Noobie - No start 87' Carerra

OttoBob · 06-02-2013, 06:05 PM

My recent purchase - 1987 Carrera decided not to start after routinely starting and pulling it out of the garage Friday morning. I parked it for 10 minutes while I got my BMW E30 out (weekend autocross event). When I went to put the Porsche back in the garage, turned the key and no start. No cranking at all. A small hum. Battery has 12 volts. All other power works just fine. The car has not hesitated starting one bit in the two months prior to this. I've been gone for the weekend, still no start. Searched threads for "No start", can't seem to find one that matches my problem. Any help would be greatly appreciated!

DRACO A5OG · DRACO A5OG's Garage

12.0 volts is too low. Our 911s need 12.6 volts to crank. Jump it, it should start, consider gettung a battery tender like a C-tek 3300.

Btw, welcome aboard!

Pic please

OttoBob · 06-02-2013, 06:55 PM

Actually it was 12.23 volts on Friday, now it is 12.11 volts. It is on the charger as we speak. In the meantime here are some photos. Thanks for the welcome. The interior is undergoing some changes/renovation. My car is a GEM as you can see by the plates the DMV happened to be issuing!

DRACO A5OG · DRACO A5OG's Garage

Indeed a GEM

If you don't want to keep it on a tender, disconnect the negative side of the battery.

Remember she loves to be driven, she will punish you if you don't as she did :-P

If you do not drive her often, then after she is warmed up properly give her a good italian tune up to get the carbon deposits out her back side.

Enjoy, she really is a Red Beauty.

Jim

OttoBob · 06-02-2013, 07:37 PM

Charged to 100%, 12.82 volts, still no start. I was driving it every day for the past week! I have a battery tender for my winter car. I will get another one for the Porsche. Could it be the DME relay? I keep reading that a Porsche owner should have a spare one at all times? Where is it, and how do you check to see if it is any good?

ganun · ganun's Garage

➕1, if below 12.5v it should be charged, have the battery checked,to see whether it needs to be charged or replaced.

mmaddox · mmaddox's Garage

The day my car got to Bend, the CDI box was the issue. Did exactly the same thing.

OttoBob · 06-02-2013, 07:56 PM

I just got the Bentley manual, so I will follow the steps for ignition system quick check as soon as I can get a spark plug and a helper. I did test for primary voltage at the ignition coil, and got 12.42 volts. I will keep it on the battery tender until then. Any other ideas?

DRACO A5OG · DRACO A5OG's Garage

DME relay is under driver seat

OttoBob · 06-02-2013, 08:05 PM

mmadox, Is the CDI box the same as the DME box for an earlier car?

DRACO A5OG · DRACO A5OG's Garage

Nope

timmy2 · timmy2's Garage

OttoBob,
Just happens I'll be in Redmond on business for 3 nights starting tomorrow.
If you need a helper PM me your phone number for tomorrow night.

theiceman · 06-03-2013, 05:31 AM

...er guys ..... his car is not even turning over ... forget dme, and all that crap ..

check battery connections and ground connections ( dont forger the big one under neath that grounds the transmision to the body via the crossmember under the gear box. .. check connection at starter motor . if a jump from another car doesnt get it to turn over suspect your starter motor or connections..

Quicksilver · 06-03-2013, 07:22 AM

Quote:

Originally Posted by theiceman

...er guys ..... his car is not even turning over ... forget dme, and all that crap ..

check battery connections and ground connections ( dont forger the big one under neath that grounds the transmision to the body via the crossmember under the gear box. .. check connection at starter motor . if a jump from another car doesnt get it to turn over suspect your starter motor or connections..

+1

Time to break out the multimeter. Need to see if putting the key to start means that there is 12 volts at the solenoid. If there is 12V on the wire to the solenoid then the issue is the starter/solenoid or possibly the battery cable/connection (not as likely).
If there isn't voltage to the solenoid then the problem is in the circuit leading to the starter. Maybe the switch. If there is an alarm that needs to be checked, wires, etc...

rick-l · 06-03-2013, 07:36 AM

Quote:

Originally Posted by OttoBob

No cranking at all. A small hum.

A small hum like a fuel pump or a small hum like the starter spinning?

theiceman · 06-03-2013, 01:33 PM

... or a small hum like a starter solenoid stuck ? .. et under and whack it with a screwdriver handle see if it starts .,...

Good call on the alarm BTW never thought of that ..

OttoBob · 06-03-2013, 02:13 PM

The small hum is more like an electrical whine like a pump and seems to be coming from the front of the car. I will try tapping on the starter solenoid, as soon as I can locate the starter!

DRACO A5OG · DRACO A5OG's Garage

Starter is at the passenger rear wheel well.

Before you start tapping at it, check the voltage at the starter per Bentley, this will tell you if yo have enough voltage to turn the starter over.

OttoBob · 06-03-2013, 04:57 PM

Problem diagnosed...I assume. 12.60 volts at the starter solenoid. Tapped on the solenoid. Car started fine. Shut off ignition, attempt restart - no start. What should be replaced/repaired? Thanks folks for the help!

Quicksilver · 06-03-2013, 05:17 PM

The fact that the Bosch starter solenoids are sealed so you can't open them for servicing really pisses me off. Usually a solenoid failure is simply erosion of the copper contacts that are at the other end of the two large threaded studs that the starter and battery cable connect to. Child's play to fix (turning them 180° will get another life out of them) but sealed units makes them an expensive replacement instead...