I posted on another site and have recieved a lot of help but my problem still exists. I wanted to post a summary of that post and see if anyone here had any ideas as to what my problem could be. Anyway I'll give you a step by step of what I've done and the results. My car is an 87 coupe w/ 150k miles.

3 months ago my fuel pump went bad and I replaced it with a Walbro 255lph pump. When I took the old pump out, the electrical connection into the pump appeared to be slightly melted but I shrugged it off since it was the original 20 year old pump. Since the connector was melted I had to splice the plug-n-play adapter for the walbro pump into the factory wiring. Everything was securely soldered. I also replaced the fuel pump relay at the same time. Car started and drove fine.

300 miles later my car started acting up again. It would crank when cold and run fine until it warmed up then slowly drop in rpm until it died. Figured the coil was getting hot, replaced the cap, rotor, coil, plugs, and wires and still had the same problem.

First thing I did was check fuel pressure, found 25-35 psi upon cranking cold. It maintainedthat pressureuntil it was warmed up. I could watch the needle on the fuel pressure gauge slowley drop all the way to 0 and die.
[ul][*]Replaced fuelfilter. No change.[*]Replaced fuel pressure regulator. No change.[*]Pulled the sending unitout to check installation, which checked ok. However, I noticed that the insulation where I spliced the wires appeared to have gotten hot and turned brown likeit had melted.[*]Figured heat = resistance and ran a ground cable from the top of the sending unit to the frame to make sure it was grounded. No change, however my interior lights got considerably brighter.[*]Found service bulletin that calls for the elimination of the fuel pump "pulsator". Went to the dealer and got the parts which are basically a 2" piece of fuel line and 2 plastic clamps. Pulled sending unit AGAIN, installed said parts. No change.[*]Searched engine bay for anything amiss. Found a split vacuum line that runs from the fuel tank to the evap cannister. Figured it was irrelevent to my problem but fixed it anyway. Low and behold something changed, cranked the car and the pressure goes to 30psi and maintains it as long as I let the car run. Never dies.[*]Pinched fuel return line to tank and the fuel pressure raises to around 40-45 psi, but drops back down to 30psi as soon as I release pressure on the line.[/ul]
I can drive the car but it just has no get up and go, assumably, from low fuel pressure. My next step is to chalk it up to a bad fuel pump and buy another. Any ideas or suggestions on what to try before I drop another $100?

Thanks, Brian

 

Need to check your body grounds if the lights got brighter. A bad ground or grounding through another source will increase your current flow to the fuel pump and possibly causing your melted connector problem. Make sure the engine is grounded to the frame in addition to the battery.