Help will be appreciated

aaron0811 · Post by **aaron0811** » July 28th, 2006, 1:05 pm

I know some might complain i'm posting this problem again... but i'm kinda new to this website... any help will be appreciated ...

My problem is that....

My car jerks and RPM goes down to around 400-500 when in D or R mode... when idle. It only happens when i switch on the A/C

If my air-con is off... no jerks whatsoever even idle or in those D or R mode... no problem....

Funny thing is.. when the engine is cool... even if i switch on the air-con, there wont be any vibration at all...

But when the engine is warmed up... the whole car will definately start vibrating unless i switch off the A/C....

What should i do...

Another problem...

In traffic jams... once i shifted to "D" ... if i stay away from the brakes.. the RPM goes back to 900... but when i hit the brakes, even gently, the vibration starts again.

My mechanic told me i had to change the mounting... but i doubt so that its the mounting, since if i switch off the A/C... the vibration stops and RPM goes back to around 900

i could be wrong though

Again... help will be so much appreciated...

Thanks in advance...

ariesdude · Post by **ariesdude** » July 28th, 2006, 1:10 pm

Sounds like the classic alternator problem - Some easy fixes would be to add a ground wire kit and upgrade to a 90 amp GS alternator.

atlantamx3 · Post by **atlantamx3** » July 28th, 2006, 1:16 pm

Search for LOW IDLE, click the box for "search all terms"

There are hundreds of replies that will give ideas of what to do or where to start.

its a common problem with the MX-3s...

xtreme velocity · Post by **xtreme velocity** » July 28th, 2006, 1:20 pm

i had the same problem..but i also found out where iw as getin gas..it was bad gas..so i didnt mess with it till i cleaned the tank n got good gas..now it runs better than ever..cheaper gas is not always the best..lol..

aaron0811 · Post by **aaron0811** » July 28th, 2006, 1:37 pm

THanks for the replies....

But to be honest... i'm a car dummie....

I just know how to drive.. lol...

So, you were mentioning about the alternator... how does it help in solving my problem ??

So, there are no problems with the mounting right ?

And... since the aircon is the one that is causing the crazy vibration... will it really help by installing the alternator you mentioned ?

atlantamx3 · Post by **atlantamx3** » July 28th, 2006, 1:47 pm

Seriously--

Hit the SEARCH button at the top of the forum and follow the directions I posted.

It will show you that this is common and several things may be causing your problem.

It will give you a place to start looking anyway.

aaron0811 · Post by **aaron0811** » July 28th, 2006, 1:49 pm

I did... but none of those mentioned about the A/C causing the vibration and low rpm...

Or maybe i missed it...

Well.. i read about the low idle, low rpm and stuff.... i mean... i'm not sure any of those guys had those problems only when the A/C on....

Thanks again.

mazdamx3sohc · Post by **mazdamx3sohc** » July 28th, 2006, 1:55 pm

i HAVE this same problem, once again our cars come with a weak alternator and you need to upgrade it to the v6 (search on the swap) and a grounding kit might help a little too. like i said.

ariesdude · Post by **ariesdude** » July 28th, 2006, 1:58 pm

Just take a length of 4-8 awg wire and connect one end to one of the alternator mounting bolts and the other end to the battery negative - you might see a bit of improvement.

mazdamx3sohc · Post by **mazdamx3sohc** » July 28th, 2006, 2:00 pm

think that would work? good idea.

aaron0811 · Post by **aaron0811** » July 28th, 2006, 2:03 pm

Ooohh OK !!

Thanks !

Will do it...

aaron0811 · Post by **aaron0811** » July 28th, 2006, 2:06 pm

By the way...

Nice Rides you guys got there...

mazdamx3sohc · Post by **mazdamx3sohc** » July 28th, 2006, 2:11 pm

why thank you.

Limegreen mx-3 · Post by **Limegreen mx-3** » July 28th, 2006, 3:07 pm

for the a/c u do know it a power robber as soon as u turn it on. car feels slow vib. at idle doesn't acc. very fast.

mazdamx3sohc · Post by **mazdamx3sohc** » July 28th, 2006, 4:39 pm

yeah, thats why you should get a v6 alternator it supplys it with more power.