My name is ***** *****. I have a 2000 Grand Cherokee, 4.7, auto, 143,000 miles. The engine dies occasionally, when it dies the fuel pump
does not run. I rigged a jumper to power the fuel pump when the engine died. the next time it died I used the jumper. I could hear the fuel pump run, engine turns over, no start. apparently the problem shuts off fuel pump and injectors (spark?). After cool-down the engine starts immediately and runs perfectly. It seems to show the problem after an hour or so of run time. the cool-down can be 5 to 45 minutes. It seems to take longer to cool down each time it dies.
JA: Thanks. Can you give me any more details about your issue?
Customer: yes, I have replaced every relay related to engine run or fuel, have swapped out every fuse related. I rigged a test light inside, so I can tell if the fuel pump looses power, It does loose power to the fuel pump. I have taken loose every ground (I think) to ck for connection. I replaced the ECM with a known good from another matching Grand Cherokee. No codes set, the "ck eng" light does not come on. I did replace the crank sensor about a year ago, engine displayed a very different problem with that, with a "ck eng" light.
JA: OK got it. Last thing — Jeep Mechanics generally expect a deposit of about $18 to help with your type of question (you only pay if satisfied). Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.