Need help
Thread Starter
AutoX
Joined: Nov 2010
Posts: 13
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Need help
Hey,
Im in need of help again
My 1980 Porsche 928S V8 auto sometimes starts, majority of the time it doesent
Also the positive terminal of the battery and the wire corrodes everytime and also its sometimes randomly flat.
Can anyone help me out?
Cheers,
Patrick.
Im in need of help again
My 1980 Porsche 928S V8 auto sometimes starts, majority of the time it doesent
Also the positive terminal of the battery and the wire corrodes everytime and also its sometimes randomly flat.
Can anyone help me out?
Cheers,
Patrick.
Rennlist Member
Joined: Nov 2004
Posts: 5,243
Likes: 1,043
From: DFW Texas
I'm no electrical expert, but battery wires corrode because of excessive battery fumes. Is your battery vented properly? Have you checked the charging rate when the car is running, the regulator may be overcharging the battery causing the excessive fumes? Are you replacing the positive wire or just cleaning it? Has the corrosion gotten under the insulation and up the strands of wire? That will cause excessive resistance.
Do you have excessive battery drain when everything is off? A stuck relay or a light that is staying on all the time even if intermittent will cause the battery to become flat in a short period of time.
Do you have excessive battery drain when everything is off? A stuck relay or a light that is staying on all the time even if intermittent will cause the battery to become flat in a short period of time.
Rennlist Member
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Joined: Jun 2001
Posts: 6,469
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From: Ball Ground, GA
As Jim says, sounds as if you have a voltage problem, venting problem, or a faulty battery.
That MIGHT be causing the no-start problem - or might not be. Time for some basic troubleshooting.
- Does the fuel pump run while the starter is spinning?
- What does the tach do while the starter is spinning?
- Do the injectors click while the starter is spinning?
- Do you have spark while the engine is spinning?
No magic answers, just things that the only person who can see the car must check...
That MIGHT be causing the no-start problem - or might not be. Time for some basic troubleshooting.
- Does the fuel pump run while the starter is spinning?
- What does the tach do while the starter is spinning?
- Do the injectors click while the starter is spinning?
- Do you have spark while the engine is spinning?
No magic answers, just things that the only person who can see the car must check...
Thread Starter
AutoX
Joined: Nov 2010
Posts: 13
Likes: 0
I'm no electrical expert, but battery wires corrode because of excessive battery fumes. Is your battery vented properly? Have you checked the charging rate when the car is running, the regulator may be overcharging the battery causing the excessive fumes? Are you replacing the positive wire or just cleaning it? Has the corrosion gotten under the insulation and up the strands of wire? That will cause excessive resistance.
Do you have excessive battery drain when everything is off? A stuck relay or a light that is staying on all the time even if intermittent will cause the battery to become flat in a short period of time.
Do you have excessive battery drain when everything is off? A stuck relay or a light that is staying on all the time even if intermittent will cause the battery to become flat in a short period of time.
How can i check the charging rate while the car is running?
Just cleaning the positive wire and yes the corrosion is under and up the strands of the wire
About the battery drain yes when i take the car out for a drive a few days after the battery is flat so i have to jump start it.
Also lets say i go for a hour or so drive to visit someone, leave the car their for a few hours, the car wont crack the starter motor even though the battery isnt flat.
As Jim says, sounds as if you have a voltage problem, venting problem, or a faulty battery.
That MIGHT be causing the no-start problem - or might not be. Time for some basic troubleshooting.
- Does the fuel pump run while the starter is spinning?
- What does the tach do while the starter is spinning?
- Do the injectors click while the starter is spinning?
- Do you have spark while the engine is spinning?
No magic answers, just things that the only person who can see the car must check...
That MIGHT be causing the no-start problem - or might not be. Time for some basic troubleshooting.
- Does the fuel pump run while the starter is spinning?
- What does the tach do while the starter is spinning?
- Do the injectors click while the starter is spinning?
- Do you have spark while the engine is spinning?
No magic answers, just things that the only person who can see the car must check...
The tach is normal
Yes the injecters click while the starter is spinning
Yes i have a spark while the engine is spinning
Cheers,
Patrick.
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Joined: Jun 2001
Posts: 6,469
Likes: 13
From: Ball Ground, GA
Patrick,
No offense intended, but "My car won't start" is virtually meaningless. Much more informative, and much more likely to get the correct answers would be one of these statements.
When I turn the key to start, the starter doesn't spin. No noise, no clicks, nothing.
When I turn the key to start, the starter spins normally, but the engine doesn't start.
Very different problems, very different answers. It is very difficult to give too much information when asking for help...
One indication of whether charging is correct is the system voltage, which should be somewhere between 13.2 - 14.6 vdc with the battery charged and the engine above 1500 rpm. If the battery is very low, the system voltage will normally be toward the lower value, when fully charged, toward the higher value.
