[KesslerR]

Buying a 1992 968 with 91K miles that had only been driven 1000 miles in the last 40 months I find that if it has not been run for a while it cranks for 4 to 5 seconds either cold or hot before starting.



If it stalls after running for a minute or so it starts right up again. The starting sounds are the normal starter motor cranking speed and the after about 4 seconds the cranking speed slowly increases until the engine is running at idle rpm. Many times if I do not add a little throttle it will stall again, but will start right up again.



It had a quarter of a tank of gas in it when I bought it and I did not think to ask the owner when he had last run the car or added gas.

I filled the tank with premium and have used most of a tank full on the highway and around town. I am not sure what to do next.



Several choices, the filter in the tank outlet, the fuel pump, the main fuel filter, the injectors, the pressure regulator. i do not have a pressure gauge to put on the fuel rail, but is that where I should be starting.



I am confused about jumpering the DME relay. i see the references to 3 pins not 2, 87, 87b and 30. Just tie them all together?

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[banditsc]

I'd dump some fuel injector cleaner in that tank, load it up good. I would also change out that fuel filter and the check valve at the bottom of the tank while your down there. Also take a look around the engine bay at all the hoses and wires, you could have a bad vacuum line or a bad wire connection somewhere.

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[SILVY968]

Agree. replace the fuel filter. Check the plugs. Check the battery voltage. Clean the <acronym title='mass air flow'>MAF</acronym> wire with special <acronym title='mass air flow'>MAF</acronym> cleaner ( do not start the car until dry!)

Brian

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[RS Barn]

Drive, drive drive.

I"m sure all posted is actually happening.

Fresh fuel, injector cleaner and mileage should inprove initial driving impressions.

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[KesslerR]

Thanks to all for the suggestions. Sounds like simple is better to start with.



Battery voltage is good. I plugged in my GPS which has voltage readout and watched while it cranked and started. Next is FI and <acronym title='mass air flow'>MAF</acronym> cleaner which I can get at the local autoparts.



I will get an new fuel filter from Porsche dealer here and get that in.

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[Ceenit]

WHen it comes to starting problems on any 968, I'd always start with a new DME relay. For $30 it can make the world of difference, and given how regularly they have issues, everyone should carry a spare in the glove box. After that, I'd do the fuel filter, additives, vacuum hoses, etc.

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[flash]

if you're changing the fuel filter, there is a check valve back there that is supposed to keep fuel in the rail when it's sitting - that may have gone south, causing you to have to fill that first before you can get fuel to the injectors

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[Chris Vais]

Once you get the car to the point where it starts and runs. I'd do a timing belt and balance shaft belt change as yours well past the 3 year or 30K miles rule.

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