Need Help Bigtime! - 986 Forum - The Community for Porsche Boxster & Cayman Owners

JebLacey · 11-26-2005, 04:40 PM

Hi Everyone... This one might be a little long, so bear with me.

99 Box, Tip, 63Kmiles, strong motor, major done at 52K.

Here is the deal. I started having an intermittant problem, with the transmission going to "safe" mode, and the CEL popping up. It happened in 2 consecutive drive cycles, each time, I stopped the car, and re-started... no probs for the rest of the drive. I took the car down to a local AutoZone, and had the DTC read. I only got back P0600 (Serial Port Malf... PCM trouble communicating) I have not been able to get into a Porsche shop to get the specific code, since the long weekend closed them down, plus, I am kinda stubborn.

Anyhow, yesterday, noticed that the CEL was not coming on when i turned the key, before start. Then I tried to start, and it would not fire. The starter turns and turns (lights flash between P and D), but it sounds like no fuel. I came back out a few minutes later, the CEL was back, and the engine started. Now, it only starts when it wants to, which is about one out of every 20 tries, but i have noticed that the CEL is absent on the ones where it does not start, and always comes on when it does. I dont know what that means exactly. Has anyone ever experienced this?

Lastly, I thought it was a problem with the selector switch in the trans... but if it was, wouldnt the top not go up or down either? Now i am thinking that i have no idea what is going on. The nearest dealership is 100miles, and I dont really trust local shops other than to read codes. Let me know what you think....

P.S. Not to complicate things, but it fired perfectly about 10 times in a row today while i had the door taken apart to fix a regulator that had jumped a rail. Once i got the door back together, it stopped working (i.e. No CEL at Accessory Key, no vroom vroom). Could a short in the door somewhere cause the CEL not to test, and the fuel not to flow?

mjw930 · 11-26-2005, 07:13 PM

Check the battery connections. Clean them and reinstall them. You would be surprised how many phantom electronics problems are caused by low current situations.

If that doesn't work then make sure the connectors are tight on the computer.

JebLacey · 11-27-2005, 07:51 AM

Sounds good. I have already cleaned the ground, but I will go clean the positive side good too.

Question. Which box in the back is the ECU, and which is the Tip Trans Controller. Also, how exactly do those connectors come off? You pull down the metal clasp, then what? It is a little confusing, and i dont want to force anything.

I will keep you all updated as to my progress. Thanks for the help.

JebLacey · 11-27-2005, 11:14 AM

So I cleaned my battery posts/connectors, cleaned the ground, and the connector for the Pos. into the firewall. I checked the connectors on the DME and the Tip. controller, but dont know which is which (checked both, both secure and appear in good order). Went to start it... no CEL test light. Tryed to start anyway, and of course, no luck. Starter just spun.

How do I disconnect the DME and Tip Cont. Want to check the connections themselves... Do i have to un-mount them from the wall?

mjw930 · 11-28-2005, 05:17 AM

Quote:

Originally Posted by JebLacey

So I cleaned my battery posts/connectors, cleaned the ground, and the connector for the Pos. into the firewall. I checked the connectors on the DME and the Tip. controller, but dont know which is which (checked both, both secure and appear in good order). Went to start it... no CEL test light. Tryed to start anyway, and of course, no luck. Starter just spun.

How do I disconnect the DME and Tip Cont. Want to check the connections themselves... Do i have to un-mount them from the wall?

At this point I think the dealer or a good independant shop who knows the Boxster / 996 electronics is your best solution. If could be something as simple as a failed relay.