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Topic: Gray smoke.... (Read 7581 times) previous topic - next topic

Gray smoke....

I've had this under heavy throttle....Gray smoke. Not dark gray, just gray. While driving at any speed, with no heavy throttle, no smoke. I pulled the plugs, they are a little black, and the electrodes are brownish. The oil looks good. Running rich? Head gaskets?
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Gray smoke....

Reply #1 –
I would guess rich
Mike

Gray smoke....

Reply #2 –
My fuel pressure is right at 40psi according to the gauge. Should I back it down? I also need to install the new O2 sensors.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Gray smoke....

Reply #3 –
I'm going to re-adjust my rockers hopefully tomorrow according to the instructions from a local shop who does a  ton of high performance 5.0 cars. I'll report in when I get them done and test it. Hopefully tomorrow after work.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Gray smoke....

Reply #4 –
Is it a lingering smoke?  I've seen lots of new cars particularly ecoboost engines do this, but only under strong acceleration.  I imagine the power enrichment the PCM is doing is responsible for this; how's it run when you're seeing grey smoke?  Also, since you've gotten you're new engine running, have you done any tuning?  The A9x computers have a stock tune, and no matter what you do with the MAF, you can't get away from the fact that the PCM is fueling it as if it were a stock engine.  That, and a calibrated MAF throws off the load calculation, and the load calculation affects spark timing and fueling.

Gray smoke....

Reply #5 –
it has an X3Z Cobra computer and matching Mass Air mter. I'm goint to do a little rocker adjusting, then see what happens. I traded an intake I have to TMoss for a ported lower for mine. Once that's on, I'm going to take the car to me friend Jeff and have him go through it and make it as it should be.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Gray smoke....

Reply #6 –
You should be running 39 psig of fuel pressure with the vacuum unplugged. When you step in it you should see a slight increase in fuel pressure. Mine goes to about 44 or 45 psig at WOT.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Gray smoke....

Reply #7 –
I'll be double checking fuel pressure after work. MAY do the rockers this evening. Depends on when I get home. I can check fuel pressure in the parking lot before I go home. It'll get figured out eventually. All this  does eventually.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Gray smoke....

Reply #8 –
Gray gray smoke, I'd also guess fuel. Light gray, I'd guess head gasket. Best of luck anyways. Let us know how it goes.
1988 Mercury cougar XR7- 302 bored .030 over, gt40p heads, F303, AlexsParts spring and seal kit, explorer upper and lower intake, 70mm tb, maf conversion, 75mm maf, fenderwell cai, 24 lb injectors, T5 conversion, bbk h pipe, Slp lm, 3.73 rear, 4 wheel disc conversion, 5 lug conversion. :D :D

Gray smoke....

Reply #9 –
I doubt it's the rockers. It has to be some sort of fueling issue.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Gray smoke....

Reply #10 –
I'm thinking fueling issue as well, but not sure. With all the black build up in the exhaust tips I'm thinking it's rich. Same issue the car has been having.I used the Cometic head gaskets. I don't guess that reallyu means much. I torqued the head bolts (ARP) to spec. I am growing to dislike this stuff these days. Once the engine is dialed in, I believe I'm done with any and all things drivetrain related. LOL.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Gray smoke....

Reply #11 –
Quote from: vinnietbird;443577
I'm thinking fueling issue as well, but not sure. With all the black build up in the exhaust tips I'm thinking it's rich. Same issue the car has been having.I used the Cometic head gaskets. I don't guess that reallyu means much. I torqued the head bolts (ARP) to spec. I am growing to dislike this stuff these days. Once the engine is dialed in, I believe I'm done with any and all things drivetrain related. LOL.

You could run a compression and leak down test. Then you'd at least know the head gaskets are sealing good. If they weren't sealing you would have other issues (coolant disappearing, coolant being forced out the overflow/radiator, coolant in the oil) besides smoke.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Gray smoke....

Reply #12 –
I'm going to do a compression test hopefully this week. Depends on work and weather.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Gray smoke....

Reply #13 –
Vinnie, didn't you put a new FPR on not too long ago?

If not, and the compression shows all cylinders acceptable....
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

Gray smoke....

Reply #14 –
i had a factory FPR on, then swapped my Kirban back on. I am going to return a factory FPS on. I have a known good FPR from a Lightning I'll install.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..