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rough idle...bad alt?


oxygen800r
04-13-2005, 08:15 PM
i'm getting pissed dammit. first the broken handle now this. all within like 2 days.

i'm leaving class and my car idle dips to 100. i drive home and let it cool off. i tried to start it and nothing.
i took the battery to vatozone and they said it was bad.
i went ahead and grabbed a redtop and swapped them out.
it started nicely (assuming it was the full charge on the new battery)
then it dove down to 500 and stayed there, keeping a rough idle.

my first inclination was a boost leak. but would that make my battery die?
or was it just a weird coincidence?

96spyderman
04-13-2005, 09:13 PM
No it would not be a boost leak... you only really feel a boost leak when there is boost!
I would have your alternator checked because if it is going bad it won't be able to provide enough juice to charge the battery and keep all electrical running.. ie your spark...you should be able to disconnect the battery while the car is running and the alt should be able to keep it running...if it doesn't then there is a problem with the alt or wiring..bad connection, corroded wires.....
Just a thought......my :2cents:

Have you done anything recently to the engine that might cause this?

oxygen800r
04-14-2005, 07:20 AM
the last thing i did to my car was the fmic about a month ago.
the rough idle made me think of a boost leak but it was more of an afterthought.

i was going to try that old school alternator "test" but i have a powered sub and my alarm hardwired and i'm not too sure that those two alone won't suck the juice out of the battery.

i'll pull the alternator and run to vatozone to get it tested.

96spyderman
04-14-2005, 04:11 PM
Just curious.. is Vatozone the hispanic version of Autozone? lol

oxygen800r
04-14-2005, 05:56 PM
autozone is vatozone because the one i go to is hood.

i had the alternator tested and it was perfect. i picked up a new set of ngk wires and i hope this is the problem.
if not, i guess i'll replace the coil.
other than that, i really have no idea.

oxygen800r
04-14-2005, 09:05 PM
not the wires.
tomorrow i'll put in new plugs. if not, i'll replace the coil.
other than that, i'm at a loss.

after i replaced the wires, i started her up. it idled normally until i put it in gear. then it dropped to ~200-400.

oxygen800r
04-15-2005, 09:56 AM
this is now only happening when i turn on the a/c.

i'm still hunting around the vfaqs and dsmtuners for any guidance.
if anyone here has any suggestions, please let me know.

EDIT:
this whole time i forgot to mention there is NO CEL.

oxygen800r
04-16-2005, 06:19 PM
so here's an update for anyone paying attention:
the throttle cable was getting "stuck" in various positions causing a weird idle.
i lubed it up and all is well again in dsm land.

but i may be in the market for a newer car soon.
in order to make room, my baby would have to go.

maybe.

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