996 idle and starting issues. Help!

[hemeoncdoc]

I replaced the starter on my 99 996. When I turned the key, it would only intermittently turn over. Not a battery problem, I suspected the starter. I replaced the starter, and the problem is no better. I replaced the clutch cut-out switch also.

It will turn over after I pump the clutch pedal, turn the key several times, and eventually the starter turns over (vigorously), and it fires up. I bought a starter relay, thinking that it sounds like a relay, but I can't find where it goes???

I also have a new problem with the idle that developed following the starter replacement. After starting, it builds to a fast idle, around 2000 rpm. The engine runs well at faster rpm's. Checked the vacuum lines, they all look ok. I reset the DME, no better. The mass-flow sensor looks clean. Any help re the idle problem and the starting problem would be greatly appreciated!!

[Rrrockhound]

Your starting problem sounds to me like an ignition switch issue. That's a common failure area on these cars. Not sure about your idle problem but it's pretty common for people to post that after working on something else, the idle is funky--probably something didn't go back together right. I'd re-check all the vacuum lines.

[hemeoncdoc]

I ran through the vacuum tubing AGAIN. All of the tubing was intact. However, I found that a one-way valve in the vacuum line to the left of the starter was clogged with what looked like oil!? I blew it out, hooked it all up, and it runs great. Thanks for the tip. Bizarre - some cheap plastic one way valve. Dunno how oil could have gotten into that line. Wish there was an easier way to put the throttle body back in place - what a PIA!!! The ignition switch makes sense - though another frustration with Porsche that after only 51K miles something like that needs to be replaced. My 68 911 with 90 K miles is still working fine on the first one. I ordered the parts from Pelican - along with an AutoEnginuity setup.

Having worked with air cooled 911's my entire adult life, there is much to be said for the relative simplicity of those engines!
Thanks again for the tip.

[rb101]

I've found that if there is oil in the vacuum lines, its cause is a bad AOS.

[hemeoncdoc]

Just replaced the ignition switch, fixed the problem. Thanks for the tip. Now I smell a ton of oil burning - wouldn't be surprised if the AOS IS bad.
I guess I will do the IMS, RMS, and clutch while I am at it.
Gotta love it - and only 51K miles!!!

[hemeoncdoc]

Well, I thought that the starting problem was fixed. Admittedly, I had to turn the key 3 times before it would start after I replaced the ignition switch. After that, it fired up each time I turned the key for maybe 4 tries. The following morning- no improvement. Needed to turn the key 10 or more times before the starter turns. When the starter works, it does so vigorously, and always starts the car.
So far... I replaced the starter. I replaced the ignition. No problem with wiring to starter, to battery, or ground. I bought the "starter relay" but have yet to replace it, as I cannot seem to figure out where it goes.
Any help would be greatly appreciated.

[wanabe911 owner]

Did you figure this out yet?

[hemeoncdoc]

No. Noone seems to know where the starter relay is - if in fact that is the problem. I replaced the only other 2 elements in the starter circuit that I can think of. The ignition switch is much "tighter", clearly had some wear, but didn't fix it.
Someone suggested that the starter relay was under the rear carpet where the ECU is. However, none of those relays share the same part number. I replaced them one by one just in case - to no avail.
At this point, I may have to resort to the local dealership. However, they are both incompetent and expensive. Perhaps I am as incompetent at this point!?

[Rrrockhound]

According to Streather's book: "The starter relay (no. 7) is located on relay panel no. 2, which is located in the rear of the passenger compartment near to the DME." The picture in the book shows a relay panel that looks to be just behind the driver's side pop-up roll hoop. I don't know where that translates to on a coupe because I have a cabrio. At least with a relay, you can test it by borrowing another relay from another system in the car before you pop for a new relay.

[hemeoncdoc]

Thank you Rrrockhound. Found and replaced the relay. Unfortunately still has the starting problem. Very weird. I have found that if I turn the key and hold it in the "start" position, sometimes after 20 to 45 seconds it will then engage the starter and fire up. If not, generally if I then turn the key to the off position, then it starts right up. I have now replaced the (entire) ignition switch, the starter, and the relay. I have not replaced the ground wire to the starter, though it looked ok. I can't imagine what is left. Anyone know where the ground wire to the starter connects to the car? Anyone have any suggestions? Thanks