04 Mazda 3 GS Rough Idle at stops

[tooviral]

Recently my 04 Mazda 3 would drop to 3rd gear while driving and the AT light would come on, and would not change gears until I came to a stop and it the reset itself. Found out it was a sensor(Pulse Generator) on the tranny . Replaced that and fixed that problem.

Now that I did that, the car, now when coming to a stop the idle goes from 500 to 1000 like a yoyo and 8 out of ten times will stall. Only does this when in drive, not in park or neutral.

Anyone have any deas on whats up. Some have said to clean out the throttle body and others have said its a bad PCV valve.

Gonna clean the throttle body when I get a chance, just so damn cold outside.

Nelio

[tooviral]

btw, how do you edit a post?

[S.F.W.]

btw, how do you edit a post?

you get 100 posts.

[sas]

Disconnect the battery for ten minutes to be insured it’s not a problem of PCM learning.
Do check maf and throttle body connectors and wires, maybe you touched them.
It doesn’t like on the PCV, purge valve, or throttle body. Most possible that you have changed the input turbine sensor or VSS and this sensor still has a low sensitivity at low vehicle speed. What I can say … Dealer. Only he can check it.

[tooviral]

I actually had a diagram of the tranny and did replace the right one, hence the problem has gone away. Gonna clean out the throttle body either tommorrow or wed. Will dissconnect battery also, while I'm cleaning it. Might as well do they MAF also. Anyone know if you can use the throttle body cleaner on the MAF???

Will post with my results when I'm done.

[McGuyver_3]

yes you can use TB cleaner on the MAF sensor. I suggest you remove the TB off of the car to clean it. Will prevent the cleaner from getting in to the intake

[dcox]

My 2005 GS with 80,000 was stalling when idling low ( at red lights, in traffic ) If I put it in neutral and brought the rpms up it would not stall. Stalling was intermittent. I bought the purge valve from autopartswarehouse.com for 70.95. Installed it in 15 minutes. Car works fine now! The dealer wanted one hour of labour and 120 for the part.

[tooviral]

yes you can use TB cleaner on the MAF sensor. I suggest you remove the TB off of the car to clean it. Will prevent the cleaner from getting in to the intake

Yup, was planning on removing it as I want to get to the intake side as well


My 2005 GS with 80,000 was stalling when idling low ( at red lights, in traffic ) If I put it in neutral and brought the rpms up it would not stall. Stalling was intermittent. I bought the purge valve from autopartswarehouse.com for 70.95. Installed it in 15 minutes. Car works fine now! The dealer wanted one hour of labour and 120 for the part.

Thanks for the info, if cleaning the TB and MAF dosen't work, thats sure to be my next step. TB probably needs to be cleaned anyways.

[TheMAN]

an updated ECU flash fixed rough idle problems (the 04's original flash is pretty buggy... mazda kept releasing updates till last year IIRC)... the other common issue is dirty throttle bodies... if both of these don't fix it, then it's usually a bad purge valve

[tooviral]

Does anyone know how much an ECU flash costs?

[McGuyver_3]

Does anyone know how much an ECU flash costs?

more then likely 1 hour in labour

[gskills]

Do the cheap thing first and clean that throttle body out.... mine was dirty as shit
Take it out and use a soft cloth and some cleaner....


This Fixed all my idle probmes like what your having then start to try the other things if no luck...

look at my old posts there is a picture of what mine looked like somewhere

[tooviral]

Finally got a chance to get to the throttlebody. It was caked on the engine side

http://i51.tinypic.com/15noha1.jpg

Airfilter side also looked cleaner but you can see the edges of the top and bottom of the butterfly were dirty, hence causing my erratic idle

http://i56.tinypic.com/2r7yg6a.jpg

Nice and clean after I used a throttle body cleaner, took like 20 mins to clean this sucker.

http://i53.tinypic.com/2w3xb4h.jpg

Car now runs well, idle seems to be very good and no erractic idle anymore. Lets hope the fuel mileage improves also. I had also clean the MAF also cause I had the hood open.

Nelio

[McGuyver_3]

That seal does not look in all the greatest shape. But then again could also be the picture itself

[TheMAN]

more then likely 1 hour in labour

warranty pays 3/10 hour, but since it'll be customer pay work, it'll probably be 1/2 hour or more