Porsche Boxster No fuel or injector pulse

bagster · 10-04-2013, 11:43 AM

I have a 2002 Boxster that has no fuel or injector pulse. I have jumped the fuel pump and it runs and has pressure but still no start. Car turns over and starts with starter fluid. I have replaced my cam sensors and crank sensor. had the DME rebuilt bu ecu doctors , still no start. im looking at a large tree over the car and sharpening my chain saw.....

jwgn777 · jwgn777's Garage

Where did you jump the fuel pump to make the pump run? And you had the required pressure read on a fuel gage that was attach to the fuel rail?

bagster · 10-05-2013, 12:50 AM

It was jumped at the fuel relay under the dash. I don't have a fuel pressure guage but having removed the line after running it there was tons of pressure there. injectors checked with a noidlight and no pulse.

jwgn777 · jwgn777's Garage

Check your MFI-DI relay in the rear of your vehicle left side under the trim cover. Relay support Position 1. You are not getting power to you fuel pump relay I think according to what you telling me. And I assumed you check the fuel pump fuse.(That fuse is just for the pump not the trigger for the fuel relay.) Despite the fuel you see coming out of the line when you jumped the terminal, you need a fuel pressure gage to be accurate.

jwgn777 · jwgn777's Garage

[COLOR="Blue"] And make sure all the fuses are checked. I can't remember but i think the MFI relay is powered through a maxi fuse in the distribution center. Don't take you chain saw out yet!/COLOR]

bagster · 10-05-2013, 11:58 AM

I did check the relays swapped them around and cleaned and tested the points. Also the fuse under the dash is good. The relays clicks and switches off in the rear. then does it again in a few seconds. Ive been swapping the engine harness today should be done by tomorrow. the tech guy at ecudoctor seems to think it could be a short in the harness. if that's a nogo im going under the drivers seat and tracing the wires back to the motor from the immobilizer. something smells burnt under there. ()immobilizer tested good. had it checked also) thanks for the help I really appreciate it.

bagster · 10-05-2013, 12:00 PM

Also if I was getting some fuel pressure I would get a partial start? i'm getting nothing.

jwgn777 · jwgn777's Garage

Quote:

Originally Posted by bagster

Also if I was getting some fuel pressure I would get a partial start? i'm getting nothing.

You had said that you did not get a test pulse(light) at the injectors. if that is still the case then it won't start.Now it would only kick over if you introduce some fuel through the throttle body.

bagster · 10-06-2013, 11:00 AM

That's correct it will diesel start when I spray into the throttle body for a few seconds. No pulse at the injectors. Almost done now with the other engine harness ive been installing.

bagster · 10-06-2013, 01:12 PM

finished installing the wiring harness for the engine. Still same problem. I noticed a red light lit where the key symbol is on the center dashboard when i put the key in, is that normal? Also all my warning dash lights are lit when I am trying to start

BYprodriver · BYprodriver's Garage

Check or replace the crank position sensor at the flywheel. When it goes bad it cuts fuel to injectors.

bagster · 10-07-2013, 08:23 AM

That was actually the first thing I did. I had a spare cps, compared readings on the test. they were the same then ordered a new one and compared again. all the same.

jwgn777 · jwgn777's Garage

Quote:

Originally Posted by bagster

finished installing the wiring harness for the engine. Still same problem. I noticed a red light lit where the key symbol is on the center dashboard when i put the key in, is that normal? Also all my warning dash lights are lit when I am trying to start

Yes the lights on your dash will stay on until the engine runs then will soon go out. I would still concentrate on why your not getting power to the injectors. Did someone suggest that the harness was the problem?

bagster · 10-08-2013, 12:48 PM

Yea the guy that rebuilt the DME thought It might be the harness. I have a ignition electric switch coming in tomorrow. and a fuel pump relay on Thursday. gonna start cheap and simple. I just traced the W lead from the immobilizer to the trunk and it seems fine. Trying to find the K lead now. Don't know what it is. When I did the Autel scan these came up as problems with the immobilizer.

bagster · 10-10-2013, 03:27 PM

She fired UP!!!!! I replaced both ignition switch and fuel pump relay and it fired. I'm betting it was the ignition switch since I tested the relay and it seemed to be working. Runs and drives great!! thanks for all the info. It really helped

jwgn777 · jwgn777's Garage

Great news. Put that chain saw away. LOL