starter problem- again- lost- please help

gchappel · 10-26-2002, 10:13 AM

I have had an intermittent starter problem that has me at wits end. One main problem is my mechanic is 55miles away- it usually is a flatbed tow to get the car too him as I can't take a day off work. The car is an 85 row carrera- that has been very reliable for the last 3 years.
The problem is very intermittently you turn the key- and no starter- fuel pump runs- but no starter at all. First time was about a year ago- flatbedded car to mechanic- when it got there it worked fine. He went through everything- checked the ignition switch, no power loss through the wire loom, starter ok, battery ok, etc. So $700 later I get the car back and it works for 8months- then same thing. This time I tapped the solenoid with a hammer- and it worked for 4 more months. The third time it happened I tapped the solenoid again- it started up- and I took it to the mechanic. When the car got there it would not start. He put in a new starter- same problem. He tried a 3rd starter- same thing. The battery measured a little low- so he tried jumping the car - and the starter worked fine. We didn't know what to do- so I left the new starter-which is a rebuilt stock starter- in, and put in a new battery. Car ran fine for 2 weeks- now same thing again. Where do I go from here? I have power to the starter, a new battery, a new starter, the ignition switch was just checked. I am considering adding one of those relays that bypass some of the wiring to the solenoid- but I don't like bandaid repairs. I would appreciate any ideas on what to do next- besides set the car on fire, or always park on a hill so I can push start it. Is there a way I can jump power to the small solenoid lead to see if that is the problem?? The basic stuff, like the ground strap on the transmission is ok.
Thanks
gary

AZ1977911 · 10-26-2002, 10:28 AM

Hi jchappel,

I had the same problem with the same symptoms. I replace the starter twice (with non Bosch), did not fix the problem. My wrench said the problem is common and the fix is simply to replace the starter with a new Bosch. I said go ahead what I did wasnt working. He put a new Bosch in and the problem is solved. I have heard that the HiTorque starters work as well, but have no experience with those.

Hope this helps.

gchappel · 10-26-2002, 11:45 AM

One new fact:
Voltage from battery- 12.9V
Voltage at main lead at starter-12.9V
Voltage at "solenoid" lead when the key is turned to start postion-9.4V
I assume this type of voltage drop is my problem. I know the loss could be at the ignition switch, or loss along the wire. Any thoughts- or is the relay addition the easy fix here?? How do I proceed from here?
Can I safely run a jumper from the main lead at the starter to the solenoid lug just to test my idea- or will that short something out??

Thanks again
Gary

marcesq · marcesq's Garage

Gary:

You can bridge the Battery lead to the solenoid without harming anything (that is how remote starter switches work). removed the DME relay and tap it gently with the butt end of a screw driver, and replace.

Also check the ground strap from the trany to the chassis.

Good luck, electrical gremlins are the pits.

Rouxzy · 10-26-2002, 01:35 PM

I had the same problem, change out a few things but found through trial and error that it was the alternator. Get the car started and check the voltage at the battery. It should be above, if I remember right above 14 volts. If not then either the alt is not working right or you got a big draw. With me the alt would work sometimes so the battery would be charged enough to run but then a few weeks later the alt wouldn't charge and the battery would run down enough so that it wouldn't start. The fuel pump, lights and everything else would work but no starter. You need the full 12+ volts to start it. I hope this helps.

gchappel · 10-26-2002, 02:30 PM

OK, continued work in progress.
I ran a wire from the hot lead at the starter to the solenoid lead- nothing.
I then ran a jumper cable from the positive of my battery, back to the starter- car started right up. Now it works normally- gosh I hate these intermittent gremlins. Does this sound like I need to run a new power cable to the starter- don't know how hard that would be to do- or would the starter relay help with this?????
Thanks again, I am kind of at wits end.
Gary

scottb · 10-26-2002, 02:34 PM

Here's a thought straight out of left field (which is appropriate considering that the World Series starts in about an hour) -- Is it possible you have a problem with the starter switch?

RoninLB · 10-26-2002, 04:27 PM

Quote:

Originally posted by gchappel
Voltage at "solenoid" lead when the key is turned to start postion-9.4V
I assume this type of voltage drop is my problem. I know the loss could be at the ignition switch, or loss along the wire. Any thoughts- Gary [/B]

Gary...9.4V doesn't read too good..in fact it's bad..so, you gotta fix that voltage drop...sorry, can't say what's happening because you got a start from a direct feed from bat to starter..maybe 2 problems..if it was my problem I would install a temporary sol jump from starter using a relay..trigger relay only when a problem..and check voltage drop at bat positive and starter when cranking eng with ignition disconnected........Ron

rstoll · 10-26-2002, 04:32 PM

I cleared up my intermittent starter problems by cleaning the 14 pin connector in the engine compartment. Clean, spread the male terminals with a single edge razor blade and coat with dielectric silicone. Good luck.

gchappel · 10-26-2002, 05:04 PM

rstolll- where is the connector??

