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Posted by: N14 Jul 23 2007, 04:20 PM

2 weeks back I took a 400 km drive from Vancouver stopping after 2 hours to walk the dog . The ignition would not turn over for 3 hours. On the way home I stopped once again but left the car running.......when I got home turned off the engine, tried to start it again - nothing. 3 odd hours later all was fine.

Is my starter over heated? Would it be the wiring?

Help please

Posted by: McMark Jul 23 2007, 04:22 PM

New starter (I like the eBay mini starters) or new battery cable/ground cables, or both!

Posted by: Coy Jul 23 2007, 04:37 PM

Along a similar vein, I turn the key and get nothing, not a click or a buzz, but the passenger light dims. a moment later I turn the key and it fires up. It'll do this both hot and cold. The dimming light tells me I'm getting a draw somewhere, so I don't suspect the ignition switch. The battery seems strong and when it's not doing absolutely nothing the starter starts strong...

I could try and cross the starter, but that doesn't tell me anything, because it might just start anyway.

Posted by: orthobiz Jul 23 2007, 05:35 PM

Since I got my car, the only repair I made was to replace the ignition switch. So, therefore and thusly, EVERYTHING is a broken ignition switch!

Paul

Posted by: SGB Jul 23 2007, 07:30 PM

Is the ol' transmission ground strap there? Its a braided copper strip bolted to the rear of the transaxle and bottom of the trunk floor.

Posted by: Vacca Rabite Jul 23 2007, 10:02 PM

Sounds like you are shorting out somewhere intermittantly. Time to start checking the wiring.

Zach

Posted by: Coy Jul 24 2007, 12:36 AM

Yah, but what's weird is I won't move... I won't get out of the seat and I'll just watch the lights dim, but on the third or forth try it'll fire off. ...Ignition switch?

Posted by: McMark Jul 24 2007, 02:16 AM

Coy, I'll remote diagnose a sick starter for you too! Seriously.

Posted by: Spoke Jul 24 2007, 05:17 AM

I had a similar problem which turned out to be an oxidated connection on the battery terminal. Car would start; car would start; car wouldn't start; no power.

It took a couple of days to isolate the issue. Since a bad electrical connection is hard to measure without a load, one of the times it wouldn't start; I got the dim dash lights; I turned on the parking lights to create a current draw, then went looking for a voltage drop with my voltmeter.

I'll find the voltage drop somewhere between the battery and the lights. Measured the battery on its terminals, not the clamps: 12V ok. Measured from battery terminal clamp to battery terminal clamp: 7V Yikes!

It was the positive battery terminal. It looked ok, clamp was tight. Issue was a thin layer of oxidation/corrosion between the terminal and clamp. I used my battery terminal cleaning tool, retightened the clamps and my no-starts are gone.


So for your issue, once it won't start, turn the lights on to create a load and go looking for voltage drops with your voltmeter. Don't have a voltmeter, buy one or buy a different car.

Spoke

Posted by: Coy Sep 3 2007, 01:49 AM

I cleaned the battery terminals and went to get a voltmeter (12 years of owning Porsches, motorcycles and various old pieces of crap and never had to use one).

A little over a month later... The situation has never happened again. Starts first try every time. I'm pretty sure Spokes was right... dirty battery terminal, even though it looked and felt clean.

Of course I don't know for sure because it works all the time now and because I forgot the voltmeter... I got the oil & filters though!

Posted by: swl Sep 3 2007, 06:26 AM

What year of car Andrew? Lots of good advise up there - particular the one about getting a voltmeter. Measure across the battery while attempting to crank. Then measure from yellow on the solenoid to ground. If there is a big difference then start working your way back to the switch. If the yellow is good try the big red to ground. If that is good then you've pretty much isolated it to the starter/solenoid.

Search on '+screwdriver +trick' to find an exciting alternative to the voltmeter.

Posted by: davep Sep 3 2007, 08:01 AM

You need to define 'won't start'.

What, exactly happens? Do you hear the fuel pump run for a few seconds? Is there any clicking from the starter solenoid?

Never underestimate the ability of the ignition switch to cause problems. If you have not replaced it in ten years, suspect it. It can short out and cause the lights to dim. It can open circuit and nothing happens.

If you cycle the ignition switch on/off/on/off can you hear the fuel pump run? Does it gurgle with vapors or simply build pressure. If you hear it gurgle then you need to cycle it until the vapors are pushed through.

Both the fuel pump and starter can get overheated. Usually this is caused by excess heat from the engine, the heater valves dumping hot air on the fuel pump (prior to 1975 models), missing air deflectors on the bottom of the engine firewall, or just poor attention to keeping the engine cool.

Before buying big ticket items like a fuel pump or a starter, check out the wiring first. Every connection, every ground strap, fuses, relays and so on. You could even install the hot start kit, but I caution you that this is usually only a cover-up for fundamental problems. The hot start kit is just a big relay (50 amp maybe?) for the starter solenoid. It takes the high current for the solenoid away from the ignition switch. Basically I suggest using this only after installing a new ignition switch to give the new switch an extended life. In my opinion, the ignition switch carries too high a current through wires that are too long.

Posted by: So.Cal.914 Sep 3 2007, 09:18 AM

I am a little confused here(my wife would tell you this is not unusal) you

say "The ignition would not turn over for 3 hours. " Do you mean to say the

ignition won't work or the starter won't spin? Please advise.

Posted by: Mark Garriott Sep 3 2007, 10:27 AM

This was a problem on two cars I had. Once the car gets hot, the cruddy old contacts in the ignition switch can't flow enough voltage to trip the starter solenoid. Make sure you get a geniune Porsche part, which will be 2x as what is available on the 'net.

Posted by: orthobiz Sep 3 2007, 10:53 AM

I just KNEW I was maybe on to something!

Paul

Posted by: Blood red 914-6gt Sep 3 2007, 12:12 PM

Okay.... How many of you guys having this problem have a 74? This is a common problem on a 74 as the seatbelt safty cut off malfunctions. It is the thing under the passenger seat. If you turn the car on and try to start it the relay will stops the ground from getting to the starter. You just need to take the two BIG yellow wires and connect them byepassing the relay.