5000S Wierd Startup Problem

[johnnyg]

No guarantee that the car will start. I can start it (maybe) and it runs fine, turn it off and it will crank (with no hint of starting) but will not start. Car has only been in the driveway as I just started "rejuvenating" it. I have a feeling this is why the car was originally sold. Coil, Hall Sensor or ICU? Don't know but would appreciate any feedback I can get! It's getting spark and gas, checked the coil for spec and it's okay.

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[audidriver88]

my 5000 did this sort of thing. it does it because sometimes the fuel pump wont prime. its a definate problem on HOT days. check the fuel pump fuse. if you use cheep gas that could be the problem, the fuel pump doesnt like it! if it wont start, keep turning the key off, then to the on position but dont start it untill you hear the fuel pump prime. you should hear a wining coming from your back seat and youll know its working.

[Lyman_T]

If you jump it, will it start every time? That can also tell you something.

[audidriver88]

if jumping it starts it then you have a bad battery or alternater

[johnnyg]

Thanks for the reply. I'll listen and see if the pump is priming. I've also pulled and tested the cold start valve, and it works fine. This is driving me nuts. Nothing worse than not knowing if it's going to start the next time you get in it. Started effortlessly for 5 consecutive days, on the 6th, cranked over but wouldn't start. Can go out the next day and it's fine again. When it fails, there is a quick mini backfire type noise from under the hood, and that's it. This has nothing to do with jump starting, that is not part of the problem. It gives the symptoms of a fuel issue, either some type of instant starvation or the like.