1987wranglerowner

Moses. For you and any others following the thread, I have had to put the problem on the back burner lately. Hope to get back on it this week. Thanks for the advice. I will post future work and results.

Hi Speed. When I replaced the fuel pump the screen was cleaned and checked as well as the tank.

Good Morning. I guess I have not mentioned it but before I contacted you the first time I had checked the resistance on the manifold temperature sensor and the water temperature sensor. I also removed, cleaned the crank position sensor and tested the resistance. Since your last response I have ran a ground from the fuel pump ground wire at the rear pigtail and grounded it to the frame at the rear, no change. I ran another hot wire from the battery thru a switch to the rear orange fuel pump wire to make sure the pump was never losing power, no change. Even thou the plugs are not fouling, is there anything inside the throttle body that would fail and bleed off fuel pressure under high demand (load)? Is there any gaskets or seals that could go bad and bleed fuel pressure in the throttle body?

Thanks for the response. This morning I cranked it up and pinched the return fuel line under the TB and watched the fuel pressure rise multiple times. I think that tells me there is no restriction on the fuel return line. Then i removed the gas cap and drove it. It still fails. I think that tell me the tank venting is not the problem. I have looked at all the EVAP lines as well as other vacuum lines. Don't see any problems but. If you don't think my return line or gas cap test is effective, please tell me. I keep going back to the thought that its in the electronic fuel injection, something telling the injector to stop delivering fuel but the fuel pressure gauge says its mechanical fuel delivery unless some other electronic device on the TB can stop the mechanical fuel flow.

HELP!!! I have a 87 wrangler, 2.5. When you test drive it, under acceleration, it gets slower and slower and starts to back fire thru the exhaust. After installing a fuel gauge to the TBI test port and running it inside to the dash, I can ride down the road, accelerate and watch the pressure drop from 15 lbs down to nothing. Based on these findings I replaced the fuel pump, filter, regulator diaphragm and adjusted. I still have the same problem. I ran a wire back to the orange fuel pump wire and tied it in there, connected it to a volt meter and drove the vehicle to see if it was loosing voltage to the fuel pump for any reason. It is not. It maintains 13 to 14 volts at the fuel pump but the fuel pressure will drop while watching both the gauge and meter. What else can stop fuel flow to the injector. I know the injector is part of and is controlled by the ecu system but this seems to be a lack of fuel pressure and seems as thou you would have to cut voltage to the fuel pump to cause my problem, but that is not happening per my testing. By the way, this jeep cranks fine cold or hot, will sit in the garage under acceleration and not miss a beat. Problem is only under a load while driving. HELP PLEASE