Recently my 2000 TJ 4.0 started experiencing mild starting issues. It seems to crank fine but only starts after I stop the first attempt and try again. For background, two years ago I replaced crankshaft position sensor and fuel pump. one year ago I replaced the ignition. Any thoughts on why I am experiencing this and how to resolve it. I've read through the numerous threads on starting issues but can't seem to identify my issue.
Jeep cranks but only starts on second attempt
- Thread starter drcomf22
- Start date
Sounds like a failed check valve in the fuel pump assembly. Which fuel pump assembly did you install?
Try cycling the key on and off two or three times for a second or two each and then try to start it. It if starts right up, it’s likely the check valve.
Try cycling the key on and off two or three times for a second or two each and then try to start it. It if starts right up, it’s likely the check valve.
After you try cycling like @NashvilleTJ suggested I'd look at the ignition switch. I've heard that if the Jeep starts just when you let off pressure from the start position it can be a bad ignition switch. The Jeep basically starts just as you let off the key if that makes sense. It's a different deal than fuel pressure which cycling the key isolates. Just another option to consider.
Thank you! I'll give that a try tomorrow. I bought the Delphi FG1353 fuel pump because i couldn't seem to find the Bosch..
OK...I think this may be my problem. I cycled the key like 8 times then tried starting. There was a very slight hesitation but it started. Going to test agin later today. If this is my issue I assume this means i need to buy an entire new fuel pump assembly. Correct?
That's the best bet.
You don't need to cycle it 8 times. 2 to 3 times for 2-3 seconds each. The deal is that the check valve in the pump assembly keeps the fuel in the line from draining back into the tank when the engine is not running. If the check valve is nor functioning correctly, fuel drains back into the tank when the engine in not running, and then there is no fuel at the fuel rail and the injectors to start the engine. When you turn on the key, it takes a little time for the fuel pump to get fuel back up to the engine. When you turn the key to the "run" position the fuel pump operates - but only for three seconds if the engine is not running. That's the reason you need to cycle the key a few times.
Thank you for the advice. This is 100% my problem. Frustrating since I bought the Delphi pump just two years ago. I’ll get a new one. Cheers!!
This is a very common problem. If these are your symptoms then the check valve has failed. If you can get a Bosch pump do so.
If your car has trouble starting after it's been sitting, it might be because the fuel system isn't keeping enough pressure. It could be from a leaky fuel injector, a bad fuel pressure regulator, or issues with the check valve in the fuel pump. To figure out if that's the problem, check the fuel pressure with a gauge before you start the car in the morning and see if it holds pressure when it's off.
The check valve is in the fuel pressure regulator, which is separate from the pump. I believe it sits on top of the tank.
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