3.2 Carrera will not start

[Peter Roberts]

I am planning of selling my collection of cars which includes a stunning 3.2 Carrera Super Sport. I has been dry stored for several years like the rest of the collection so i am preparing it for sale.
Unfortunately i cannot get it to fire not even to cough. i Have established the following;-
1) I have a spark
2) On turning over the rev counter bounces a little which suggests the flywheel sensor is ok
3) I have broken into the fuel line near the injectors and there appears to be fuel there however i will look for a tapping point and put a pressure gauge in to check
4) DME relay is the obvious place i started. Replaced the unit but no joy. Put on ignition and there is a whirring noise from under the dashboard that sounds like a motor but not sure what it is.. If i short out the terminals 30 and 87 on the DME plug i cannot hear the pump start up but it may be very quiet as i seem to have fuel at the injector rail.
Any other suggestions would be appreciated.

[inaglasshouse]

If i short out the terminals 30 and 87 on the DME plug i cannot hear the pump start up but it may be very quiet as i seem to have fuel at the injector rail.

Not had a 3.2 but every Porsche I've known, from '65 to 993, has an audible fuel pump.... short out the DME again (or just put the ignition on if the DME is not prime suspect), and visit the pump. Can you feel it vibrating? If seemingly not working, first thing I would try on a car that has sat for a long time would be a bash on the pump with a rubber mallet!

Other obvious one is stale fuel.

[Nige]

Fuel pump is definitely audible if working. There is also the odd buzz and click from the back of the dash, but that is just other stuff.

You should certainly hear the pump especially if you put your head near the petrol tank with the boot lid open.

As suggested above mallet and fresh fuel, you can also put 12v direct to it, maybe give it a quick buzz in reverse too.

[Peter Roberts]

Jumped the teminals on the dME plug and pump is running but will not start. Now ordered an adaptor to check injector rail pressure

[dean1057]

If there is no spark it will be flywheel crank sensor.
Had one go on me and you end up with no spark.
http://forums.pelicanparts.com/porsche- ... e-car.html

[dean1057]

Forget that, just seen you have spark. Doh!

[Peter Roberts]

Now I am struggling?
Petrol is fresh as it has not been run for about 5 years
I have a spark
The rev counter bounces on turning over suggesting the flywheel sensor is ok
I have 45psi in the injection rail when cranking
Removed a plug. Perfect condition and slightly damp which you would expect having tried to start it several times.
It does not even cough despite turning it over continuously
I am not giving up but.as it is going on sale and as an SSE will contribute nicely to my pension but would hate to call somebody in if it turns out to be a simple problem.

[sladey]

I’m reading that as if the petrol is 5 years old. Which is not fresh. Am I misreading it? Petrol in my mower goes off over the winter months.


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[Jonny Hart]

Gummed up injectors. Common on 3.2.

[Sam]

The plugs are wet tho.

Have you got 12v both sides of the coil?

Does the idle control valve hum with the ignition on?

Speed sensor and reference sensor are common failures that cause starting issues. You can check their resistance to determine failure but I can’t remember which pins or what it should be.

You can download workshop manuals here: https://www.dropbox.com/s/33gi4678e0psm ... s.zip?dl=0

It’ll be in there.

[Jonny Hart]

^ He said 'slightly damp' on one plug. Doesn't prove fuel.

[RobFrost]

Cylinders flooded or no fuel, or foreign fluid (Water, diesel or bad petrol) in fuel.

Combustion requires ignition, compression and fuel.

No compression is unlikely.

You say you have spark. If you've pulled a plug, it's clean, gap is correct and you have spark at plug when turning over, I'm happy you have spark.

Ergo you have no fuel.

If however plug is too wet to spark you may have no spark.

If not firing but fuel is being delivered, cylinders and plugs should become fuelly and exhaust should be emitting smellable fuel vapours.

Check what fluid is on your plugs, make sure it's petrol. Also, use double battery or jump leads for strong starting.

Heat engine with a fan heater.

I'm assuming ignition leads have not been off. If those have been off, they become a suspect.

Assuming all else in order, I'm going with gummed up injectors as mentioned above.


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[Sam]

^ He said 'slightly damp' on one plug. Doesn't prove fuel.

True, but I bet it’s electrical. It’s always electrical until it isn’t.

[Jonny Hart]

If you think it’s electrical, it’s probably fuel.

[Peter Roberts]

How embarrassing is this.
Watched hours of YouTube on testing, got all the figures for static and dynamic testing of the flywheel sensors, new battery in my digital tester, made bypass harness for the DME RELAY and bought a bottle of easy start. I also now know how to set up a test and clean out the injectors using brake cleaner.
Before setting out on this diagnostic journey I rechecked all the advice you super people offered me and latched onto the simplest suggestion first. HIT THE INJECTORS WITH A HAMMER. With a friend turning it over one gentle tap on the first injector and it coughed. Some gentle taps on the other injectors and it burst into life after years of storage. Perfect oil pressure no smoke just the gentle burble of a flat six ticking over.
Cannot thank you people enough for taking the trouble to respond to my woes. Thank you.
Now to give it a good clean and write the advert. Anyone looking for an SSE?