Is this a ground problem??? - HELP!!
Thread Starter
Addict
Rennlist Member
Rennlist Member
Joined: Jan 2003
Posts: 3,537
Likes: 1
From: Mountains of GA!
Is this a ground problem??? - HELP!!
Ok...so about a week ago, intermittantly at idle - she starts doing the instrument 'dance'....Tach bounces around 0, and the other gauges start moving up and down....A little throttle would bring everything back to normal...and sometimes everything would be fine at idle....sometimes not...
Went to the store, inside 5 minutes - came out....battery acted dead...walked home (thank goodness it was close) - got the truck and went back and used the battery cables...and after some fairly lengthy cranking - she finally fired up...but - would sound like it had a dragster cam at idle, and die after about 10 seconds...
Came back home and got the trailer - thankfully saw a friend in the parking lot - so I was able to set up the trailer - battery jump off of their vehicle - and manage to keep it running...ONLY by keeping the revs up over 2000...
I seem to racall a similar recent thread - but can't find it.
HELP!!
Went to the store, inside 5 minutes - came out....battery acted dead...walked home (thank goodness it was close) - got the truck and went back and used the battery cables...and after some fairly lengthy cranking - she finally fired up...but - would sound like it had a dragster cam at idle, and die after about 10 seconds...
Came back home and got the trailer - thankfully saw a friend in the parking lot - so I was able to set up the trailer - battery jump off of their vehicle - and manage to keep it running...ONLY by keeping the revs up over 2000...
I seem to racall a similar recent thread - but can't find it.
HELP!!
Addict
Rennlist Member
Rennlist Member
Joined: Jul 2002
Posts: 383
Likes: 1
From: St. John's, NF, Canada
Mark;
I think the thread you might be refering to is one about an '85 Euro stalling at the most inopertune time. Here's the link to that one.
https://rennlist.com/forums/showthre...threadid=82856
Not sure if the definitive answer was find on that one, but I believe the problem was connected to the ignition switch. Yours could be too. Sounds like you have an electrical-related problem rather than a fuel-related one to me.
Someone suggested checking the connector on the rear of the ignition switch...it may simply be loose. The ignition switch is the one part of the car that could clearly effect spark, fuel and electrical to the instruments...but there are no doubt other things that could cause the problem you are experiencing. Try wiggling the key while the car is running too...that might help (what am I saying!!!).
You might be able to get at the connector on the back of the ignition stalk either by removing the trim panel on the bottom of the pod or by simply raising the pod all the way up. On my car I can get my (admittedly small) hand up near the switch with a combination of these things. You could even unbolt the pod bolts on the right-hand side to give some more room. Just be careful whatever you do...would not want you to crack the instrument cluster of something!
Regards,
SteveCo in St. John's
I think the thread you might be refering to is one about an '85 Euro stalling at the most inopertune time. Here's the link to that one.
https://rennlist.com/forums/showthre...threadid=82856
Not sure if the definitive answer was find on that one, but I believe the problem was connected to the ignition switch. Yours could be too. Sounds like you have an electrical-related problem rather than a fuel-related one to me.
Someone suggested checking the connector on the rear of the ignition switch...it may simply be loose. The ignition switch is the one part of the car that could clearly effect spark, fuel and electrical to the instruments...but there are no doubt other things that could cause the problem you are experiencing. Try wiggling the key while the car is running too...that might help (what am I saying!!!).
You might be able to get at the connector on the back of the ignition stalk either by removing the trim panel on the bottom of the pod or by simply raising the pod all the way up. On my car I can get my (admittedly small) hand up near the switch with a combination of these things. You could even unbolt the pod bolts on the right-hand side to give some more room. Just be careful whatever you do...would not want you to crack the instrument cluster of something!
Regards,
SteveCo in St. John's
Rennlist Member
Joined: Aug 2001
Posts: 502
Likes: 0
The above are very good suggestions; I'd just throw one more thing into the mix.
I had a very similar problem - subject of a long thread - that degenerated into a complete no-start/no run over time. After chasing everything under the sun, it finally turned out to be a distributor that was going bad (excessive wear/endplay). Played hell with the tach and the running.
Might be worth looking at - if your '85 Euro has the same ignition system as my '83US, I can give you my diagnostic write-up for testing.
Good luck.
I had a very similar problem - subject of a long thread - that degenerated into a complete no-start/no run over time. After chasing everything under the sun, it finally turned out to be a distributor that was going bad (excessive wear/endplay). Played hell with the tach and the running.
Might be worth looking at - if your '85 Euro has the same ignition system as my '83US, I can give you my diagnostic write-up for testing.
