Porsche Enthusiasts Club Forum

Thanks man! For the sake of running the car with the cap off for a few mins, I'm willing to give that a go (and check the rest of the breather system too...)

About to whip the injectors out in my lunch hour and take them down to a local specialist for a test / clean and then at least I'll know that they're either OK or not. Can't hurt to have them cleaned at any rate

All cleaned and resealed... and missing. Throttle position sensor next, as that's throwing out some kinky numbers... after that it'll be DME

I guess I can always get scrappage for it, get a nice Ka... great for trips to the shops and to the retail park restaurant...

I did try this, alas and alack... no dice.

Head's coming off... am of the impression that something is awry in number 4... as soon as I get the crank bolt undone then things should start to come apart quite quickly

Blimey!

Sorry to desert you all for a bit, had some repercussions of last summers hospital stay, kidneys, almost back on my feet again now.

Anyway, it may be that your head gasket is in a bad way, sometimes they can degrade with age.

We had a lux in last year which just had a rough running fault, which we tested every dynamic of the car. Compression, leakdown, every sensor, ecu.. Nothing seemed to be wrong and nothing seemed to be the cause of the hard starting occasionally and a slight flat spot.

Eventually we decided to take it for an italian tune up test drive, with the customers authorisation to see what it did when driven hard... We only got about a mile before the head gasket failed.. Once the head was removed the headgasket that came off looked like it had been hit with both barrels of a shotgun!! New head gasket not only dealt with the smoke screen the italian tune up caused, but also completely cured the hard start and the flat spot.

Another reason why these days we recommend people change their head gaskets every 10 years. These days the 944's are not being used to clock up massive yearly mileages, so things like head gaskets are not failing routinely, but now seem to be failing slowly and causing more of a problem with diagnosis of various issues.

So it "could" be your problem.

Have you checked the fuel pressure?

If it were an S2, I would recommend you take a look at your valve springs. Not had to change many recently, but about 5 years ago we were having to change them on almost a weekly basis due to misfires. More often than not high rpm misfires though.

Bloody hell, and you're devoting brain cycles to my misfire?! *salutes*

Well we're waiting for the flywheel locking tool to get the 24mm crank pulley nut off, and then the head can come to bits. Jamie has priced me up all the bits (worst case inc. full set of valves, springs etc.) so once that little cork is popped I can crack on.

Really value your experience and insight Jon. I feel satisfied that the diagnosis has been methodical and complete and the variable compression result points toward the head needing to come off (oil down bore didn't improve things - so perhaps with a schoolboy C&G mentality I'm eliminating rings from the mix and confining issues to the head or the head gasket). I really welcome your experiences and views, you've a vantage point that I can only guess at, and some of the things I've eliminated I would *never* have thought of (e.g. earth strap).

OK, back to this one...

Thanks to JMG for the crankshaft locking tool, Broady and me were able to undo the crank bolt tonight so we can crack on. I decided to drain the oil while we had it up in the air and as I removed the sump plug my heart sank...

Lurking in the oil... by iancleary, on Flickr

Speculation? Looks too thin for a valve seat, so I'm hoping it's a spring retainer that's broken and found its way cleanly into the sump... am hoping to find 100% of the other bits in the cam box, otherwise it's going to be a messy job to strip the bottom end too

Guess my JMG order is looking pretty chunky now... shall be on the phone to Jamie in the morning, and once the head is off I reckon it'll be diagnosis and rebuild time.

Thoughts from the floor?

Ouch, not good Ian, hope you find all the bits of that

Oh dear I guess that nice clean hand is not going to stay that way

Here's hoping it is not more than a head job.

Should have bought that turbo, eh?

Oh well, it managed 30 years without an engine rebuild... the poor bugger deserves it, and as I feather the brakes, sliding into Lincolnshire corners at 80mph+ or nose it forward along autobahns and Alpine sweepers I will love it all the more for knowing every capillary in its pounding heart.

It'll be covered in blood and grease before its fingers grip the supple brown leather of my '44s wheel again in anger... and all the better for it!

Sorry I have not been back to check on your progress.

We had a 944 lux which a customer complained of an occasional rough idle and sometimes poor cold startup... Turned out to be a head gasket on its way out.. The car had passed a compression test, leakdown test, no evidence of hydrocarbons in the coolant and never suffered coolant loss.. But having taken the car for an "italian tune up" with the customers permission, the head gasket let go and made itself obvious.

After a head gasket replacement the car ran fine.

In the meantime, other options might be a bad wire in the loom, so it may be worth checking the loom with a wiggle test, go around all the wiring in the engine bay wiggling wires and connectors and see if any cause the fault to happen or any odd blips.

Another test would be to use a can of WD40 and spray it in short squirts all around your intake manifold, you might have the slightest leak there somewhere which is causing one or more cylinder to be a little more lean at times. In the workshop we have a smoke tester which is useful for this.

Well, it lives...

After weeks of committed and sterling work from Broady, supported by parts and advice from JMG, we finally got to turn the key tonight...

The cause of the issue was a broken valve spring and bottom spring retainer, although Broady discovered that the oil cooler seals, head gasket and numerous other sundries were on the verge of giving up the ghost so it was a well timed rebuild. In the time the car has been in bits the MOT has expired and the tax also, so the next couple of days will involve putting it in for MOT and taxing it, putting a few miles on the car and then dumping the coolant and oil at 500 miles before heading down for a couple of days at JMG for an inspection and some setting-up work.

The Puff was already a keeper, but sure as hell it is now! I've got "more than its present value" invested and tonight when it sputtered into life (bit of a tense few minutes before the new parts quietened down and a couple of "ah right" moments with pipes off and bits) I was all smiles. It sounds ACE, much smoother than before and I can't wait to get back down the road in it. Shame it's the wrong end of the year but that means a Winter of fitting up other parts I've accumulated and general fettling and grooming ready for the Spring.

Who needs a 911, lovely as they are? Who needs a 951, even... No, I love my 945 and I'm dead excited now for the next chapter!

Glad to read that you're back up and running!

Just seen that you're in Redbourne...My folks are nearby in Waddingham so when I'm in the area I'll be sure to give you a bell!