Loss of power; runs like crap

[pitaSHO]

OK, Here is my situation. My 93 MTX runs like garbage. I have done a full rod bearing-front 60k-top 60k. I replaced the cam sensor and pulled the codes. It gives me a Cylinder 6 code. ?????? I checked and re-checked the plugs to make sure they were in the right order. I replaced the DIS. I don't know what else to check. If I don't let the car warm up it won't go any faster than 5mph. If I floor it, it boggs down. If I nurse it, I can get it to run; after it warms up. And I get 11 mpg. Any suggestions??????

Chris K.

 

[Vnuk1]

Checked your MAF?

 

[shoshirtsandhat]

Try unplugging the mass air flow , if you notice a difference then that may be the problem

 

[rubydist]

.... pulled the codes. It gives me a Cylinder 6 code. ??????
Chris K.

You mean that the koer test on the cylinder balance reports cyl 6? If so, that means you have a bad plug or wire on cyl 6, or you have a more serious problem like sticky rings, etc.

However, I know from experience that one cylinder with sticky rings failing the cylinder balance test will not result in the crappy performance that you describe, so there has to be something else going on.

Fuel pressure okay? (fuel pump, filter, fpr) When you changed the cam sensor, you didn't get the little metal sensor wheel turned off a half a turn did you?

 

[pitaSHO]

Yes, the KOER test turned up the cyl 6 code. I changed the spark plugs and wires, so I'm pretty sure it's not that. Will a bad MAF cause a cyl 6 code? Not sure how this is connected....

Also, when starting out in first gear it sounds like a cylinder popping if I don't throttle it right (don't know how else to describe that sound....) like when the engine gets too much of a load or something....

Fuel filter replaced. Not sure about pressure at the rail. Will pulling the codes show a bad injector?

 

[pitaSHO]

Could it be the IAB?

 

[jpSHO]

Sounds like maybe a bad fuel pump.

 

[pitaSHO]

It feels like two spark plug wires are crossed, but I triple checked them. I thought maybe I got the timing off, so I tore it apart and reset the timing belt (yes, I used the 3.0 hash on the belt). Still no better. If it was the fuel pump, it would either work or not, but it would still fire on all six. Not sure it is....

 

[jpSHO]

A fuel pump can work and not provide enough fuel which I think could cause misfire symptoms. To be sure I would check the fuel pressure. It's easy to do and that would eliminate the possibilty of a bad fuel pump.

 

[itwonder]

Check for a bad coil pack. Of course, #6 is the plug people usually get reversed.

 

[pitaSHO]

Changing the coil pack was one of the first things I did. Nothing changed. It had this issue when I bought it. There was a receipt in the glove box from the po from Ford that said it had blow by on all six. Loss of power at WOT. I checked compression, and compression was good on all cylinders....

 

[rubydist]

I've put in new plugs and had one turn up bad, and I've had new plug wires be nfg, so don't assume that the plug and/or wire on #6 is good. At least swap the plug with a different cylinder to see if the problem moves or not.

 

[pitaSHO]

I'll try that. I swapped the MAF: didn't change anything....

 

[rubydist]

Its also possible that the pcm is sick. I've had that happen on other applications, where the computer didn't work right, but wasn't completely dead. Do you have one of those to swap out?

 

[pitaSHO]

Yes, I do. I'll try that tomorrow or something. Thanks for the idea.:thankyou:

 

[pitaSHO]

Well, I broke down and took the car to a good local mechanic. The CCRM was rusted and corroded beyond repair. When that gets fixed he says he can continue the diagnostic.

Chris K.

 

[gmail]

the ccrm needs to be a ok ground to the body.. clean that up.
my guess from as it sounds is timing. or possibly check grounding strap, dis bolts, cross over tube where dis sits bolts, clean all grounds, check and recheck all grounds.
check all plug wires and recheck them.
use some carb cleaner on all rubber hoses, intake areas including the part that bolts to the head.

i hate to say it but dont trust mechanics they dont know jack on these cars for the most part.
number 6 id be thinking the injector isnt firing if i got that code unless i heard some knocking.

also make sure the firing order is right check it several times.
heres a link to the right firing order.
forget chilton and haynes they are wrong.

http://www.shoforum.com/showthread.php?t=69573&highlight=firing+order

 

[pitaSHO]

I have rechecked all you have mentioned. I even reset my timing belt because that's what it sounds like, but that didn't fix anything. Unless somebody got in and put a cam in wrong or a cam sprocket, I'm still stumped on that one. We'll see what the wrench monkey says later.

A mechanic may or may not know how to fix our cars, but diagnostics should be basic no matter what the car. That's where I'm at right now. They haven't done anything more than pull codes and run diagnostics. That's how they found the CCRM. I probably could have figured it out eventually, but between house hunting and getting ready for my little baby girl in April I just don't have time or energy to fight with it right now.

Chris K.

 

[pitaSHO]

I took my car back from the mechanic because he wanted to charge me $230 to change a cam sensor... I was able to drive it back to my friend's place and decided to do some trouble shooting on my own. I checked my cylinder compression and this is what I found:

150 150 150

150 40 150

I was not getting enough compression in cylinder 5. Crap. So I tore the head off to check for a bad valve or a blown head gasket (the car was overheated before I bought it) and they both looked fine. I know. Lots of work. I then noticed a carbon build up on the top of the insde edge of the cylinder. Mike said that if I have a bad ring I can get blow by and no compression. This would explain the froth I have been getting through the PCV system and oil in my intake (the tube between the throttle body and air filter) due to the crank case being under pressure. So now I have to drop the pan and pull the piston. The cylinder walls look perfect. No sign of scoring or any gouges at all. Baby butt smooth. Hopefully after I hone the cylinder wall and replace a piston and a set of rings it should run.

The amazing thing is that I am only into the repairs $150 in parts so far. The rest is labor. Amazing.

Chris K.

 

[rubydist]

Others have reported that they pulled out the sticky rings, cleaned up the ring lands, reinstalled the old rings without any honing or anything else and it ran like new. You might consider that....