A failing battery generates more corrosive fumes. An overcharged battery generates more corrosive fumes. Some batteries have vent tubes that go out of the battery box thru rubber grommets.
It sounds as if you have done some cleaning of battery connections. Make sure that all of the connections are clean - dull gray metal is not clean. If the battery terminals feel crunchy when you scrape them with a knife, they are corroded. Do both ends of the ground strap. Any warmth on any connection is an indication of a poor connection.
If the battery caps can be removed, fill with distilled water to the rings. If the caps can't be removed, you just discovered that "maintenance free" doesn't mean that it doesn't go bad, it just means that you can't do anything about it.
Most parts stores can check the battery. Charge it (every 928 owner eventually needs a charger or maintainer) and carry it to at least two different stores for testing.
No offense intended, but "My car won't start" is virtually meaningless. Much more informative, and much more likely to get the correct answers would be one of these statements.
When I turn the key to start, the starter doesn't spin. No noise, no clicks, nothing.
When I turn the key to start, the starter spins normally, but the engine doesn't start.
Very different problems, very different answers. It is very difficult to give too much information when asking for help...
One indication of whether charging is correct is the system voltage, which should be somewhere between 13.2 - 14.6 vdc with the battery charged and the engine above 1500 rpm. If the battery is very low, the system voltage will normally be toward the lower value, when fully charged, toward the higher value.
A failing battery generates more corrosive fumes. An overcharged battery generates more corrosive fumes. Some batteries have vent tubes that go out of the battery box thru rubber grommets.
It sounds as if you have done some cleaning of battery connections. Make sure that all of the connections are clean - dull gray metal is not clean. If the battery terminals feel crunchy when you scrape them with a knife, they are corroded. Do both ends of the ground strap. Any warmth on any connection is an indication of a poor connection.
If the battery caps can be removed, fill with distilled water to the rings. If the caps can't be removed, you just discovered that "maintenance free" doesn't mean that it doesn't go bad, it just means that you can't do anything about it.
Most parts stores can check the battery. Charge it (every 928 owner eventually needs a charger or maintainer) and carry it to at least two different stores for testing.
Race Director
Joined: Sep 2007
Posts: 12,162
Likes: 383
From: Johnson City, TN
Patrick,
In something like your first or second post we suggested that you get the shop manuals and you asked what shop manuals were.
You will need the shop manuals, electronically at least, which include the wiring diagrams and some significant inclination to dive into them if you want to drive a 31 year old car. Not a lot of support in such a big country as yours for these cars, so even a wad of cash won't help.
If nothing else, it will help you narrow your questions. Like Wally indicates, and he is a true guru on these cars, there are dozens of things that can go wrong and its up to you to give enough information to help us help you if you need help. Else just sell it and save yourself the trauma.
In something like your first or second post we suggested that you get the shop manuals and you asked what shop manuals were.
You will need the shop manuals, electronically at least, which include the wiring diagrams and some significant inclination to dive into them if you want to drive a 31 year old car. Not a lot of support in such a big country as yours for these cars, so even a wad of cash won't help.
If nothing else, it will help you narrow your questions. Like Wally indicates, and he is a true guru on these cars, there are dozens of things that can go wrong and its up to you to give enough information to help us help you if you need help. Else just sell it and save yourself the trauma.
Thread Starter
AutoX
Joined: Nov 2010
Posts: 13
Likes: 0
When the car is on, you can hear the flasher relay clicking underneath even though the indicaters are being used, What would be the cause of this?
Hey,
Sorry about the dumbness.
I totally forgot about the shop manuals.
The thing is the car isnt mine, its my dads and im just trying to help him out
Thanks for the heads up
Patrick,
In something like your first or second post we suggested that you get the shop manuals and you asked what shop manuals were.
You will need the shop manuals, electronically at least, which include the wiring diagrams and some significant inclination to dive into them if you want to drive a 31 year old car. Not a lot of support in such a big country as yours for these cars, so even a wad of cash won't help.
If nothing else, it will help you narrow your questions. Like Wally indicates, and he is a true guru on these cars, there are dozens of things that can go wrong and its up to you to give enough information to help us help you if you need help. Else just sell it and save yourself the trauma.
In something like your first or second post we suggested that you get the shop manuals and you asked what shop manuals were.
You will need the shop manuals, electronically at least, which include the wiring diagrams and some significant inclination to dive into them if you want to drive a 31 year old car. Not a lot of support in such a big country as yours for these cars, so even a wad of cash won't help.
If nothing else, it will help you narrow your questions. Like Wally indicates, and he is a true guru on these cars, there are dozens of things that can go wrong and its up to you to give enough information to help us help you if you need help. Else just sell it and save yourself the trauma.
Sorry about the dumbness.
I totally forgot about the shop manuals.
The thing is the car isnt mine, its my dads and im just trying to help him out
Thanks for the heads up