ca993twin

Another thought (probably a lame one)... is it possible that your new starter is NOT retracting from the ring gear and is spinning like mad with the engine running? That will certainly heat-soak that starter. Good luck tracking this down... we are all following this thread with interest.

Vorsicht

No check engine light and no codes. Plenty of charge left in battery - starts up next day as if nothing has happened.

I assume I check resistance at the connector in back left engine bay. What value should I be looking for?

The oil temp sender seems to be operating normally at least according to dash gauge.

EckFe1

When the engine shuts off by itself, have you tried to crank the engine manually? 19mm wrench on the crank pulley and check if it will rotate easily until you get to the compression point and beyond to the next tdc and so on?
Maybe your tolerances are too tight and the motor will stall due to friction? Side load on thrust bearings?
Just a thought.
Ed

techman1

Low battery, alt not charging properly is my guess. See if the lights on makes it die sooner.

e3photo

Seems if it were a battery problem,it wouldn't fire right up after just sitting a few hours.


Emerald

techman1

I know, but it is the only thing that ties the two symptoms together.

trophy

I will see if I can find the resistance range for the sensors for you.

berni29

Hi

I would ignore the problem for now, get the car driveable and then let Porsche swap the harness. I know it will be touch and go getting there (you could trailer it). They can swap the starter for you at the same time i'm sure. They have to undo a lot of gubbins to get the harness changed, so it may well clear the issue. Plus all bets are off with the old harness. Mine was burnt to a crisp. Literally.

Best of luck

Berni

Rialas

Hoping it's something minor.

L23FPorsche

Wishing you the best. Have you got an update?

C4S993

After reading this and seeing all the critcal pictures; no way am I trying to rebuild my 993 case internals! When I was younger I was casually rebuilding engines in a Jag E-Type and some PontV6 and 'Vette V8 and those were no problem(s), but these 993 engines are in a league all by themselves. I could handle the heads/cams and pistons, but the case itself seems daunting ! Wonder what Steve would charge to straightforward rebuild a shipped 993N/A or 993TT case shipped to him ?

Mike J

I think the key is a lot of prep, research and to be very meticulous, going step by step. The Pelican engine rebuilding forum is especially helpful, lots more technical knowledge specific to engines than on this forum, and you can get lots of help (and opinions of course..)

If you have done other engines, a 993 is well within your capability, and in fact you can do it twice for what a engine rebuilder would charge, given your labour is free. Its 30-40hrs min for a complete teardown and rebuild, with splitting the case, and then there is the cost of machining, new parts, gaskets, etc.

Unless something really major has happened to your engine, the bottom end of the 993 (possibility excluding a slightly weaker rod bolts) will last a long long time, so most rebuilds revolve around valve jobs and sometimes replacing the rings. I split the case on my rebuild just because I was there, but I found everything was in spec and it was not required. There was a bit of wear on the layshaft bearings (typical) but nothing that would not have gone for another 100,000 miles.

Cheers,

Mike

Vorsicht

Here's the update. The posts about tolerances being too tight got me down but made me think through how this could have happened.

I went back and reviewed all my pictures of the tolerances (showing plastigauge) for both the mains and the rods. All were well within spec.

Additionally, I remembered that his symptom (shut down)happened BEFORE I even opened the bottom end. As I know, anything is possible, but I am hoping to find something else.

So I finally got my laptop running (another story) and was able to attach my scantool and read the codes. Lo and behold I got one: Code 1118, RPM Signal.

I was super careful when I attached the sensor to the case and carefully measured the gap. It was 1mm.

My next thought is could I have mixed up the connections in the back left engine area so I will be checking that next. IIRC, they are all color coded and I matched the colors but I'll have to do a double check.

I'm also gonna run the car until shut-off with the scan tool attached and see if I get strange RPM signals near the end when it gets hot.

Then I will try to advance the engine by hand and prey that it will move.

trophy

Hey Peter,

You are right with the color coded plugs for the Head Temp and reference sensor.

Check to see if the wire for the reference sensor hasn't been damaged, crushed etc.

There is a test for the reference sensor, however you need access to an oscilloscope to do the testing. If you have access you connect the oscilloscope leads to pins 48 and 49 on the DME and check the signal, you are looking for at least 3v and a good saw tooth pattern.

Vorsicht

Will be checking wire - maybe got caught somewhere. No O-scope. I have now seen the word, "oscilloscope" enough to know I should buy one if I come across at a garage sale. We still live in an analog world...