 and not 123456. Im an idiot but I dont care because my SHO works now. 3.2 MTX ,y pipe, BBB', FULL port job for the upper intake and the head where the intake runners attach, exhaust, reinforced motor mounts, Aluminium subframe bushings, Quaife. This thing goes now! Im excited! Thanks everyone who helped out

 

[Kens1992mtxSHO]

Alright your a genius. I quadrupled checked for the wrong thing. Why does the firing order go 123465 and not 123456. Im an idiot but I dont care because my SHO works now. 3.2 MTX ,y pipe, BBB', FULL port job for the upper intake and the head where the intake runners attach, exhaust, reinforced motor mounts, Aluminium subframe bushings, Quaife. This thing goes now! Im excited! Thanks everyone who helped out

Got pics of your SHO??

 

[Nick56289]

Ill put ome up in a few days when I got time between work and school. Thanks!!