Fuel 1992 351w Swap Fuel Pressure Issue/problems - Please Help!

Hey Guys,

I'm relatively new here and to the Fox-body scene.. I had the chance to scoop up a really nice 92 that had been 351w Swapped (Still has EFI). Since acquiring the car I'm noticing a few things that aren't right. The first and right now - most important - the Fuel Pressure and subsequent issues b/c of it. Let me explain..

The car has a no-name ADJ FPR on it with a built in gauge. The gauge reads 90-95PSI !!!. There is also a HEAVY gas odor in the Oil. I suspect the absurd pressure is washing fuel down the cylinder walls and thus creating the gassy oil. Here are some of the things I've "tried"..

- Checked vacuum - There appears to be vacuum at the FPR as when the line is removed the FPR's gauge moves (increases pressure) about 4lbs.
- Manually sucked on the vacuum hose to pull up the diaphragm in the FPR - the gauge again moves - albeit ever so slightly - 4lbs ish..It appers to still be air-tight
-Turned "out" the screw to lower the pressure - best i could get it to was about 75lbs before the screw fell out- At that point the car would barely idle.
-Tried a base idle reset (youtube video) at 75lbs and wasnt able to stabilize the idle at all..
-Reverted back to 90+/-lbs and was able to get the idle back under control but at the cost of increasing the Fuel Pressure again..

What i plan to do next:
-Test the Shrader valve with another Gauge (tomorrow)- Im expecting no changes here given the gassy Oil issue..
-Disconnect the Return line and see if the pressure releases (indicating a potential clog back to the tank)..Kind of hoping this isnt the issue..
-Replace the ADJ FPR w/ a stock one.. Easiest and cheapest fix..

What do you guys think? Am i missing anything, anyone have a similar experience?

Lastly -- Im in Pittsburgh- just north of it but that doesn't matter.. what i am looking for is anyone (Shops, people, cats, dogs...etc) who are well versed in these cars and their nuances .. That i could potentially go to in these types of scenarios.. Any leads whatsoever based on my location would be EXTREMELY helpful.

Thanks!
Paul

got some more information tonight..
- Checked the Gauge when i got home.. it was at 62lbs..Pushed in the shrader valve and ...nothing.. no pressure/gas at all..
-Primed the system, jumped to 92 on the gauge, checked the valve again, this time there was gas/pressure..
-ran the motor for 2-3 minutes, shut if off completely and then re-primed the lines (turned the key to ON w/o starting)
-Checked 3 hours later.. Pressure dropped to about 70lb's

From this information, i think its safe to say that i have a leaky injector or injectors.. Do you guys agree?

next steps- pull the rails up, take all the injectors out of the manifold, reattach to rail and re-pressurize. Once pressurized ill wain to see which are leaking unless you guys know of a better way??

Thanks!
Paul

Steel1 said:

Fuel pressure will drop over a period of a few hours, I wouldn't condemn the injectors just yet.
I would continue to do fuel system check to verify cause, just fyi I run a stock regulator on my 393w.

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Thanks Steel1 - Since i clearly have a Gauge issue (Reading 60lbs w/ no pressure in the line) - ill obviously retest with a secondary gauge to verify proper pressure etc. Assuming pressure is good, how many other ways could gas get into the Oil besides a leaking/failing injector? I will replace the Adj FPR w/ a stock one for good measure next.

General karthief said:

Get a repair manual,

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Great idea - and i will for sure. However i don't have one right now and i have a right now kind of problem.

Thanks General- i appreciate the urgency you're providing. It helps to know the severity of these issues which i'm learning here -REAL quick!

Anyway, Oil was changed about 1 weeks ago. (by the previous owner) - there is maybe 2 hours of total run time on the car while in my possession. He claimed he changed the plugs/oil/filter 2 days before i bought the car. Visual inspection of the Oil and Filter would lend me to believe that to be true.

I've had it since Thursday. It has about 2 hours of total running time on this batch of oil (obviously an estimate). When it was test driven, and even driven after the sale it didint smoke at all.

I have new oil and filter in the back seat of my daily - will be replacing it over the weekend.