strange problem, need help

[NintendoKD]

ok, I will cut out all of the BS, and just tell you what I have done, and what I know.
Cleaned:
MAF, AIT, TPS, IAC.
I have also thouroughly cleaned the upper and lower intake manifolds and replaced all gaskets. I replaced upper and lower manifold gaskets "rubber ones"
I replaced the PCV, I also replaced the drivers side spark plugs and wires "I will replace the other ones when I pull the pass side tire" I have replaced the fuel pump and filter. Fuel test reads a consistent 30psi, with no dropoff during accel.

Now for the problem, The car doesn't run right, the exhaust smells like unburnt gas. I can disconnect the above sensors, as well as the EGR vacuum and nothing much changes, It still runs like crap, and no engine code. I have been told that this is due to a bad PCM, but I would like to be sure before I try to track one down. The vacuum leak has been fixed and there is a definite change in throttle response and the engine idles better, however it still runs like poo, and the exhaust still smells like gasonline. There is something else too, The cats sound as if there are mexican jumping beans inside. There is hesitation unless I put the throttle to the floor, and it will not hod a given speed in a higher gear. It is starting to shift badly, and I also noticed that when I first resealed everything that it ran great and had very little of the problem that it has now. It does this when the engine has not "warmed up yet" I also get similar results when I pull the neg terminal. I don't know what to do next. Any help would be greatly appreciated.

thanks,

Sgt Kevin A. Davies, USMC

 

[albi1cnobi1]

If you're smelling unburnt gas there's a good possibility you've got one or more bad plugs. Another possibility is a bad or plugged catalytic converter.

 

[koda2000]

when you pulled the spark plugs what do they look like? do all of them look the same or are certain ones black, sooty and/or wet? you need to look at all of them and remember which one came from which cylinder (use a piece of cardboard to keep track). it might be a bad/leaking fuel injector. I always doubt the PCM is bad. If your cats are making noise, they're probably toast (as in melted down). If you've been running rich (which you've indicated you are by smelling unburnt fuel) this will ruin the cats. An other thought is regarding your O2 sensors. Are they hooked up? have they ever been changed? If they send the wrong or/no signal to the PCM it will make your engine run too rich or too lean.

 

[NintendoKD]

If you're smelling unburnt gas there's a good possibility you've got one or more bad plugs. Another possibility is a bad or plugged catalytic converter.

cats sound wierd, so I'll pull those next, easy job, like some kind of light backfire or something. strangely, it will go away and the car will drive fine...... sometimes, but mostly not

 

[NintendoKD]

when you pulled the spark plugs what do they look like? do all of them look the same or are certain ones black, sooty and/or wet? you need to look at all of them and remember which one came from which cylinder (use a piece of cardboard to keep track). it might be a bad/leaking fuel injector. I always doubt the PCM is bad. If your cats are making noise, they're probably toast (as in melted down). If you've been running rich (which you've indicated you are by smelling unburnt fuel) this will ruin the cats. An other thought is regarding your O2 sensors. Are they hooked up? have they ever been changed? If they send the wrong or/no signal to the PCM it will make your engine run too rich or too lean.

cats will be checked first, easy enough to pull. What am I looking for? I can weld a new set of universal ones in. O2's will be next, next easiest, they are hooked up, but even if I disconnect one, no code, and no change.... well, not much of a change. still runs like poo. spark plugs looked good, recently changed, before I got it. The ones in there were the right ones too, I checked to see if they were the "shorter" pushrod style plugs. injectors will be last, it is seriously a PITA to take off the intake on this thing.

thanks,

Kevin

 

[Lube]

Continue to look for vacuum leaks. Running rich would be a normal response from the computer for this, as it richens up the mixture trying to compensate for the unexpected airflow.

 

[NintendoKD]

Continue to look for vacuum leaks. Running rich would be a normal response from the computer for this, as it richens up the mixture trying to compensate for the unexpected airflow.

where, and how?
I have used starting fluid and sprayed around the intake with no success. shoot, I just installed the thing with new gaskets. I did notice something, however, the diameter of the holes in the intake mani. and the diameter of the studs/bolts that go in there are vastly different. The studs/bolts ar very narrow and the holes are very large, I suppose that it is possible that the gasket didn't line up properly and seal correctly. I also didn't torque them with a torque wrench. This is mainly because I used anti-sieze, and torqued them in the correct torque pattern, twice to be sure there was no slop, and that the gasket completely squeezed down.

 

[koda2000]

re the spark plugs "looking good", if all 6 looked the same and not sooty (should be a light tan color) then it doesn't sound like you're running rich. ??? As far as the cats, if you take them off the truck and shake them, you shouldn't hear anything rattling around inside and nothing should shake out of them. the guts of a cat are a ceramic honeycomb that is treaded with different metals. there are no moving parts, they just heat up and are supposed to burn off pollutants in the exhaust. if you put too much unburned fuel, or oil, into a cat it gets too hot and the ceramic will melt and break up. If you discover a cat is bad DO NOT simply replace it without fixing the problem first, cats don't die... they're murdered. The O2 sensors "sniff" the exhaust and report back to the PCM so that it can adjust the pulse width of the fuel injectors to maximize efficientcy.

