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I just recently bought an 88 Comanche that is a really big Frankenstein with a 91 Cherokee. I went to fill up the tank and as usual in jeeps, the pump wanted to stop every 5 seconds. Tried going slowly but nothing worked. It took me 10 minutes to get 2 dollars in, and when I did the gas started to overflow. That is where my bigger issue is... there is barely any gas in the tank and it won’t fill up? Any help? THANKS!

Hey guys so as some of you have checked out my build thread, I have an '06 engine of a TJ on my MJ, and the PO either did not want to struggle with adapting and finding stuff for keeping the HO intake manifold, or (what I think happened) he probably bought a wrecked/salvaged TJ and the original manifold was probably cracked so he just installed the old renix on it to get it running. Anyways, I already got me a new set of Headers, and the HO intake manifold and of-course bolted right on, but the only doubt I have is that on the old Renix fuel rails it had what I think is a Fuel Pressure Regulator, and a Return Line? Anyways when I got the new fuel rail and Injectors ( :brows: score! for $19.00) at the JY it only has one port, or entry instead of two, as the old Renix fuel rails do. So Basically my question is, do both fuel lines that come from the gas tank spit out fuel? if that was the case could I just cancel out one? or What should I do? Anyways those are my doubts, any Help is Greatly Appreciated! PS: I know I've been slacking a lot on wrenching on my truck and posting on my thread so please forgive me and give me $#!& about it so I can get back at it my friends here haven't stopped but Ill take any sort of motivation over no motivation at all! haha Oh and don't feel bad for talking smack! hahaha :yes:

I’ve just finished reassembling my MJ after a solid year of partial restoration and am ready to get it inspected. When cranking, all I get is – no fuel is being injected. After probably a minute total of cranking over several hours, the cylinders and spark plugs have no traces of fuel. It provided a healthy pop when starting fluid was sprayed. First thing I did was pull the feed hose (feed and return are -6AN Aeroquip) from the ’94 rail and verify that it was providing sufficient supply when priming at key-on. All seems good. The CPS (new, so untested) appears to be functional as the spark plugs fire consistently. Injectors are reman/matched Bosch units, though I’ve also tried the old Bendix units since they’re handy. When checked, all of both sets provided impedances that should be accepted by the ECU. Although my multimeter can’t get a reading from the short pulse width provided by the ECU, it does display quick nonzero voltages when probing the injector pigtails while cranking. Fuel pump seems to be functional – previous owner installed it in September 2011 (~1500mi) and all I did was pull it to replace O-ring and lock ring when I installed the new rollover valves/grommets and new injection hose & clamps. It primes the system nicely at key-on. All underhood electrical grounds are new and I cleaned/regreased all just in case. I also cleaned out the bulkhead connector. All electrical systems work apart from the interior lights (may need to finish some underdash wiring) and the radio (which illuminates but doesn’t turn on – probably also a minor issue). All exterior lights, chimes/buzzers, and non-mechanical gauges function correctly. All sensors are new (though I wish I'd left the old ones in for the time being). This leaves me completely puzzled, but with a few possibilities. Bad injector ground(s). I can’t imagine that all of the signal wires have failed, though (if I remember correctly) the 1990 electrical manual refers to each injector grounding independently to the ECU. The 1987 diagrams show a common ground – I thought these were identical systems, but I guess the transition away from the C101 connector changed things. Zero/insufficient fuel pressure, possibly due to failed FPR (also new/untested), though I thought it would simply fail at the 31psi under-vacuum position. When bleeding the Schrader valve on the rail, it always has an air pocket that reappears very quickly and the valve never produces a strong spray, so I'm suspicious that the FPR is just looping fuel back through to the tank. But wouldn't the injectors do something, even under low rail pressure? Fried ECU. I originally had the battery ground going to the block, though this changed when we noticed that the ’87 Renix troubleshooting manual clearly shows the battery grounded to the starter. Doing this resulted in a very hot ground and a clicking starter (why it’s different from the manual and why the starter isn’t grounding through the block is beyond me). Returning the ground to the block fixed the issue and it cranks smoothly, but would the ECU be susceptible to damage with the bad ground? My next step is to put a gauge on the fuel rail and confirm that it’s pressurized properly. If that isn’t the case, I’ll swap out the Renix ECU for the Mopar-flashed TSB ECU, but is there anything else I’m missing? Any well-known Renix issues that could be behind this? Thanks! Bob a pre-disassembly shot...