Popping, arcing sound, smoking. Top of motor wet.

[Hank]

Came back from lunch and just about the shut of explorer when a number of fast loud pops, hisses and smoke began. Could be best described as a loud arc welder sound.

No funny gauge behavior, quickly opened hood and saw smoke coming from the top drivers side of the motor underneath the intake. Killed engine and noticed that top right, drivers side, of motor, from front of t-stat housing back 2 injectors along with front of drivers side is wet. HOWEVER it is not coolant, fuel or engine oil. Very thin and light colored. Almost like mineral oil. Enough to pool a little around the area of the front two injectors.

Thought is was A/C compressor but A/C is still working, not making noise and seems cold. Tried to feel around the compressor for leak but could not really see or feel any. Motor was hot from driving.

On restart this did not continue. Any ideas appreciated.

 

[Hank]

Well I've moved all my gear and personal items to the back cargo area and am going to drive it home.

If it burns up, guess I'll go get a new Toyota FJ.

 

[Papa]

Sounds like brake oil is it possible there is moisture is the brake system?

 

[Hank]

Nope, brake system is new including RABS, master and superlift lines. Also tasted the fluid and it is not brake either. Also no brake lines run that direction.

Made it home with no problems, drove the living daylights out of it on the way home. WOT, hard starts hard stops. no problem...

Ripped the alternator out and moved the A/C compressor aside to see what is going on. Found nothing.. Even looked for cat hair in case I sucked up a cat.. nothing... Alternator brushes looked good. Replaced those last year also.

While I was in there I cleaned up all the various sensors and checked wiring harneses. Really found nothing...

Started it up and let it run for an hour, did not happen again..

Baffled....

 

[trucku]

How about your power steering fluid? maybe some oveflow or shot out?
Also if your coolant resevior exceeds 16 pounds of pressure won't it vent and make a hiss sound? Maybe the shut down made it experience some sudden pressure rise and then it vented. Maybe couple of things happened together.

Good Luck in finding the problem

 

[Hank]

Nope those are fine also. Can't be cooland as I have leak dye in the system. Stuff shows up like radioactive waste.

Found this on a news group..

Found this on a newsgroup. Possible flakey fuel pressure regulator?? No blown vac lines though..

I bought a 1994 Explorer in July 96. That move is on my top 5 list for the
dumbest mistakes I have made. At 36100 Miles (just out of warranty, go
figure) the fuel pump went. At 41000 and on a short road trip, the engine
blew a vacuum hose. And again and again another vacuum hose. Needless to
say the check engine light came on.I got to a dealership and they diagnosed
the problem and said that it was a mass air flow sensor and MAP sensor. I
left after the repair and 15 miles later the same hing happened.I went back
to the dealer and well , they diagnosed again. This time someone pulled
their head out of their ass and figured out that it was back pressure in
the exhaust cause of a bad catalyctic converter. The converter replaced
under emissions warranty and me on my way. 350 miles later the same popping
blowing up og the vacuum hoses starts again. Now I am really disgusted.
$20,000 for this crap!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I went back to ford with all my recepits and all my ANGER and let them have
it. They were totally puzzled. Finally someone said that the Ford Explorer
has a weird and un-predictable fuel pressure regulator. It was not showing
on the scope but they replaced it anyway and 3000 miles later?
Hallelujah!! It worked. No more popping vacuum hoses. But another fuel pump
is gone.

 

[Papa]

HOWEVER it is not coolant, fuel or engine oil. Very thin and light colored. Almost like mineral oil. Enough to pool a little around the area of the front two injectors.
On restart this did not continue. Any ideas appreciated.

This is beginning to sound foreign to the engine compartment, I feel for you.

 

[Hank]

I did some more explorer popping searching and am going to replace the fuel pressure regulator this weekend. Heck it is 15 years old and I have had other unresolved engine issues with no error codes in the past.

Will probably replace the original fuel filter also..

 

[Hank]

Going to chalk this one up to a bad pressure regulator. Still no clue on what the fluid on the intake was.

Idles a little better, too soon to tell about gas mileage improvement. Tasted a little gas in the vacuum port on the regulator.