Good luck.
Trending Topics
Thread Starter
Addict
Rennlist Member
Rennlist Member
Joined: Jan 2003
Posts: 3,537
Likes: 1
From: Mountains of GA!
Thanks for the suggestions...Joe - No alarm on my euro...James - I really don't think it is the distributors. I pulled the caps and all seems as it should...and the '85 has twins...Also did a limited inspection of the connector and wiring harness behind the jump start terminal.
I think I've narrowed it down to the alternator....maybe
Per Wally - I went thru and checked/cleaned all the grounds...pulled pod and cleaned all the connections (gave me the chance to finally adjust my speedo that was always 6mph low...from when I put the needle on wrong when I replaced the gear a while back)...swapped around some of the relays that are the same...even installed a new battery...started and runs fine...but all the warning lights still come on when first started up, until I rev it up for a few seconds. (This is different from the 'all the warnings on' when you first turn on the key - they stay lit when the car is started, until the engine is revved over 2000 for a few seconds)
Here's why I think it may be the alt...BUT - I admit I have been WRONG in my life on more than a few occassions!
If it is not charging properly, as the battery slowly lost power - there was not adequate voltage for everything...especially at idle - thus the warning lights. I'll go out and dog it today at the AX (even tho it's only 20 miles from home - I'll trailer it today...AND keep the jumper cables in the truck!) and pull the alternator one night this week.
UNLESS - there are any more ideas/opinions.
I think I've narrowed it down to the alternator....maybe
Per Wally - I went thru and checked/cleaned all the grounds...pulled pod and cleaned all the connections (gave me the chance to finally adjust my speedo that was always 6mph low...from when I put the needle on wrong when I replaced the gear a while back)...swapped around some of the relays that are the same...even installed a new battery...started and runs fine...but all the warning lights still come on when first started up, until I rev it up for a few seconds. (This is different from the 'all the warnings on' when you first turn on the key - they stay lit when the car is started, until the engine is revved over 2000 for a few seconds)
Here's why I think it may be the alt...BUT - I admit I have been WRONG in my life on more than a few occassions!
If it is not charging properly, as the battery slowly lost power - there was not adequate voltage for everything...especially at idle - thus the warning lights. I'll go out and dog it today at the AX (even tho it's only 20 miles from home - I'll trailer it today...AND keep the jumper cables in the truck!) and pull the alternator one night this week.
UNLESS - there are any more ideas/opinions.
Rennlist Stories
The Best Porsche Posts for Porsche Enthusiasts
9 Features and Characteristics That Only Porsche People Understand
Verdad Gallardo
I've Written 500 Rennlist Articles: Here's How Porsche Has Changed Along the Way
Joe Kucinski
10 Most Unnecessary Porsches Ever Built (And Why We Love Them)
Verdad Gallardo
Porsche 911 GT3 S/C vs 718 Spyder RS: 10 Categories, One Winner
Joe Kucinski
This Builder Is Turning Heads With Its Slantnose 911 Creation
Verdad Gallardo
Porsche 911 GT3 Artisan Edition Pays Homage to Japanese Culture
Verdad Gallardo
Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look
Verdad Gallardo
10 Porsche Colors That Have More Personality Than Most People
Verdad Gallardo
Guntherwerks' Final Speedster Creation Is the Ultimate Porsche Restomod
Verdad Gallardo
Rennlist Member
Rennlist Site Sponsor
Joined: Jun 2001
Posts: 6,469
Likes: 13
From: Ball Ground, GA
An alternator converts rotary energy into electrical energy by moving a magnetic field (the armature or rotor) thru the coils in the housing. The magnetic field MUST be present for the alternator to generate electricity.
This magnetic field in the rotor is initially created by the excitation current that is supplied thru the charging warning light and the parallel resistor. If the excitation current is too weak (bad resistor, bad bulb, bad connection), but present, the alternator will START charging only at higher-than-normal RPM levels. If the excitation current is not present at all, the alternator will never charge.
Once the alternator starts charging, it supplies its own field current. Since there is now voltage on both sides of the light/resistor combo, the light goes off. Once the alternator starts charging, the light/resistor combo has no effect.
This magnetic field in the rotor is initially created by the excitation current that is supplied thru the charging warning light and the parallel resistor. If the excitation current is too weak (bad resistor, bad bulb, bad connection), but present, the alternator will START charging only at higher-than-normal RPM levels. If the excitation current is not present at all, the alternator will never charge.
Once the alternator starts charging, it supplies its own field current. Since there is now voltage on both sides of the light/resistor combo, the light goes off. Once the alternator starts charging, the light/resistor combo has no effect.