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?
I would guess rich
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.
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.
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.
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.
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
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.
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.
I doubt it's the rockers. It has to be some sort of fueling issue.
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.
I'm going to do a compression test hopefully this week. Depends on work and weather.
Vinnie, didn't you put a new FPR on not too long ago?
If not, and the compression shows all cylinders acceptable....
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.
Compression test only tells you if you have good compression. If you do not have good compression it could be the piston rings, head gasket, exhaust valve not sealing, or intake valve no sealing. With the valves that could be either the mechanical seal between the valve and the valve seat, weak valve spring, incorrect installation of the valve spring (install height), pushrod length issue, or incorrectly adjusted rocker arm.
A leak down test is a more robust test but not everyone has access to one of those.
I think it is an issue of too much fuel however that may be the case. What is the temperature setting on the thermostat you are using?
Read the second paragraph on this site as there are some issues with the Cobra EEC. Also, read the fourth paragraph as it appears that the MAF from a 94-95 GT or Cobra can also be used with the X3Z EEC:
http://webpages.charter.net/darrell1/mustang_efi.html
I did a little more digging around and this is what we all know, the size of the injector is programmed into the EEC and the transfer function of the MAF is programmed into the EEC. The X3Z is expecting 24lb/hr injectors and an OEM 70mm MAF. The 70mm MAF's from the 93 Cobra, the 94-95 Cobra, and the 94-95 GT's are all 70mm and will work with the X3Z EEC as it is expecting an OEM transfer function from a 70mm MAF. Hopefully that will help as you can go scour the yards for a back up MAF and see if that helps any. Should be able to get a GT MAF for under $50 like here:
http://forums.corral.net/forums/fuel-system-related/1872857-oem-maf-95-mustang-gt.html
Darren
As long as he's running a 180* thermostat or 190* thermostat he should be fine. I've been running a 180* for years with no issue.
Hey Vinnie, you keep goin back to rocker adjustment If your to tight it will run like , If your loose they will chatter loud. With what you put in they probably will be louder than a normal set up. High ramp rates stiff springs "noise". Did you buy the $200 Lifters That were recommended for the cam? There close to being a solid set up. I can send you my leak down tester if you want to borrow it. If I can help you anyway let me know.
The EEC is expecting ECT temps that correlate with a 190 degree t-stat however a 180 degree t-stat will work as well. The problem is that these processors are over 20 years old and have a limited amount of processing power. When we provide inputs that are out of the expected range the EEC was originally programmed for the EEC goes into adaptive strategy mode which uses up more processor power so it limits what the EEC can do the more we drive it to use the adaptive strategy. That is all I wanted to point out with my t-stat comment for Vinnie.
Darren
I have a 192 degree thermostat in right now. I also have a 180 in the drawer. I do have the X3Z ecm, matching MAF and 24lb injectors. I also believe it's a fuel matter, and I was really thinking about a vacuum leak as Thunderjet mentioned to me. I will re-do the intake gaskets when the Tmoss intake gets here.
Kitz, I'll keep the checker in mind, but hang tight on that. s far as rockers, I ended up going with Scorpions. Brand new. Chatter may just be something that "IS".
When you swap lower intake take a picture of what the gasket looks like and/or if you have any oil in the lower intake runners. It could be sucking air from the lifter valley if the intake gaskets shifted, causing a lean condition and the computer to compensate by richening up the mixture.
I'll do it. I'll grab a few pics of the whole ordeal....I mean "process". LOL.
I'd almost suggest swapping the FPR first...as it's less work. Just a hunch...but likely not the problem. Hope it is though, for your piece of mind.
It's going to be swapped as well.
Maybe the rear lifter valley gasket is popped out just enough to cause vacuum leak? Just a thought.
Did you ever pull codes off this car?
Under hard accel there should be almost no vacuum, I think you're barking up the wrong tree with intake gaskets and fuel pressure regulators. I think that's wasting a lot of time Vinnie doesn't have. You need time on a dyno with a gas buttstuffyzer up the tail pipes. That will tell you what's what.
due to work and no time, I haven't done much since this post. Codes are on my list as well...literally, I have a list of things to do.It seems as though when I have things like this I need to tend to, it always happens at the last minute before I go back to work, then the weather starts to get bad. The car is running, so I will be addressing all of the ideas tossed my way, starting with the most external. Then working inward. I wonder about rings. just not sure. Wouldn't they be bad all the time, and not just under hard acceleration? I have a spare Explorer 5.0 in the garage. Thinking about going through it...new rings, bearings, timing chain, etc. It feels tight and smooth, great cross hatching. But in the mean time I am going to figure out why this engine is doing what it is doing.
Vinnie, Does it run good? Except the smoke?
I got to agree, he changed so much, it's hard to but blame in one spot or other. Put big heads on custom cam,and so on. To the point it needs to be tuned.
I agree Kitz. Ihoep to do that this summer. Yeah, that's a few months away, but, it is what it is.
Kitz, other than the smoke, it's doing pretty good. Not 100%, but pretty good. It'll get there. I have no doubt about that.
valve stem seals?
Vinnie is swapping a Tmoss ported GT40 lower on soon, which is why I suggested checking the intake manifold gaskets for leaks. If he wasn't swapping intakes I wouldn't have suggested it.
I know its frustrating, Just hang in there Vinn. Just putting some good mojo your way.
Thanks guys. Cold and raining today on my day off....of course. LOL. No worries, the ported lower is going to be here Monday. I hope to get into it next weekend. If not, well.... as soon as I can. The smoke didn't start until the head and cam swap. Crazy. I think I might go ahead and pull the heads, swap gaskets and valve seals (whether they are needed or not), Can't hurt, then see what happens. It doesn't make sense that it started when those parts were swapped unless it's a gasket issue or a seal issue. Hmmmm.......I gotta think on this a bit.
If the heads were brand new when you installed them then I doubt the valve seals are bad.
Tell us about the heads...all new parts, or used stuff that's been freshened up? Valve job? new seals?
Brand new afr 185's, I sold them to him.
what are the stats on the bottom end vinnie? Could be a little blowby or sticky oil rings? just a little seeping past the rings? sucking oil through pcv?
Yep, sucking some oil through the PCV. I have another XXX short block in the garage I'm gathering parts for slowly.