2004 Ford Explorer 4.0 Rough Idle VIN K

Ok guys I have a 04 explorer, it had a rough idle to it, it has no codes in it and the check engine light is not on .

The first thing I did to it was clean the throttle body on it it was coked up really bad it didn't help it.

I found the TSB on it for a rough idle and a factory Ford reflash, I explained the situation to the customer and it he returned it to Ford for the reprogram still didn't fix it.

So he brings it back to me and I perform a smoke test on it come to find out the intake gaskets are leaking at the #3 cylinder is really bad. So today I installed the intake gaskets its still idling rough. Still has no codes in it.

I pulled 4 and 5 plugs just for a quick glance they appeared to be clean and fine both cylinders had 170 psi of cranking compression.

After that I reinstalled the smoke machine smoked the engine again, no leaks besides the typical ford EGR valve.

My next step was to hook it up to the Modis and perform a lab scope anayalsis on it which I did. I did a single cyilnder scope on each cylinder then I did a parade scope on all the cyilnders at once. I really did not notice anything out of the ordinary. I slowed the KV patterns from 30k to 10K so I could get a very clear defination of the patterns no real faults were seen.

**Before it came to me the customer had installed borg warner wires, and Autolite double platium plugs ** All plug gaps are correct and the ignition firing order is correct.

I have also scanned all the data stream values all appear to be with in spec KOEO TP2 voltage is around 1.4 . TP4 voltage was 4.02, KOER TP2 voltage was around a 1 volt.

So that being said I suspect and injector so what I did was I took my stethescope and pinpointed each injector all six injectors have a very blount noticable click to them as they are fired. I checked all of them three times with the stehescope.

My next step was to install a vacuum guage to check the engine vacuum, using a 4" Mac Tools gauge coming off of the plenum port and one of the EGR ports I had a very steady 19" of vacuum at a idle.

That being done I unhooked the EGR valve on it, it made no differnce in the way it idled still rough.

That being done I supsected a possible carbon issue, so I connected the vehicle to the MotoVac carbon clean system. I ran a 30 min cycle on the vehicle reving it up about every ten mins varying the rpms why it normally idled the rest of the time.

After that was done it still idled rough, I pulled all of the spark plugs, they, appeared to be a little black on the intake side which probaly came from the carbon cleaning I did to it before hand. The vehicle had not been driven since the MotoVac had been performed.

Does any one have any ideas on what could be wrong ? Any input is welcome.

I also performed Resetting the KAM after the intake gaskets were installed I unhooked the battery let it set for 10 mins, Alldata says 5 minmal, turned the headlights on and reconnected the battery.

It still idled rough mainly around 800-1200 rpm after that it clears up, if you drive it 35,45,55 or how ever fast it runs smooth as silk has plenty of power just a rough idle.

I could feel a lil bit of roughness in it around 10-20 mph its around the 1200 rpm mark then. Which I was just coasting along with my foot barely on the gas.

Did your datastream also give the long term and short term fuel trims? What were they at idle?

-Rod

Yes they did, orginally they the long term was around 2-5, and now after the reflash the short term is around -2-5 the long term is 0 the short term fluctates a lil bit at idle which is typical.

That was one of the first things I checked orginally and none of the numbers were not really high SFT or LFT.

What is a TSB? I have a rough idle on a '97 Sport and tried many things with no success. I'm foolish enough to attempt replacing the intake gaskets myself but I can't get the EGR tube out of the manifold. What's the trick? Any other tricks I should know about?

Ck the balancer that was what was wrong with that one the weight had came loose inside it on if you have a intake problem your fuel trims will be very high

A TSB is a Technical Service Bulletin. It is basically a white paper detailing a fix for a common problem. It is NOT a recall though and if your vehicle is out of warranty, the TSB service will not be performed without cost. It should just mean the diagnostic time is less to find the problem.

If the EGR tube you're trying to remove is the end that connects to the plastic intake manifold, it is just held in with basically an o-ring. Some wiggling and twisting should allow it to slide out. The part that will slide out is the dish that's approximately 1.5 inches in diameter.

-Rod