I realize there's a million things with these carbed cars that'll cause a bad idle, but could it be an alternator?
I figured the alt has been going bad- headlights and fan dim when it's at idle- but recently the car will idle roughly and sometimes die when I let off the gas. So, could the alternator not be giving enough electricity to keep solid spark at low rpm? Or should I go through the other usual causes for bad idle?
I don't have a whole lot of time to work on the car, so I figured I'd ask real quick and see if the alt might be the cause
Thanks!
Rough idle due to bad alternator?
- LittleRed4wd
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Rough idle due to bad alternator?
86 Silver SR5 "Silver Bullet"- 3in lift, 205/75/14s, torque cam, big brakes- Sold
86 Red SR5 "Battle Wagon"- 2.5in lift, 205/75/14s, rebuilt 3ac, chalkboard hood- Totaled
86 White DX "The Gateway Drug"- All stock-Totaled
86 Red SR5 "Battle Wagon"- 2.5in lift, 205/75/14s, rebuilt 3ac, chalkboard hood- Totaled
86 White DX "The Gateway Drug"- All stock-Totaled
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- My tercel:: 81 tercel sr5 GTS (4age RWD and 4WD application on build up for the moment) now im running a 3a with weber 32 dmsa 100,corolla gts front suspension, sway bar and steering, troush exhaust
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Re: Rough idle due to bad alternator?
I kinda doubt the alternator as something to do with that unless your battery is bad as well!
Dont let your eyes to fool you!!!
Labine R.
Labine R.
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Re: Rough idle due to bad alternator?
That is normal operation for the alternator, in fact a quick alternator check is to turn the lights on at night, start, and than rev the engine. IF the lights get brighter, than alternator is good. The car will continue to run and provide a strong spark, even if the alternator was dead, it just draws from the battery.
You likely just need to adjust your idle up, or perhaps the float level. Also check for a vacuum leak in all the hoses.
Do not exaggerate, there is only about 800 or 900 things that will cause a bad idle.
You likely just need to adjust your idle up, or perhaps the float level. Also check for a vacuum leak in all the hoses.
Do not exaggerate, there is only about 800 or 900 things that will cause a bad idle.

'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)