Non Starting 1997 Boxster

[fahmasan]

Hi guys, Already bald so no hair pulling! My Porsche is driving me nuts. When I turn the key (new switch) nothing happens at all. It started doing this about a month ago, got progressively worse, now nothing. Lights all come on, new battery, new starter, new ignition switch, and new immobilizer (year old). What could I have missed?
If you turn the car to start, should there at least be a click or some sound? Next move is Craigslist LOL. Any and all advice is greatly appreciated.
I also replaced the clutch switch.

[particlewave]

What happens when you bypass the start lock relay and turn the key?

[fahmasan]

Not sure what or where the relay is. I do know where the starter relay is. Is this what you are referring to?

[Turbodad]

Is it a Tiptronic? If so check the shift cable in the engine compartment. Make sure the cable is to the passenger side of the bracket going over the engine, looking from the back.

[fahmasan]

Sorry, it is a five speed

[particlewave]

It's the relay directly above the large fuse in the rear trunk relay panel (#7).
Do you hear the fuel pump prime when you turn the key to on position? Have you checked/bypassed the clutch switch?

[Boxtaboy]

I agree with PW. Check the clutch interlock switch first as it's an easy fix if that's the problem. Link below that explains in further detail...

If a manual equipped car suspect the clutch interlock switch. My 02 did this and I had the...

[fahmasan]

Thanks for the reply guys. I replaced the clutch switch with a new one. Worked for a few days, back to the original problem. Just bought a new relay and another ignition switch. The box under the seat was replaced about a year ago, it looks fine. Really stumped on this one. Does the door locking mechanism have anything to do with starting? Seems to work fine with the key button. Thanks again!

[Boxtaboy]

Weird that the new clutch switch worked for a few days. Maybe ziptie the clutch switch to bypass it to see if that is the source of the problem. I doubt the door look has anything to do with it.

[Anker]

My theory is that there is mouse damage. Occasional shorts caused by insulation gnawed off wires. That will give this kind of intermittent error. Every time you mess with the car you may jiggle the wires enough to clear the short, but when driving the cables jiggle back to the short.

Good luck/Anker

[particlewave]

The start lock relay locks out the starter until all security parameters are met (clutch switch, transponder recognition). Bypassing will get it to crank, assuming the battery, starter and all connections are good.

Rather than replacing the relay, you should bypass it first to see if it cranks and fires or just cranks. That will give a place to start troubleshooting. Bypass it by removing it and placing a jumper wire between the socket terminals 30 and 87.

When you say the lights come on, do you mean the dash lights? Can you hear the fuel pump when you switch the key on?

[fahmasan]

Again, thanks for the help. I bypassed the clutch switch, that worked for a couple of times. As far as the relay, which points are 30/87 on the four point relay? Sorry for the ignorance, by the time I finish with this, I'll be helping Wayne with an updated version of his book! Also, don't see any wiring damage. When I turn the key, all dash lights, heater fan, and fuel pump items work, but no effort from the brand new starter at all.

[particlewave]

It's the one "horizontal" and middle "vertical".



This is a different car, but same principle and connections.

[fahmasan]

Thank you. Will try that today.

[fahmasan]

PW, Did as you suggested and jumped the starter relay points. Car fired right up and then shut down. What should I try next? Thanks in advance. I also tried a new relay, no go, nothing.

[particlewave]

So, it ran off of the fuel pressure in the line from priming.

I'm leaning toward an immobilizer issue. From your description, I think you have an intermittent connection. The way it got progressively worse leads me to believe it's corrosion somewhere. Why was the immobilizer replaced? Water damage? If that's the case, I'd suspect corrosion on its connectors. Mice are also a possibility.
Check the immobilizer connectors for corrosion or loose pins (disconnect battery first).
Verify the immobilizer fuse is good (it's on the immobilizer).

[fahmasan]

Thanks again PW. Will do as advised. Right now with the jumper it just turns over and doesn't fire. The immobilizer was replaced because of water. I will clean it and let you know. Much appreciation for your time.

[Boxtaboy]

Another forum member had a similar problem recently I think. Turned out it was a mouse had chewed through some wires leading to the immobilizer.

[fahmasan]

Thanks. I took out the seat and checked all of the wiring I could see. Seemed fine. I also disconnected the connections and sprayed them with a cleaner. Letting them dry now. BTW when I push the lock button on the key, I can hear a distinct click inside the box. Good or bad?

[fahmasan]

Problem solved thanks to all on this forum. It was the box under the seat. Cleaned the connector with electrical cleaner, let it sit overnight, and viola! Fired right up.

Many thanks again to all that replied!