Starter/Alternator issue?
Thread Starter
Drifting
Joined: Feb 2010
Posts: 1,394
Likes: 19
From: Levittown NY
Starter/Alternator issue?
I’ve had a weird problem the last two weekends. Went out for ride last week, got stuck in traffic for a while, when I parked the car, went out shopping, and came back started car up and I see the alternator was not charging. Rushed home before car would die and parked in driveway. A couple of hours later I go out and start car, voltage was at 14.2. Next day I start car voltage was at 14.7.
Took car out today, voltage started out normal, drove around for about a half an hour, parked, got out, did some shopping, came back started the car, I get low voltage again. I get home, let car sit for awhile, start it, low voltage. Car has a Mechman alternator, figured I would swap it out with my OEM one. Put old one in, start it up, low voltage. I shut car, start again and voltage was over 14. I put voltmeter at alternator, was around 14.5, voltage at battery and fuse box was 13.5. Put car on ramps, check wires at starter, they were tight, but when I pushed them I could see the terminal move ever so slightly. Would this mean solenoid is on its way out? Starter is 2 years old, car has headers.
What do you think?
Took car out today, voltage started out normal, drove around for about a half an hour, parked, got out, did some shopping, came back started the car, I get low voltage again. I get home, let car sit for awhile, start it, low voltage. Car has a Mechman alternator, figured I would swap it out with my OEM one. Put old one in, start it up, low voltage. I shut car, start again and voltage was over 14. I put voltmeter at alternator, was around 14.5, voltage at battery and fuse box was 13.5. Put car on ramps, check wires at starter, they were tight, but when I pushed them I could see the terminal move ever so slightly. Would this mean solenoid is on its way out? Starter is 2 years old, car has headers.
What do you think?
Race Director
Joined: Dec 2002
Posts: 10,468
Likes: 1,149
From: Wayne Township WI
Solenoid failures, ESPECIALLY w/ headers if both headers and starter aren't heat wrapped, aren't unusual.
Seems much more common w/ car's in 'hot' climate, so where do you live?
Should be no movement on solenoid posts and if there is it may indicate bakelite cracked.
If solenoid checks out, might be alternator's in the process of failing, ergo, intermittent performance/behavior.
Those 2 items have to be thoroughly checked and ruled out as a cause.
Race Director
Joined: Dec 2013
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Headers, no heat protection on the starter solenoid , would bank that you have a cap that the terminal is start to crack off.
So new starter solenoid to replace on your starter is about $20, and you can pick up starter solenoid heat shields for about $20 that only take a little moding to work.
As for your alternator )it body as ground, and back terminal under the rubber boot as positive), should be putting out about 14.7 volts as the car is idling, lights off, and radiator fan not spinning. If the voltage in these conditions is less than this, would start to check the fuses in the fuse box that send reference voltage to the alternator to being with (horn fuse is one of them). So alternator at 14.7, battery down line in same condition should be around 14.5 volts.
So new starter solenoid to replace on your starter is about $20, and you can pick up starter solenoid heat shields for about $20 that only take a little moding to work.
As for your alternator )it body as ground, and back terminal under the rubber boot as positive), should be putting out about 14.7 volts as the car is idling, lights off, and radiator fan not spinning. If the voltage in these conditions is less than this, would start to check the fuses in the fuse box that send reference voltage to the alternator to being with (horn fuse is one of them). So alternator at 14.7, battery down line in same condition should be around 14.5 volts.
Thread Starter
Drifting
Joined: Feb 2010
Posts: 1,394
Likes: 19
From: Levittown NY
I followed a post you had made a while back on what to check. The fact that swapping out alternator resulted in the same issue made it easier to diagnose.without buying parts that would have resulted in an unsolved problem. I live in NY, and probably have not put on 5000 miles on the car in the past 2 years!
Last edited by gp56; Jul 12, 2020 at 05:21 PM.
Thread Starter
Drifting
Joined: Feb 2010
Posts: 1,394
Likes: 19
From: Levittown NY
2006.i swapped out alternators, issue persisted. Seems that when car cools down everything seems normal. Wondering if something is expanding when it heats up and then the electrical connection at starter fails. Will contact my mechanic this week to inspect starter further.
Race Director
Joined: Dec 2002
Posts: 10,468
Likes: 1,149
From: Wayne Township WI
Recall C6 fuse blocks replaced under recall?
Power line feeding low beams due to expansion/contraction cracked causing an open. No low beams.
Here again though problem was much more prevalent in hotter climates w/ more extreme temp fluctuations.
Could manifest today in northern tier climates, not due to heat though -- age.
