A month or two ago, I wanted to move Ike around the driveway, only he was having none of it. He would crank just fine, but nothing else…as if he’d run out of gas. He was low, so I dumped 5 old gallons in, but it didn’t change his mood. Finally listened at key turn, but no fuel pump sound. Whatever, I manually pushed him to the other side of the driveway.
Finally decided to get his old ass moving. Bought a new pump and strainer, thinking that even if they weren’t bad, it was still a good idea. I had swapped the original 1 hole injectors with 4 hole ones from later models, so I figured a pump with a bit more flow would help.
Roll under and inspect the situation. First, I noticed something that was completely unrelated, but completely related to another bad issue I was having. Massive driveline vibration. As I dragged my fat ass under the jeep, I grabbed the driveshalf. It moved. Laterally. That’s not a good sign. Turns out that all 4 of the u-joint bolts to the rear diff yolk were loose. Now whether I didn’t tighten them or a failing u-joint caused them to loosen, who knows. The joint seemed alright, so I regreased the caps and bolted it back up. This time with loctite.
As I had seen before, the pump is one of the easiest to get to since they actually designed it so that you didn’t have to drop the tank or cut a hole in the trunk to access. Brilliant! And since this isn’t the rust-belt, I was able to easily rotate the retainer ring and pop it off. As I pulled the whole pump and sensor assembly out, the fuel line running out to the filter basically disintegrated. The outer shell completely failed when bent at all. But otherwise, it came right out.
Swapping in the new pump went about as well as expected. The new bottom isolator mount was completely wrong so I had to use the old one. The supplied hose was either too long or too short, depending on which hose you were replacing. Both the pump and the strainer came with retainer washers, only 1 of which barely fit. At least the electrical connector fit, so I slapped it back together and threw it back in the tank.
Then I replaced the fuel hose that had fallen apart and the inline fuel filter, which they now just give you a generic one that fits the hose size. Your brackets be damned. Zip tie it all up, groan as I roll out and up, and hit the key.
Brrrrrr…click!
Sweet, that works. But the battery is tired, so I hook it up to the charger and try again. I get good cranks, but only hear the pump kick when I turn the key on from the off position. Again, it sounds like it had no fuel.
Previously, I had checked and swapped every fuse and relay in the fuel and ignition systems. I even check for spark with a timing light to make sure the distributor was firing at the right time. Assuming that hadn’t changed, I struggled to think what else it could be. It definitely seemed like an electrical problem.
One really weird thing I’d run into was that I occasionally would get injector misfires, but playing with the engine harness would cause it to work. Ok, so I start grabbing wires and wiggling them. This is my engineering education being fully utilized!
Well, shit. When I grabbed one end of the injector harness, I could hear a solenoid click and the fuel pump kick on briefly. So, that’s something. Wiggle, wiggle, trying to figure out where the fuck is the broken wire. I start cutting off electrical tape, but it’s so old and brittle it just crumbled, making it slow and swear inducing. After removing about 9 inches of plastic conduit and tape, working a section from both ends…it is right in the middle, of course. And it’s plain as day as soon as the tape is off.
There are 6 of what I assume are ground wires connected to a giant sphere of solder…with the one leg that goes to the main harness loose. When they touch, click and happy pump noises. The wires just broke over years of use. It really is the dumbest way to do that I can think of. Let’s hide a connection halfway through a harness leg. One that is susceptible to failure when flexed. And then wrap it up and put conduit on the outside. Brilliant! Dumb fucks.
So I strip the wire and add to the solder glob. Hit the key to make sure it kicks on the pump and then wrap it all up. One last check of the fuel system and then hit the key for real.
Vroom! Well, I have to hold the pedal down a bit, but it fires and runs. Suck it Chrysler dicks! Make sure I have a wallet and head off to gas station. But once I hit the main road and accelerate, Ike is still pissy. Slow to shift, and when the revs are high, the oil pressure spikes and I start to hear ticking. Damn it. Turn around and head back. Jump in the RX7, run down to gas it and a 5 gallon tank up, and get back. See how easy that was Ike?
I add some fuel cleaner and gas to the tank. Then dump some Marvel Mystery Oil into the crankcase and fire it back up. Ike fires and runs. Let it idle for 15 minutes and no issues.
I get brave and go for a test drive. Through our little town at 45mph, he behaves pretty well. If the revs go about 4k rpm, I can hear the tapping again. It sounds kinda like pre-ignition. Well, 4k isn’t where you should run this motor anyway. The more I drive, the more he seems to calm down, shifts easier. Confidence growing, I head up the hill on a scenic drive. When pushed hard, it will still spike the oil pressure and ping, but cruises ok.
Coming down, I try high and low revs to try to work things loose. I get down to the main road and wait for a hole in traffic. Man, it’s running smooth. So smooth it sounds like it’s off. Oh shit. Yup. Just died at the stop sign. No drama, just revs to 0.
Hit the key. Back to just cranking only. Now, we’ve been here before. When he is run a while and gets hot, he just needs a break. I know the feeling. Happened to Kim once at a gas station. So, I push him to the side of the road and wait. 5 minutes…nope. 10? Nope. Somewhere before 20, something kicks and fires. It was a good thing I brought a spare battery and jumper cables because the installed battery isn’t really holding a charge for long.
I get back home and park it, but let it run for an additional 15 minutes. Sounds great, idles smooth. Like a happy jeep.
I turn it off. Just for fun, I hit the key again.
Just cranks. No fire.
Fucking mopar.
