- Location
- Lafayette, IN
Ok, I've got this somewhat narrowed down, here's what I know. Next 2 paragraphs are background, last one is the important details.
Picked up this 87 XJ a while back, it ran fine. I didn't have much time to work on it at that point, next time I went to drive it it wouldn't start. Figured out the fuel pump was bad (87s don't have the ballast resistor, it's easy to tell when the pump is running!). Changed fuel filter and then fuel pump, went through some self-induced wiring stupidity, figured out I had the pump wired backwards so I fixed that and everything was great. Had a little fuel leak around the return line O-ring, so I bought the *proper* kit and fixed it. It started, ran great, I moved it outside.
Again, didn't have much more time to work on it, I went to start it again recently and it would crank and crank but not fire. Eventually it would stumble like it wanted to start, but still nothing. I knew it was getting fuel fine before, so I made a bad assumption that it was ignition. I changed CPS with a new one (bought a while back, why not). Did all the diagnostics for TPS, sync signal generator (distributor cam sensor), ignition coil, etc. Everything checked out so I went back to looking at the fuel system.
The test port on the fuel rail always lets air out. I can turn the key, prime the pump, and hit the test port and get air. Turn it off and retry, more air. No matter what I do I'm getting air out of the test port. I don't have fuel in the vacuum line of the regulator, what else can I check to determine if it's the FPR or not? Otherwise what else am I looking for? Another bad O-ring letting in air? Cracked fuel line? I doubt there is a cracked fuel line inside the tank as it is a new pump, however I cannot find any fuel leaking out from any of the fuel lines or fitting though. Which makes me wonder if the pump is picking up air.
Thanks in advance for any help you can give me! :worship:
Picked up this 87 XJ a while back, it ran fine. I didn't have much time to work on it at that point, next time I went to drive it it wouldn't start. Figured out the fuel pump was bad (87s don't have the ballast resistor, it's easy to tell when the pump is running!). Changed fuel filter and then fuel pump, went through some self-induced wiring stupidity, figured out I had the pump wired backwards so I fixed that and everything was great. Had a little fuel leak around the return line O-ring, so I bought the *proper* kit and fixed it. It started, ran great, I moved it outside.
Again, didn't have much more time to work on it, I went to start it again recently and it would crank and crank but not fire. Eventually it would stumble like it wanted to start, but still nothing. I knew it was getting fuel fine before, so I made a bad assumption that it was ignition. I changed CPS with a new one (bought a while back, why not). Did all the diagnostics for TPS, sync signal generator (distributor cam sensor), ignition coil, etc. Everything checked out so I went back to looking at the fuel system.
The test port on the fuel rail always lets air out. I can turn the key, prime the pump, and hit the test port and get air. Turn it off and retry, more air. No matter what I do I'm getting air out of the test port. I don't have fuel in the vacuum line of the regulator, what else can I check to determine if it's the FPR or not? Otherwise what else am I looking for? Another bad O-ring letting in air? Cracked fuel line? I doubt there is a cracked fuel line inside the tank as it is a new pump, however I cannot find any fuel leaking out from any of the fuel lines or fitting though. Which makes me wonder if the pump is picking up air.
Thanks in advance for any help you can give me! :worship: