OoBALLERoO

hey guys i need help this has been baffling me for a while. when i have the car turned on and i am idle at a red light, the rpm needle moves up and down like its dancing.. i would say it goes from maybe 900rpm to 650rpm back and forth. there's no problem with acceleration or when im driving, only when im stopped. it is definitely more noticable in the morning on cold starts. DOES ANYONE HAVE ANY IDEA WHAT THIS COULD BE??

an uncle of mine told me i have an electrical short somewhere..i dont know how true this may be or if i should even consider this as being the culprit. it does seem to make a little bit of sense however because i do have an aftermarket subwoofer hooked up with a power switch under my steering column and while im at a red light with the music on, the rpm needle does move a little more. if i turn the power switch off and turn the subwoofers off, it doesnt dance around as much.

THANKS FOR ANY INPUT! IT IS GREATLY APPRECIATED..

rbf351

if it's when you first turn the car on it's because it's warming itself up

also a short does not cause the engine to rev. what you are noticing is the alternator giving out more power than it norally would when you turn on the amp

PeterUbers

iTrader: (1)

when the tach needle jumps around b/w 600 and 900 rpms -- do you feel a shudder/vibration from the engine or is it strictly the tach jumping around?

OoBALLERoO

There is definitely vibration.. And a lot of it as the rpm goes lower.. My check engine light is on also and it's been like this for months.. I got into a car accident a year ago and it's been like this since I got the car back. I can't take the car back to acura because the car is leased and not covered under warranty anymore due to the accident.. So I'm trying to fix this problem now before the lease is up in a few months. There is DEFINITE vibration though

OoBALLERoO

anybody?

rbf351

you just answered your own question, you have a CEL with is usually an electrical issue. get that checked first, and go from there.

davenlei

I had a car that did this at idle once (not Acura) and it turned out to be a small vacuum leak. One of the small tubes that feeds off the intake vacuum had a nick in it and it caused the unsteady idle. Once I fixed the leak all was well. It was a b*tch to find though.

TLTrance

I guess I'm puzzled that your first post didn't mention that you got into an accident AND that the check engine light is on... That would've really helped...

OoBALLERoO

Okay.. Sorry for not stating that in the first post? But it's out in the open now.. Anybody else with suggestions/opinions? I just turned 20 yesterday and I'm venturing into the world of being a man on my own and I'm trying to fix this problem or get it fixed on my own without "daddy's help" so anybody's input is really appreciated.. BTW davenlei thanks for the reply I will def keep it in mind

Desert_TL

Err... yeah...

Take it to autozone or somewhere similar and have the check engine light diagnosed. They will usually do that for free. I'd bet there's at least a 90% chance that whatever the check engine light is indicating is what is wrong with the car and giving you a rough idle. So for example, if it indicates a specific vacuum leak somewhere, just replace that faulty hose for a few bucks and you should be good to go. In the future, don't drive for months with the check engine light on. In general the check engine light means just that. You should check your engine as soon as possible; there is something wrong with it.

rbf351

you are 100% wrong with that statement. a check engine light does not mean there is an engine problem, it means there is an issue with the car, and it almost always an electrical issue.

OoBALLERoO

okay well i went to autozone to see what the check engine light was on for and they found 2 problems.

1. The PCM has determined that during testing, the fuel system for bank 2 was too rich. (bank 1 identifies the location of cylinder #1, while bank 2 identifies the cylinders on the opposite bank)

2. The PCM has determined that the input from the coolant temperature sensor indicates a temperature value that is below the thermostat regulating temperature.

For problem 1, the guy who worked at autozone said that i probably have a bad oxygen sensor, but he wasn't positive. For problem number 2, he said i probably have a bad temperature sensor. I do know however, that when it's cold out and i'm driving at highway speeds, the temperature shown on the gauges goes all the way down to C, and it also takes quite a long time to heat up on cold mornings. I'm not sure if these two problems are what's causing my rpm to go up and down. What do you guys think?

OoBALLERoO

?

Desert_TL

Take it easy there. You think I don't know that? That statement wasn't meant to be taken literally or be 100% technically acurate. The point I was trying to make with that statement is that it's a bad idea to drive around for months with the check engine light on. As in, the light isn't meant to be a "suggestion"; it's meant to be taken seriously and addressed right away.

Desert_TL

1 could be an oxygen sensor or perhaps a bad fuel injector(s). Could also be a clogged air filter. I had a Saturn once that had a rough, "bouncy" idle. It was fixed by replacing the air filter. I think for number 2 it's more likely to be a bad thermostat. He probably suggested a new temperature sensor first because that is a lot easier to replace than the thermostat, which will require you to drain the coolant system.

jag123

pretty sure it will be your O2 Sensor

csmeance

go to a diffrent acura dealer, they won't know really it was in an accident unless one of the techs is smart enough to notice, my TL was totaled and only 1 of the dearships know if it in Florida