Body shake from engine (seemingly)

[ProfessorChaos]

First off I would like to think absolutely everyone for the Perfect info from experienced forum members. Have saved me at least $2000 in repairs so far. I'm in the U.S. Army and stationed in Germany have been in Europe 5 yrs. That aside:

I bought a 97 Ford Ex from a sloppy DIY. I've fixed alot of stuff so far includes:
A/C: Culprit; blend door actuator.
Headlights: Lamp outage module plus some other unknown (Had to run wire from module straight to headlight will "professionalize" later.
Addtionally all the sloppy wiring he did to put a system to include an XBOX 360 into the truck. But I digress ALOT!! Sorry.

Now I have another problem after ignition (3 minutes approx) the whole body of the vehicle seems to shake or pulse with the engine which seems to have irregular revs. More a sputter maybe. Seems like fuel intake so I initially thought it might be the fuel filter, so I replaced at an Auto Skill Center. PITA!

No fix. I've ordered new spark plugs because I do not know when they were replaced (considering the quality of other work not likely) to maybe fix the issue. Waiting on mail delivery there. But I have a sneaking suspicion that is not the sole culprit. Add to that I already have 8.5 wires that came w/the truck for a tune-up. The dude ordered the wrong ones (spark plugs) Pre-gapped Bosch Platinum. I had to order the correct gap.

Add to that a seriously bad gas mileage. I mean bad! Today I went from 1/4 tank about 1/8 of tank. I drove a 1/2 click and idled 10 min tops to fix my stereo. I think I have probs. LOL and when I bought it at full tank I've driven maybe 50 Miles. My info center went from 100% oil life to 14% And I seem to have a lag from gas pedal to tires in that I have to press more than usual to get a response and when it does it lurches like a manual that's revved high upon release. Doesn't seem to be transmission because it shift and changes gears smoothly. I know this is alot of info but I'm trying to fix it all myself. I love DIY.

I have read and learned wiring diagram manuals brakes and for leisure I read the Haynes/Chilton's manuals I own for the Ex like a novel. Please some input.

 

[JDraper]

Hmmm...could be a bad fuel pressure regulator. If they go bad, fuel gets sucked into the vacuum system giving poor mileage and rough running. If enough fuel gets in, it could also dilute the oil.

 

[ProfessorChaos]

How do I diagnose such thing? Where to begin?

 

[JDraper]

Pull the vacuum line off the fuel pressure regulator. If there's fuel in the vacuum line, then the fpr needs to be replaced.

 

[ProfessorChaos]

Rough runnning

Alright I figured out why it was running so roughly and also feel foolish. The guy I bought my Ex from had bought new plugs and wires (the kind you have to assemble) well apparently he had installed two new plugs and one wire. I assume because of the difficulty he quit. Well the one wire he assembled was completely F'ing wrong. So I replaced all plugs and wires today PITA! The body shake is gone now. And most like now that I have 8 of 8 cylinders firing my fuel economy will improve.

Now to the next. While digging around in their I unplugged the vacuum line from the FPR and noticed no fuel or smell. However when I rev it is sluggish and at 1700 2700 RPMs it still shakes terribly. Maybe gummed injectors? Thoughts?