tach issue?
#1
tach issue?
I've got a 1983 GS.
When I go start it - for the first minute or two - the tach works just fine, but only up to 4500rpm. above that it just "sticks" at 4500.
I'm concerned that once colder weather hits it won't work at all - and this is my winter car, so, uhh, it kinda has to?
anyone here have this happen to them and know how to fix it?
When I go start it - for the first minute or two - the tach works just fine, but only up to 4500rpm. above that it just "sticks" at 4500.
I'm concerned that once colder weather hits it won't work at all - and this is my winter car, so, uhh, it kinda has to?
anyone here have this happen to them and know how to fix it?
#3
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Yeah. I've never had the tach 'stick' in one position. Once you get under 4500 RPM, does the tach unstick itself, or does it stay there until you shut off the ignition? Also make sure that the connection on the back of the instrument cluster is attached tightly. On my car that attachment is problematic and loosens quite easily, causing erratic tach function.
#5
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My guess is the trailing ignitor does not like the cold weather (slight open but when warmed up expands the metal to close the open circuit). You could try swapping the leading and trailing ignitor to see if this helps the tac, however it amy not run real well until it is warmed up. This will help isolate the problem though.
#7
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it shouldnt be an electrical problem.. mine does this too (infact, in winter it reads zero, then starts swooshing slowly)
if the trailing circut was faulty the tach would read zero or the current RPM, or some jitter.. i have a feeling the twin pole drive gets sticky in the cold... its no issue (i know my trailings work, even if they dont do much)
now if yours isnt weather related one of the drive poles may have burnt of is slightly faulty.. i would look into the tach unit and not the trailing ignitors.
if the trailing circut was faulty the tach would read zero or the current RPM, or some jitter.. i have a feeling the twin pole drive gets sticky in the cold... its no issue (i know my trailings work, even if they dont do much)
now if yours isnt weather related one of the drive poles may have burnt of is slightly faulty.. i would look into the tach unit and not the trailing ignitors.
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#10
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it's not the coil, my car has the same prob, like it I start the car the tach will go to about 1500 (Gsl-se), but if i cut the car off the tach just stays at 1500... I was wondering how to fix it too...
#11
I drove my old GSL-SE all winter long - never ever had trouble with it either! only got stuck once or twice, and we got a lot of snow that year.
While this car obviously won't be as nice in snow as my current beater (1991 awd talon - nothing beats awd in snow) - it shouldn't be that bad - and it will be a whole lot more fun![Smilie](https://www.rx7club.com/images/smilies/smile.gif)
well - I cleaned the terminals but the car is currently in my garage 3 feet up in the air (welding in new floors) so I haven't gotten the chance to see if anything improved or not.
I also redid the main battery grounds and both battery terminals with heavier, not-broken and 23 years old wire- not sure if it was related to the problem or not - but the old, crappy stock terminals looked like poo, and the wires even worse!
While this car obviously won't be as nice in snow as my current beater (1991 awd talon - nothing beats awd in snow) - it shouldn't be that bad - and it will be a whole lot more fun
![Smilie](https://www.rx7club.com/images/smilies/smile.gif)
well - I cleaned the terminals but the car is currently in my garage 3 feet up in the air (welding in new floors) so I haven't gotten the chance to see if anything improved or not.
I also redid the main battery grounds and both battery terminals with heavier, not-broken and 23 years old wire- not sure if it was related to the problem or not - but the old, crappy stock terminals looked like poo, and the wires even worse!
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