hawk911

so the mechanic is telling me that the engine requires even pressure with the fuel injection before it will start. Is this blinker fluid talk?

Also, he says the top of the piston looks like there has been foreign material across it. Not being able to see it, I'm taking it at face value.

Jacke2c

Sorry about my most recent post. There were only four when I made my comments. All of the sudden there's andditonal 10. My comments seem to be out of order..... however, did they snake a magnet in the plug hole to catch a piece of shrapnel?

Jacke2c

All of the injectors see the same pressure. They are on a common fuel rail. Are they saying it is not getting fuel?

hawk911

maybe I misunderstood him earlier, but he's telling me the top of the piston has markings like something has gone across it. he's telling me if the injectors DON"T see the same pressure, the engine won't turn over

Jacke2c

The fuel pressures receive fuel directly from the pump after passing though the filter. The fule travels across a common rail (actually two connected by a rubber hose). The rubber hose has a "t" connector that has a spring loaded backpressure valve. Once the pressure reached the facotry set spring back pressure, the excess returns back to the fuel tank.

I am suspicious that you backpressure valve may be faulty and could have been stuck open, thereby not allowing your injectors to see the amount of fuel required to run your car.

The scrapes across the piston top could be something casued by spark plug threads from the last change/tune-up, small part falling from the throttle body into the intake, etc.

I still say, make it run and drive it for a little bit to see if it smooths out.

I once overhauled a gmc v-6 in my wife's astro van. Set the valves and had a horrible time getting the old lifters to pump back up. after four repeated attempts to set the valves, they finally came up. They set empty for only 2 weeks while I had the machine work done. Once up, and driven regulalry, they stayed pumped up..... I feel your pain. Hang in there, it may not be as bad as you think... I hope not anyway. Jack

ChaseN

Wouldn't that require a sensor at each injector to monitor that pressure?

Correct me if I'm wrong, but, I know of no such device on a 964...


I agree with the others, get it running. My '74 sat for 30 years without running. I'm sure the leakdown numbers would have been horrible. I got it running with no internal engine work and it was fine.

hawk911

As a photographer, i hate to be told how to take pictures.... nothing worse than an amateur digital debbie or digital dan telling me how to shoot. So, not having any experience in Porsche engine repair, I hate to tell him "well, I saw this on the forums... did you try this?"



so how do I tell this guy to keep digging if he feels the cylinder/valve issue is really what's preventing the car from starting?

Jack, where is this valve you speak of?

August West

You mentioned your son may have been the last one to drive it...were you with him when he drove it?

hawk911

I was ahead of... about 500 ft. If it was overrevved, wouldn't more than 1 valve/cylinder leakdown be bad? and he was scared to drive it

LouZ

The $1700 was for the parts, I spent $5,000 more on beer and food!

Jay H

Geoff,

I'd still suggest calling Kelly Moss on this issue. Even if you have to trailer the car out to Madison, keep in mind that they build some very good Porsche race cars, so there are decent mechanics there in the race shop that can at least guide the street mechanics if need be. Or, start quizzing the ChicagoLand shops as well for another opinion.

I agree with others that this motor should run. I heard it run all day during the tour before she quit on you and it made it the whole way home later that weekend.

I wouldn't argue with the shop that has it now. Get the trailer, load her up and get a second opinion.

ja78911sc

I would ask him what will it take to get the fuel issue resolved. If he is offended by this question, then pick up the car and take it to another shop to "trouble shoot" the fuel issue. In my opinion, this is where you need to start. The car ran fine and now it will not start.

You may very well have a motor issue but I would do everything I could to rule it out before i proceed with an overhaul.

SuperUser

Man, I am so sorry to hear this:-(

Makmov

I agree is there sounds like there is more too it than what has been discovered already.

Have you told the people working on everything you know up to this point?

There are some mysteries there for sure.

Makmov

Sounds like an engine for sure but don't want to burn up another one if it was something that cuased this one to fail like a lean situation.

I agree need to find out what happened.

It's easy to say it was running fine and BLAMO KABOOM.

But when it was running okay for a whole day and wouldn't start back up... now there is bits in the chamber... that doesn't add up.