idle prob

[nocar]

i diconnected the negative from teh battery so that the ecu could reset because i wasnt sure if the person before me was putting regular in instead of premium so i left it disconected for like 10 mionutes then conected it and drove around
when i get to a stop the rpm goes down and then it drops and the car shakes then it goes back up to normal then goes down :wtf:

 

[fakieair]

Ive had that happen to me twice once in the cold though so I blew that off, the other just last week, but I went the gas station bought gas and with alot of scratching my head it just seemed to go away.

 

[alexlitov]

disconnect the neg again and let the car idle for a few minutes.

 

[fakieair]

So ill bump this just to make sure its not a big deal, because I dont have a clue.(scratch)

 

[fakieair]

does that mean its electrical???

 

[1sty]

I was chasing that problem for 6 months and heres what I found.
Many Proteges of all makes have had there deal of issues like your. Many people don't get it until they replace the intake with a K&N filter for me it wasn't until I got a turbo.
Either way sometime the computer can fix itself witha reset in which it relearns the car. However often not.
However I found the FIX.
I am guessing that many throatle bodies are coming froom the factory poorly adjusted or maybe there is some bS going on for emmissions reason. Why ever it is doing it I don't know.
I solved my prolbme by resetting the stop point on the intake buterfly. I basicly keep it open more. If you look at the TB on the right side by the fire wall there is a allen head scre that had a 8 mm lock nut on it. That sets the TB butterfly. I opened mine just a bit and now i never have an issue where as before my car would hit 0 RPM when coming to a stop.

The idle screw won't do dick as the ECU will override it.

There are a handful of others out therre that have found other solutions like getting a new battery or somehting along those lines but Since I already had another battery and a huge alternator not to mention all 1/0 power and ground cables replacing the factory i knwo my car was electricaly fine.

 

[fakieair]

Ill keep that in mind when I finally do something to my p3. but now that I think about it, the dead zero hit I had was probably my fault.- It was cold, I was low(not out) on gas and parked on an incline, plus I only drive her mabey twice a week and if Im lucky once a week in winter. Hell for all I know shes just bitchin' cause I dont take her out enough--- and I thought cars were better than women.

 

[MrMp3]

I dunno never had that proble
KNOCK ON WOOD

 

[DooMer_MP3]

Try disconnecting the negative battery cable again and then step on the brake pedal for a few seconds. This should discharge any remaining power. Then let it sit for 10 minutes or so and try again.

Chris

 

[1sty]

Reseting the computer can't do anything if there is a physical problem in the system.

Many member have found this does nothing to help there problems. Also keep in mind the computer is a learning one so it should adapt to a change over time as well as after a reset.

 

[FuNwaGoN]

Well I can chime in on this one. I had this problem since day one of having my car. I am still in the process of writing up a whole review on the subject. I guess I need to kick myself in the arse and finish it. Sorry MP3 NH I know you may have been looking for it. Any change in your situation?

Well it took 8 visits to the dealer and 1 of those was for a special Mazda Tech, in the first 3 months of owning my car. Well after they replaced the IAC valve, Completely reprogrammed my ECU, Reset base idle 7 times. guess what ended up fixing the problem a damn $5 rubber stopper. They said that my problem was because 90% of my driving is in stop and go traffic. because of this my foot is almost always on the clutch. Well our sensitive computers were reading that as the clutch being depressed all of the time and were trying to adjust the idle in accordance to what it was sensing. I have put approx 1500 miles on my car since this repair and have not had the idle problem even once. I even installed a injen intake and no idle problems at all. This is a Mazda tech Hotline Fix and any dealer should be able to look it up and fix it for you. As to the exact location of where they placed the rubber stopper I am not sure. I have asked the dealer and left a message with the mazda tech but have had no luck. Hey as long as it fixed it then I am fine.

On a side not MP3NH have you thought about doing the switch of a MP3 ecu to a P5. Some guys just did this at this past weekends meet here in charlotte. The MP3 is turbo and the P5 is not. Depending on the results they post I think you would have alot of people willing to do a swap.

Hopefully will have a whole summary of all of my car problems sometime in the next few weeks. My home computer has been giving me problems and thats the only time I have to work on it.

BTW just reread my post and wanted to clarify a little more what the rubber piece does. It causes a switch to only be activated when the clutch peddle is fully depressed. How it interacts with the switch I am unsure as well. But so far so good.

 

[1sty]

I actualy finanly fixed my idle issue. i just opened up the stop point on the TB butteryfly, read my first post in this tread for the details.

I am thinking of swapping the ECU out with a P5 in my car but I was hoping Terry or FM have something significant shorly to better tune any protege.

I PMed you the rest of the response.

 

[KnowMeDontYou]

Alright folks I'm somewhat new to the whole car modifying thing and i just got my P5 a few weeks ago, replaced that intake with a K&N and just like the other guy said my engine light comes on and my car is stalling (this is an automatic we're talkin about here and it is stallin). Anyways that fix with the Intake Butterfly sound about right but what is the TB butterfly, where is it exactly and how much did you turn it to open it up?

 

[TXMazdaSpeeder]

strange


when i got my mp3 it had a k&n filter, worked fine, put the aem sri on it, works fine (knock on wood) guess some cars are just pissy.

 

[Vetinari]

I know this is an old thread, but I thought I would mention that I had a probe with a similar behavior. The ecu had to "relearn" your idle every time the battery was disconnected. I just changed the battery in my MP3 and now it is doing it, thing is, it should work itself out after a while of driving, but it doesn't seem to be. Its possible it needs to be disconnected and then allowed to idle before any driving. My idle was never rough before the battery change.

Also, the IAC can become dirty and start to stick, so if you are told to replace it, it may be worth while to just take it apart and clean it first, especially if there is not a check engine light associated with it.