 

[Lube]

I also didn't torque them with a torque wrench. This is mainly because I used anti-sieze, and torqued them in the correct torque pattern, twice to be sure there was no slop, and that the gasket completely squeezed down.

There's clue #1. Always use a torque wrench. With anti-seize, reduce the torque by 10%.
Are you sure all vacuum hoses are reconnected?

 

[NintendoKD]

There's clue #1. Always use a torque wrench. With anti-seize, reduce the torque by 10%.
Are you sure all vacuum hoses are reconnected?

didn't have one handy, and I realize itreduces torque by up to 10%, which is why id did my round twice, won't hurt to check them again, and I connected all vacuum lines. I sprayed all around the intake mani and got no revving out of the ordinary, so as far as I can tell there is not a vacuum leak, however, everything that I know and my gut tells me that there is a vacuum leak. I most often second guess myself, which is the biggest reason why I am here. I plan to follow the advice given here, but I don't want to credit myself too much, perhaps there is something I missed.

Thanks guys,

Kevin

 

[NintendoKD]

bad injector seals??? I'm just throwing ideas out there now. I can hear a hissing from the middle of the dash while driving. O/D off improves shifting and driveability, I have to floor it to get it to go, but when I do, she moves well. Anything over 40 and it drives semi normal. It will not hold a given speed and lurshes, while holding "like it's hiccuping"

 

[NintendoKD]

going to try spraying again

 

[NintendoKD]

no vacuum leak?

I tried spraying again, no leak found. I hooked up a CODIS to it and ran an on board diagnostics full spectrum test, this is what I learned. When I pulled the dash, and ran an ohm test on the CEL bulb, the bulb tested good, however, it won't come on, not because the computer is bad, but because someone severed the wire going to it. "sneaky *******s"

The CODIS told me the rear o2's were not doing anything.
I put my hand over the exhaust and I found that I can do this easily and kill the engine.
The front o2's responded but very sluggishly and even after a 5 minute bout of 2500rpm's still did not function much better.
I have the following codes, not hard, because after clearing them they did not immediately come back. These are in order as I pulled them: P0720, P0156 P1131, P1152, P0175
These all point to the o2 sensors. I also checked injector activity with the CODIS, injectors were sluggish if even active, which is consistant with running rich, however, half were also pulsing very little if at all, which is consistant with running sluggish and lack of power, along with some of the other problems.
I connected the inductive timing light to see if the timing was off, it pulsed irregularly, on all plug connectors, as well as wires, mind you this is with new plugs and wires.
My thoughts:
The o2's are throwing off the computers balance, causing misfiring, overfuelling, and premature failure of the coilpack, the injectors, as well as fialure of the cats, "clogged cats" this is evident in the low exhaust pressure. This is also evident in the mini backfires inside the cats.

what do you all think? I'll know more when I pull the cats and o2's

Thanks,

Kevin

 

[albi1cnobi1]

My guess is O2 sensors, now that you have determined the CEL isn't working. I'd start there. It's a cheaper alternative to replacing the cats. If your mileage is up there it's probably a good idea any way.


Edit: Would have helped if I read the whole post. I think you're right in your thoughts on your problems. Running like that too long will definitely kill the cats.

 

[NintendoKD]

I replaced the rear o2's "it is a PITA if you don't have the right tool though". I used a big set of channel locks and some patience, the one closest to the frame was the most difficult to get to. I noticed some heavy deposits of carbon and whatnot on both o2's, however, the pasenger side sensor was by far the dirtiest and nastiest. I removed the NEG terminal ad turned the key to reset the map and turned her over, didn't start right away, but when I tried it again success. There is still a popping inside the cats "I assume they are quite clogged with something similar to what I saw" There is a change, however, and as far as I can tell shifting is better, and drieability has improved. I will replace the front two tomorrow, and pull the cats to see just what I am working with. I may just order an inline cat, or possibly hit the scrapyard to see what I can see depending on my findings tomorrow. I will know more on my test drive tomorrow. I will also take her back to the shop for some more tests tomorrow, as well.

 

[ranger7ltr]

This doesn't sound normal to me...

Fuel test reads a consistent 30psi, with no dropoff during accel.

On a system with a vacuum operated fuel pressure regulator, the fuel pressure needs to increase as the vacuum signal drops...In other words the fuel pressure goes up to as high as 40-43 psi, which is Fords' specification, as the throttle is opened and the engine speed increases...

I would retest the fuel pressure and pull the vacuum line off the fpr with the engine running and see if the pressure increases to 40 or higher... If it does then the fpr is working... if it really stays at 30 psi, you have a dead fpr and it is time to replace it...

 

[NintendoKD]

thanks

 

[koda2000]

re: fuel pessure. if the cats are clogged, won't that have an effect on manifold vacuum pressure reading?

 

[NintendoKD]

how for to fix cats? shake by the tail untiil they behave? rub thier faces in it? hide the litterbox? LOL Seriously though, what do I do with clogged cats?

 

[albi1cnobi1]

Not much besides replacing them.