Intermittent start
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From: Coos Bay, Oregon
Intermittent start
My car is a 1980 Euro 928S, 5-speed. I've done a search and have found some possibilities from 2002 yr. posts. I'm hoping to get some ideas together to give my mechanic (Porsche dealer, Charlotte, NC).
After driving a while, such as today's 65 mile return from the shop, and turning off the engine, the bugger won't start. All the dash lights work. No click to be heard. After cooling down, she started right up. However, in the past, she wouldn't start even when cooled down. (Same driving scenario.) Brand new battery. Contacts at the starter freshly cleaned. Always 93 octane fuel. Can roll start (reverse), quick shut down (to turn off the dash lights), and restart with key.
Two possibilities I've noted:
Replace electrical starter switch solenoid. Napa#MPEST81SB
Replace ignition switch electrical.
Please keep in mind I'm a musician not a mechanic.
Any more suggestions? Anyone know of someone in the overall Charlotte, NC/Greenville, SC area who is REALLY good with a Euro 928S?
Many thanks in advance.
Geoffrey
After driving a while, such as today's 65 mile return from the shop, and turning off the engine, the bugger won't start. All the dash lights work. No click to be heard. After cooling down, she started right up. However, in the past, she wouldn't start even when cooled down. (Same driving scenario.) Brand new battery. Contacts at the starter freshly cleaned. Always 93 octane fuel. Can roll start (reverse), quick shut down (to turn off the dash lights), and restart with key.
Two possibilities I've noted:
Replace electrical starter switch solenoid. Napa#MPEST81SB
Replace ignition switch electrical.
Please keep in mind I'm a musician not a mechanic.
Any more suggestions? Anyone know of someone in the overall Charlotte, NC/Greenville, SC area who is REALLY good with a Euro 928S?
Many thanks in advance.
Geoffrey
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From: Ball Ground, GA
Geoffrey,
One standard problem with long-distance guessing is the imprecise language for a no-start condition.
"The engine won't start," is very uninformative.
"The starter doesn't spin the engine," OR "The engine turns over at normal speed, but doesn't fire," are both informative statements.
"No click to be heard." That tends to make me thing that the starter is totally nonfunctional when the engine is hot.
The lack of a clack makes me suspect the starter triggering circuit.
Power flows from terminal 50 on the ignition switch to terminal A6 (second terminal up on the right row of the first plug on the left at the bottom of the central power panel).
The power flows internally to terminal 30 in the socket where Relay XIV would be installed on an automatic. A brass jumper bar carries the power to terminal 87, and from there the power flows to terminal O5.
From O5, a yellow wire runs to the cluster of wires at the jump start terminal on the right fender panel. The power flows thru T14 in the large connector there, and then down to the starter solenoid to trigger the starter.
The first suggestion is to carefully check and clean the cluster of wires at the jump start terminal - especally, of course, the yellow wire.
If that doesn't cure the problem, you may need to hook a test light at various points in the circuit to check for where you are losing the power.
One standard problem with long-distance guessing is the imprecise language for a no-start condition.
"The engine won't start," is very uninformative.
"The starter doesn't spin the engine," OR "The engine turns over at normal speed, but doesn't fire," are both informative statements.
"No click to be heard." That tends to make me thing that the starter is totally nonfunctional when the engine is hot.
The lack of a clack makes me suspect the starter triggering circuit.
Power flows from terminal 50 on the ignition switch to terminal A6 (second terminal up on the right row of the first plug on the left at the bottom of the central power panel).
The power flows internally to terminal 30 in the socket where Relay XIV would be installed on an automatic. A brass jumper bar carries the power to terminal 87, and from there the power flows to terminal O5.
From O5, a yellow wire runs to the cluster of wires at the jump start terminal on the right fender panel. The power flows thru T14 in the large connector there, and then down to the starter solenoid to trigger the starter.
The first suggestion is to carefully check and clean the cluster of wires at the jump start terminal - especally, of course, the yellow wire.
If that doesn't cure the problem, you may need to hook a test light at various points in the circuit to check for where you are losing the power.
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I have 79. The starter was changed twice by the PO to try to solve the warm no start problem. I ended up installing an interposing relay (Ford part) on the starter circuit to make it work. See a post by Randy V on this subject. He has a wiring diagram showing where the relay is installed.
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From: Insane Diego, California
Ah, nice to see that helped you, Sean.
This may help if you don't discover an alternative fix Geoffrey:
No Start When Hot Fix
This may help if you don't discover an alternative fix Geoffrey:
No Start When Hot Fix
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From: Coos Bay, Oregon
Hi,
Wally: Sorry to be imprecise. "Won't start" is meant as no starter activation, no engine turning over, no cranking of any type. No sound of anything happening whatsoever other than the dash buzzer. Dead silence other than the aforementioned buzzer. I'll inspect and clean as per your info.
Randy V: Thanks for the link. The prior link that I'd located was no longer valid.
Keep the ideas coming folks. 928s are not Hendrick Porsche's forte.
Much appreciated,
Geoffrey
Wally: Sorry to be imprecise. "Won't start" is meant as no starter activation, no engine turning over, no cranking of any type. No sound of anything happening whatsoever other than the dash buzzer. Dead silence other than the aforementioned buzzer. I'll inspect and clean as per your info.
Randy V: Thanks for the link. The prior link that I'd located was no longer valid.
Keep the ideas coming folks. 928s are not Hendrick Porsche's forte.
Much appreciated,
Geoffrey
