torqued valve covers, now its running terrible!

[xploder98]

Well I think I finally found the problem. I found that a bad dpfe sensor can also cause a lean condition and those codes. So I did some testing. When the engine is cold the dpfe should read between .75 and 1.25 v it was .99, within specs. As the engine warms the v should rise to somewhere between 4 and 6 v. I let the engine fully warm up and it stayed at .99. And after warmed up, at idle, the v should be near 0. Once again, it stayed at .99-1 v. I think its lettin in too much air than it should. And I read another way to test it is to test it with the two tubes disconnected, connect your own tube (1 ft length or so) to the hi, probe the signal and the ground with safety pins, don't stab the wires just poke the safety pin in with the wire to the harness. Turn the key to on. Then with a voltmeter hooked to the sig and grnd, suck on the length of tubing you have attached to the HI side. It should climb up to 4.0-6.0 v and drop back down when you stop. The REF side should do the same but considerably lower. Well when I did this the REF side did what the HI side was suppose to and the HI side went from 1 v to .10 v which I don't think was suppose to happen at all! The first test I did was from haynes manual. The second test I did was from another forum. Here is the link http://www.ford-trucks.com/forums/342419-how-to-test-your-dpfe-sensor.html

 

[xploder98]

Well, I thought wrong. Replaced dpfe sensor, no change. Tested egr valve, held vac like it should. Tested egr vac regulator, tested good. Tested tps sensor, tested good. I'm gonna return the dpfe sensor and pik up a couple cans of starting fluid to check for leaks, again, and go from there. As of now. Everythings smooth, seems like there may be a slight power loss, a slighty rough idle and a slight miss. Not bad tho. At all. Hooked up a timing light and there all consistent with eachother, it just seems like there all missing a beat in between blinks. Still have codes p0171 and p0174

 

[xploder98]

Anybody out there??? :scratch:

 

[Turdle]

How about the air intake tube -

it has to be sealed tightly between the MAF and throttle body -allowing no unmetered air to enter.

Look for leaks and cracks, also, the oil breather tube may be allowing too much air into the tube it is is not sealed well.

 

[xploder98]

Yah I was thinkin that last night. Gonna inspect it and hit some areas with starting fluid.

 

[Sedition]

Chain tension

When you had your valve covers off, did you check your chain tension, paying particular attention to the rear chain?

 

[Sedition]

When you had your valve covers off, did you check your chain tension, paying particular attention to the rear chain?

In your last post it sounded like you have very similar symptoms to what I have. I am currently in the middle of repair/exploration mission to remove foreign material and advance the timing in my right cam so it will become "back in time" with the rest of the timing equipment.

Here is a link to where I started posting with pics in reguards to the above

http://www.explorerforum.com/forums/showthread.php?t=271605&page=5

 

[joesilvia92]

im at a loss for words

 

[xploder98]

No. I didn't even look at em. Can that cause a lean condition? If I was getting a rich condition I figure it would be because of ignition/timing. But I'm getting lean in both banks and after everything I've done and tried all I can think would be left is a vac/intake leak I'm missing or not enough fuel, and I've already done a fuel pressure test and regulator test. Both tested good. I'm beyond a loss of words.

 

[Sedition]

No. I didn't even look at em. Can that cause a lean condition? ..........

I'm not sure

 

[Sedition]

Did you find your problem yet? A clogged oil pickup is something else easy to check.

 

[HiredMind]

The reason that your mileage sucks is that your engine controller (I'm new to Ford so I don't know what they call it - Toyota calls it an ECM) is detecting a lean condition (it's telling you that much) so it is pushing extra fuel to enrich the mix.

So now, you have to research what is causing it to detect that condition. It could actually be running lean, or a bad sensor could be fooling the ECM into thinking there is a lean condition when there isn't.

If it were a Toyota it would probably be the oxygen sensor. The first hit when I Googled "lean condition ford explorer" (ahem) was a page from this very site.

Hope it helps

 

[xploder98]

Well its been runnin and drivin ok but there's still a miss and mileage isn't that great. And I still have the p0171 and p0174. No other codes just those 2. Doesn't really seem to down on power. I wish there was some kinda ford tech list/chart of every possible thing that can cause those codes. Or all codes for that matter. Would make things easy.

 

[xploder98]

Btw I do have the infamous synch cam "chirp". I'm pretty sure that's what its called. There's a good thread about it here.

http://www.explorerforum.com/forums/showthread.php?t=161590&highlight=bird+chirp

However I had this problem, not as bad, before all of this. And I would think if it was bad enough to cause my mix to be lean then it would have its own code.

 

[HiredMind]

Well its been runnin and drivin ok but there's still a miss and mileage isn't that great. And I still have the p0171 and p0174. No other codes just those 2. Doesn't really seem to down on power. I wish there was some kinda ford tech list/chart of every possible thing that can cause those codes. Or all codes for that matter. Would make things easy.

Xploder, did you go through the things in that link that I posted?