Hello,

I live in Bogota, Colombia and my 951 is with my wife in kids in DC. I visit once every two months and my wife faithfully (she hates it) starts my 951 every Saturday and lets it run for 15 minutes. It normally starts within 1 second of turning the key. When I visit, I drive it around town. This has worked well for 8 months. Now I have a problem.

When I was back in DC 3 weeks ago, I tried to start the car. The battery (Odyssey dry cell) was completely dead. It was at full charge the week before when my wife started the car. After connecting the car to a booster pack, the engine cranked freely but there was no sign of it starting. The interior had power and the wide band O2 sensor showed the normal display. I ran the battery pack out of juice 3 times with no sign of the engine catching.

I will be back in DC in 2 weeks and I want to get my car running again. I was going to start by buying a stock battery. Once the car is fixed, I will replace the dry cell.

Any thoughts on what could have happened? Something electrical went wrong and killed the battery. I am guessing that the same problem is preventing the car from starting.

Before returning to the U.S., I would like to have a strategy. I will only be there for a few days and my family complains if they do not have my full attention.

All advice appreciated. Thanks, Bill

 

could a latch not be closed causing lights to run the whole time?

If you can get it started jumping the battery then it seems an easy enough fix. Perhaps testing the alternator will point out that as an issue if you get that far. Seems a stretch, but perhaps it is as simple as fuses and/or relays that shorted.

 

The dead battery is not the root cause. Using the power pack, the car has plenty of electricity to power the starter and accessories. When cranking, the engine does not start.

I checked the fuses and relays. There was no visible problem.

I am guessing one of the systems in car failed and drained the battery. The same failed system is preventing the car from starting. Thoughts?

 

Alarm module comes to mind.Test is to jumper the DME relay and see if it starts.

 

I can only imagine how little time you can give to the car if you can only get home one weekend event two months... So have her do some of the work now.

I'd start by figuring out if the DME/KLR is getting power. With the battery fully charged, have her turn the key on (just before cranking). If the DME/KLR is getting power, the boost gauge in the dash will move up to about 1. If the boost gauge does not go to 1, then you know to look for things that would keep the power from getting to the DME -- relay, alarm, ignition switch, harness, etc.

If the boost gauge goes to 1, then have her crank it and watch to see if the tach twitches at all, or does it just sit dead as a door ****? If dead, then speed/ref sensors or wires are likely suspects.

As for stuff that can break and both drain the battery and prevent the car from starting, the list is pretty long I imagine... Ignition switch (keeping accessories powered), alarm malfunction, bad DME or KLR, harness short, etc....

 

How honest is your wife?

 

My seven year old is in love with car. He sits in the passenger seat when my wife starts it. My wife may have it in for my car, but she would never do anything to disappoint my son. I trust her.

My daughter is also an enthusiast. When she turns 16 and a half, I am sending her to the Bob Bondurant school of high performance driving. She is partial to Shelby Mustangs. I am trying to win her over to Porsches. I am planning on surprising her with a Porsche Boxter on her 16th birthday.

My wife is probably going to kill me for infecting the next generation.

 

Thanks for the advice. The boost gauge has not worked in years and I have an electronic unit. It has power. I had the wiring harness replaced a few years ago ($$$). I replaced the speed and reference sensors last year. I will check the tach to see if there is a wiring fault. I replaced the DME with a new unit a few years back ($$$). I do not think the car has an alarm. In order to save weight, I had the shop remove all unnecessary accessories.

It looks like I am going to busy in August. Thanks for the support.

 

I would ask wifey to make sure that neither turn signal is on and no driving lights, since that's easy.

 

But the car still does not start running on the booster battery pack. The driving lights or turn signal would only discharge the battery.

 

bad alternator

 

Sounds like maybe the DME relay. Similar thing happened to me several months ago. Started the car in the morning, it started and ran fine. Went to start the car later in the day with a buddy, it cranked fine but wouldn't catch. Replaced the DME relay (after advice from those here on the Rennlist and Clark's) and it was good as new again. I keep a spare in the glove box now

 

A DME relay is cheap, fast and easy. Looking through my receipts I replaced the last one in August 2012. I purchased the URO Parts from Lindsey Racing for $16.95. LR also sells a Stribel (OEM) for $36.95.

Any thought about a quality difference between the aftermarket and OEM?

 

It was replaced in 2012 with a rebuilt unit. Could a bad alternator discharge a battery while the car is parked?

 

No diff. Total luck of the draw on dme relays. Some suck and some last for years. No brand difference.