Hello. Please see my Intro if you care to!

1984 4+3 w/Crossfire

I purchased this car in August. It didn’t run great when I picked it up. An older man had bought it who was into 50s Mercury’s. The problems of this car were obviously too much for him. He replaced the battery and the fuel sender. Then it sat for 2 years. Prior to this it was owned by a frat boy hooligan.

The car would start off stronger for a few minutes following ignition. I bumped into a guy that claimed he knew the issue. He ended up replacing the 2” section of hose in the fuel tank, , fuel filter, and the coil/cap/rotor because the coil had burned a hole down through the cap. This greatly improved the driveablity. But it doesn’t end there.

I can get a good 5,10, or 20 minutes of strong power depending on how hard I keep pushing the engine. Once the car has just been cruising for a couple minutes, 55 or whatever in OD, it will no longer pull hard. It skips, misses, jumps, you name it. Same thing if you drive hard then slow down through town. I pull over and turn it off. Often in less than a minute, fire it back up, rip roaring ready to go. And the cycle continues.

I have replaced the following-
igntion cap/rotor/coil AC Delco
all 8 plugs AC Delco
ignition module Pertronix Flame Thrower
Engine coolant temp sensor Pep Boys
Map Sensor AC Delco
Map sensor vacuum line Napa
TBI rebuild kit AC Delco
recalibrated the TPS it swung fine on a meter

The only item that even remotely made a difference was the new coolant sensor. Now instead of a high idle when coming to a stop it will stall out when up to operating temp. I am very bothered a spent several hours rebuilding the TB units to yield 0 improvements. I hope someone can help with what I should do next.

 

Check the fuel pressure while its acting up.

 

Okay. Can you tell me where to tap in? I’m not seeing a port around the lines. Ecklers has a nice gauge I’d like to put in that comes with some screw in fittings I thought that’d be nice to have.

 

You cap hook into the fuel filter lines, they're rubber hoses with clamps, so use a universal efi pressure tester.

 

So before I spent the money to check fuel pressure, I decided to check something that was already checked, as it didn't cost me anything to check it.

I pulled the fuel sender out of the tank. I got a new sock filter from NAPA just for funsies. The old sock looked like a used tobacco chew pouch. Someone had replaced the sender I was told. Someone put a Carquest pump in there. Then the mechanic I took it to had replaced that 2" section of hose. Somehow no one thought it was necessary to replace that sock filter. Problem solved! I've been chasing this down for 2 months. I'm disappointed I had to check an area a mechanic told me was All Set. But with 13 years of working on cars I should know better by now. If you want something done right, do it yourself. $13 fix.


I hope I can get another good 3 weeks of fall cruising before it gets put away!