Is there a lead anywhere in the rear of the car/engine compartment where I can pick up an additional high current lead to go to the starter, or do I need to pull a line from the battery itself? Any ideas on how to pull the line from the battery- sorry to sound so dumb, but I am- do I run the lead under the car, in the tunnel, or what? The wiring will be easy, but pulling an additional lead looks like a difficult project unless I just run it under the car.
Thanks again.
Gary

RoninLB · 10-26-2002, 05:47 PM

Gary..there is a bunch of connectors from the starter switch to starter sol...the yellow wire has a connection in the under dash area of luggage compartment on driver side..if you have a starter disable on an alarm system chances are the disable relay has a smaller diameter feed wire to the yellow sol feed/may be contributing to problem along with this relay..in your engine comp on the driver side close to the electrical panel is the 14 pin connector..and I shouldn't forget the electrical part of the ignition switch, which I believe should be changed at 100k miles/neurotically speaking, if only for preventive maintance..I would still connect a temporary 30 amp relay to starter to get the car back on the road and spend hours cleaning up things later..and the issue with a battery jumper cable to starter that you did for a start..the battery positive connector is a possibility along with the 2 smaller red feed wires/the connection is not bulletproof...of course you cleaned the chassis ground foreward of the battery and the tranny to chassis ground.........Ron

rstoll · 10-26-2002, 05:47 PM

It is located on the back of the relay/fuse block on drivers side of engine compartment wall. Clean the plug, no rewiring necessary.

rstoll · 10-26-2002, 05:49 PM

btw, also fixed my jumpy oil pressure guage by tightening/cleaning connection at sending unit. I like those easy repairs.

Chad Ruwe · 10-27-2002, 04:50 PM

I don't want to step on any toes here.....seeing as this is my first post as a technicial issue. If we know the solenoid is getting only 9.4 volts, then obviously the problem is somewhere between the Pos. post at the battery and the start wire at the solenoid ( given that the starter has a good clean ground) Using a voltmeter, put the black wire on the POS post and the red wire on the start wire wire at the solenoid. With the key in the start position the meter should be less than .4 volts anything above that indicates that the system has a weak connection and or weak wire. The next test is very simple and works on any circuit. Going backwards from the solenoid connect the red wire to the other end of the start wire and check for a voltage drop. Continue on through the system ( backwards ) until you have LESS than .4 volts and there is the problem area. Also do the same test on the ground side at the starter. Just remember........the circuit HAS TO HAVE AN APPLIED LOAD!!!!! As in, if working with the headlamp circuit......turn the headlamps on!!!!!! As a hint........correct voltage through the ign switch has been a problem on every make and model vehicle out there!!!!!

RoninLB · 10-27-2002, 04:56 PM

I'm with Chad on this one..............Ron

gchappel · 10-27-2002, 05:15 PM

Thanks, I'll start through the system with this in mind. Does anyone know where all I need to check? I believe there is a connection at the 14pin plug in the engine compartment, there is of coarse the connection at the ignition switch itself, and I believe a connection in the trunk, or luggage compartment- any other places to check?
Does the wire stay yellow throughout the car?- I can find it with a continuity checker- but color would be easier?
I will also add an additional ground strap to the starter- and hopefully I will have my reliable everyday driver back again
thanks- this board is great
Gary

Chad Ruwe · 10-27-2002, 05:40 PM

Can anyone send me the starter circuit wiring for the car in question ...I would LOVE to help!

I'm a little lost on this whole idea of adding a SECOND ground. Over the years I've learned several important phrases most have heard
The wheel will always be round.
If it ain't broke.........you know the rest !!!! and
Do like the military does, if it ain't broke fix it untill it is!!!!

My point is why not just do the voltage drop test on the system and find the actual problem. If you have no voltage drop on the ground side than a second ground will give you the exact same reading.
Man...I'm not chewing on ya .....I just hate to see a fellar work up a headache on a problem that's very rewarding to you when the problem is found. Current flow is like water.. If you install a dam in the system, it may not stop all of the water but is sure as hell slows it down!!!!! HHHMMMMM....almost like a bad connection!!!!!!
PS: I only use ONE toothbrush....it works just fine

RoninLB · 10-27-2002, 06:29 PM

[QUOTE]Originally posted by Chad Ruwe
[B]Can anyone send me the starter circuit wiring for the car in question ...I would LOVE to help!

I'm a little lost on this whole idea of adding a SECOND ground

Chad...I'm sorry for any confusion on the 2nd ground..it's not generally necessary..not many do a 2nd ground..I have added a 2nd ground because I want a back-up to the stock ground..I do BigBig Rides in the 911, and IMO the 911 electrical system leaves much room for improvement. wait till you want to install real high watt headlights into a stock 911 headlight system..I can't be trouble shooting an electrical system weakness in the remote areas I travel to..and you may be correct "if it ain't broke", but I don't have that luxury..and for reference, Early S Man has the most logical approach to 911 electrical systems/ not me ..
Pelican has wiring diagrams somewhere on this web..........Ron

autobonrun · autobonrun's Garage

Quote:

Originally posted by Chad Ruwe
Can anyone send me the starter circuit wiring for the car in question ...I would LOVE to help!

Here's a circuit from this site. You'll need to access page 1 and 2 for the starter circuit.

http://www.pelicanparts.com/911/911_Parts/Electrical/911_electrical_82SC_Part1-1.jpg

Superman · 10-27-2002, 09:28 PM

Ahem. Any car that is the age of our cars could use a thorough cleaning of all electrical contacts and connections. Electrical gremlins are caused by dirty connections more often than all other causes combined, I think. That 9.6 volts thing is almost certainly being caused by corrosion somewhere. Every chance you get, unplug connections, wire brush them, apply a tiny bit of silicon grease and reconnect.