vigor

I put the key in the ignition, all electronics function properly, but car won't start.
It seems like it may be the clutch or a sensor at the clutch thats malfunctioning.
I hear a clicking noise whenever I step on clutch.
Checked fuses and they seem to be fine. It doesnt seem to be the key's codification since the electronics turn on and it opens the doors.

Anything else I should try?

BTW: this is a 99 boxster.

Macster

Need more details.

Does the engine crank but not fire/run?

Does the engine not crank at all?

Do you hear any clicking noise that can be the starter solenoid energizing then de-engerizing cause battery power way down?

If engine doesn't crank turn the key off and wiggle the steering wheel and press the clutch pedal all the way down and release and repeat several times, pumping the clutch pedal like you might do when you pump the brake pedal to flush/bleed the brakes.

Then turn the key to engine start again.

There are other things but not until more details on the engine's no start behaviour.

Sincerely,

Macster.

vigor

Engine doesn't crank at all. I hear no clicking noise except when stepping on clutch

Macster

Hmmm. The time my Boxster did this I ended up having the ignition switch assembly replaced. Before I had the switch replaced I eliminated the clutch/engine interlock switch (replaced it with a new one). No start symptom still occurred at about the same frequency as before.

Tech (Porsche tech) first tried to dup the no start symptom by wiggling the key, the wheel, pressing the clutch pedal down either partially or pumping it and the engine either started right up on cue or didn't start just like it was supposed to.

After getting old switch out tech commented that the switch didn't look too bad -- not nearly as bad as some he's replaced -- but I had no regrets. I can't stand a car that won't start and I was willing to throw parts at the no start symptom.

If you have access to a sophisticated ObdII code reader/data viewer try reading any error codes. If CEL not on (and assuming bulb not missing or burned out) then you can try reading pending codes. A Porsche specific diagnostic computer might be able to query the car's security system to see if there's any error codes in that system that provide a clue.

For the latter you will have to get the car to a shop equipped with one.

I will point out that even though the no start symptom appeared out of the blue and at very randon times with no fore-warning and on at least one occasion almost had me calling a tow truck the engine did start, eventually. But why it chose to start after not starting for at least once nearly 15 minutes of me trying everything I could think of and using every cuss word I had ever heard is beyond me.

And I will also point out that after a year or more after the new switch installed the symptom has returned though so far the engine has started up upon next try. In some cases I believe I'm accidently pressing the rear trunk lid unlock button concurrently with twisting the key and this pressing of the button interferes with the RF exchange between the car's security RF transceiver (located in the dash near the steering wheel) and the RFID pill in the key module. The rear trunk lid has never opened though so I'm not 100% sure my theory is on the right track.

Other times I maybe think the steering wheel may be the culprit.

Sorry but not much help I guess. Tough symptom to diagnose.

Sincerely,

Macster.

vigor

Thanks for the quick response.

The ignition turns fine, so I dont think that would be the problem, but I may be wrong.

I tried disconnecting the clutch switch and that didn't work.

At this point, I think it may be the starter or starter fuse.

Macster

I don't recall anyone who has posted of having an ignition switch problem reporting any difficulties with turning the key.

Mechanically the switch works just fine. What seems to be the problem is one or more limit or some kind of switch and electrical contacts are not made which either causes the security module to not broadcast an RF signal to the key module's RFID or in some what fails to cause the starter solenoid to be energized. Only if the solenoid is energized will the engine then turn over.

Disconnecting the clutch switch may cause the engine controller to believe the clutch is not depressed not the other way around.

How to bridge/wire/or in some way fool the clutch interlock switch into always signaling the clutch is depressed -- so the engine if it can start will start even with the clutch pedal not depressed at all -- has been posted. I do not recall the details but perhaps a search here for this info or an online search will turn up one or more of the posts.

My knowledge of the electrical systems of cars is pretty limited but if IIRC the current draw by the starter is so high I don't believe the circuit goes through the standard fuse box.

In the fuse box Row C number 2 position is the ignition relay/oxygen sensors relay. It is a 30 amp fuse/relay. That is the only fuse that looks like it is associatied with igntion/starting.

Sincerely,

Macster.

928FIXER

Floor mat balled up under cluth pedal???Pedal has to go allllllll the way down to floor for starter interlock contacts to make connection.First set to "clicks" you could be hearing are the cruise cancel contacts.

vigor

Took it to a porsche certified shop and they told me the immobilizer was all wet. Ordered that part and should be here Tuesday. They also stated that the car was throwing lots of alarm codes.

vigor

Checked all this and seemed fine. thanks

curt_928

when my car wasn't starting with the key twisting.. I needed a new ignition switch. Good luck finding the solution to the problem.

sjfehr

Ignition switches are super-cheap, the only cheap part on the car. And are so infamous for failure that they're practical a consumable part. I bought one to keep on hand just-in-case.

Would have been better if they cost 4x as much but didn't break.

curt_928

I bought a second switch as well when I replaced mine.. anticipating a second replacement in time..

Macster

"wet"? That'll do it. The box under the driver's seat? If your car has water there there's a cabin water leak. Common sources are backed up drains or a leaking window/door seal. Check bottom of doors and give each door a good shake for sounds of water sloshing. And check those drains! Front and rear.

The electronics under the seat will have to be dried out and hopefully it will prove ok once dry.

Sincerely,

Macster.

vigor

So I took the car to a porsche shop today where the could actually program the immobilizer. The one I purchased online was from another porsche which could not be programmed. Had to buy a brand new one for $391 + the $109 programming fee. They still could not turn the car on. No fault codes were showing up as well.

They stated it should be the starter relay and starter. Decided to take it with me and try to mess with it on my own. When I got back I tried to push start it, but it still won't turn on.

Now I'm thinking it's not the starter, but that the immobilizer is still not programmed correctly.

One thing they did do was make the remote function with the new immobilizer, which was not working before.

So what do you guys think? Could they have not programmed the unit correctly or what?

Macster

Hard to say. Obviously, if the steps are followed correctly the programming should work, and provided there is no other problem.

The general rule regarding cars and problems is there is always 2 problems, unless there is only one problem, or more than two problems.

There should be a way to verify the security module and key RFIDs are present and accounted for.

Also, one would hope that after programming the hardware, then the mechanic would have tried to start the engine and having the engine fail to start would have prompted him to go back and double-check his work.

I just tried removing the RFID from a key module and holding it with some fine tweezers. I have to hold the pill almost right where it fits in the module housing to work, but when I do so the engine cranks and starts then runs.

However, save for the engine's starting, or not starting, I could see no other signs the RFID was working.

I was hoping to see some evidence that it was at least being energized. Unfortunately I see nothing.

With the RFID removed from the module and the other keys on the roof of the car the key would turn in the ignition and the dash lights would come on and everything looked just like it always does, but the engine did not crank.

If the engine does not crank in your car's situation and does not push start this strongly suggests a problem with the security module/programming, or perhaps some other side effect from the security module having gotten wet.

Sorry, but that's all I can come up with at this time.

Sincerely,

Macster.