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TomiK

No power/signal to fuel pump relay

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Hi,

 

2001, 2.7  Boxster will not start after being in garage for the winter. So far we have been able to find out that the relay is not connecting the fuel pump when cranking. When jumping the relay, the pump is running. Actually after this test engine will run for 1 to 2 sec, I guess with the fuel pumped during ""jump test". So, spark is there but no fuel.

 

We did check the fuses C1 and C4. They were ok. The fuel pump relay is new, like the battery. We did measure the "signal slots from ECU" at the fuel pump relay, but did not get any reading when cranking. So it looks like ECU is not sending anything to fuel pump relay. Some say it could be crank shaft position censor. Right, but why the engine did produce spark if censor is dead? Any great ideas how to proceed? :helpsmilie:

Thanks, Tomi

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Is it possible the wiring harness has rodent damage ?

The CPS is a know trouble maker and a replacement is not expensive. Did the rev counter needle bounce when you cranked? 

If the car was damp in storage maybe the ignition switch contacts corroded? Another trouble maker that is inexpensive.

I know it is silly to throw parts at it but the diagnostics have filed to help you.

BTW was your car assembled by Valmet in Uusikaupunki ? 

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You may want to try e-gas recalibration first since it's easy and free. Do you have Durametric?

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On 4/17/2019 at 6:25 AM, Schnell Gelb said:

Is it possible the wiring harness has rodent damage ?

The CPS is a know trouble maker and a replacement is not expensive. Did the rev counter needle bounce when you cranked? 

If the car was damp in storage maybe the ignition switch contacts corroded? Another trouble maker that is inexpensive.

I know it is silly to throw parts at it but the diagnostics have filed to help you.

BTW was your car assembled by Valmet in Uusikaupunki ? 

Hi, the car was in a heated garage in a room temperature. So it is completely dry. We did, however, clean the floor mats with wet carpet cleaner. That thing has strong vacuum and do not leave the carpets really wet. No sings of rodent.

 

When cranking rev counter rose to maybe 100 rpm.

 

I guess my car was build in Germany - but not really studied the case

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On 4/17/2019 at 7:56 AM, Ahsai said:

You may want to try e-gas recalibration first since it's easy and free. Do you have Durametric?

No, don't have Durametric or any other tester. What is e-gas?

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I would recommend doing the e-gas recalibration first, then verify fuel pressure. Note it's normal the fuel pump only turns on for about 1 second to prime the system at cranking. The fuel pump will keep running only if the engine fires up. That's a trivial safety feature.

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