I did a short burn out the other day and immediately after the engine started putting out black smoke and misfiring.

It seems to smooth out at about 3k rpms but anything less than about 1/3 throttle and it misfires. When I start to accellerate it coughs and then runs ok.

All the plugs on the passenger side are are burning black (no oil on them). The straps are burning clean but the electrodes are black. The drivers side is buring ok.

No engine noises.

The wide band is stuck on 15.5 or so again. I've never trusted it.

The fuel pressure is about 50 at idle, goes up slightly when the throttle is moved, then back to about 50 (might be over 50 but that's the best I could see from where I was)

I had problems with the fuel pressure regulator a while back having left out the small rubber O ring when I put on the Radix on. When I discovered that problem and then put it back together with the small O ring installed I had the feeling that I'd put it together without the large rubber gasket that's supposed to be in there. I haven't removed the fuel pressure reg yet to see if the gasket is in there... don't know if it matters since it was running fine and only the right bank is burning black.

Removed the O2 sensors and they look ok. I had the stock one so I put it back on the right side to see if it runs any differently. Haven't started it yet. The cat simulators are still hooked up. Unplugged the puter to so it might forget the problem. I did get a 174 code once since this all started.

Took the plugs to a friend who knows engines but not Gen III engines and he thinks I need a slightly hotter plug. I'm running NGK (R below the NGK) TR55. He says to gap at about 45 when I get the new plugs. Any plug recommendations?

Any suggestions? The problem started immediately after I let off the gas after the burn out. Was running smooth prior. Suggestions appreciated.

 

The gap should be about .033-.037"" for a boosted engine or you run the risk of blowing out your spark. The TR6 is the plug of choice for FI too. This is what most are running at 5-10psi levels Jim. Hope this helps some. Sounds like your running pig rich for some reason. Maybe a dirty MAF or bad sensor somewhere? Wish I knew more to help.

 

When I started it earlier tonight it spit out black soot onto the ground in back of the exhaust and around the edges of the tail pipe.

Dirty MAF? But the problem made itself known all at once right after I let off the throttle after the burnout. Maybe the MAF just got dirty enough to begin to cause a problem?? I'll check that out tomorrow. What does a new MAF cost?

TR6 plug. Is that what I should be running? Maybe .35 gap?

 

Damn Jim I hate to hear that, I know you have alot of work into that truck, I dont have a clue what the problem is but, maybe time for a 6L swap?

 

i belive autolite makes a good fi plug also (0.030-0.035)

 

Fouled a few plugs or possibly your fuel pressure regulator has gone bad.
Good Luck.

Jim

 

Sounds like you've got a badly fouled one or two. At low RPM this will snowball into a worsening situation because the misfires cause unburned fuel and oxygen to exit through the exhaust. The O2 sensor sees it and thinks lean because it only looks for oxygen, not unburnt fuel.
If you do not have access to OBD-II scanning equipment you can still tell alot from pulling the plugs. If it's just one side then you can totally dismiss everything induction related. On the other hand, if it's just one bank fouling out then start with the plugs, then coils, then the O2 sensor itself, compression, etc...

 

I noticed in your first post that you got a "174" code, which is a fuel trim too lean, bank two. You could have fouled a couple plugs, then that is messing with the 02 sensor, causing it to dump some fuel in like James B. said.

 

The crazy little bastard what lives in the back of my head is talking about: 572 crate engine, Coan trans, Ford 9" fabricated rear w/4 link, tubs, dual 4" exhaust, fuel cell in the bed. Big FUN!

I'm trying to not listen to him but he's getting louder and he sure talks some tempting ****. He also wants as cigarette and would love to have a drink and do some dope.

I'm going to take the fuel pressure regulator out and see if that gasket is missing. Change plugs but I still don't know why one bank is running so rich?

 

All four plugs on the right side were very black so I'm changing plugs. NGK says to go with a TR4 at .40. Anybody know anything abut this plug?