Engine idle trouble

[z585]

When I am at a stop sign and my engine in hot my car idles at about 500 rpms. But sometimes when I am sitting there and my cooling fan kicks on my cars rpms drops to about 100 and the car begins to act like it is going to die on me. usually I just give it alittle gas and it stops. What could be the cause of this and how do I fix it????????

If it matters my car is a auto.

Josh McCown

 

[Kooldino]

Maybe try turning up your idle?

Or it could be part of a bigger problem, something with fuel, etc. Take it in to Mazda if it's under warranty.

 

[ATLskate]

I had the same problem when i installed my Air Intake. after i got it on, i'd crank it up, and it'd drop down to about 500 RPM, and die, until the engine got warm. the problem was that i had to unplug some wire from the connector near the throttle body to screw on my clamps for the intake, and i simply forgot to plug it back in.

 

[Equinox]

from what you described, it sounds like you are running very very lean. I'd just reset my ECU

 

[z585]

ok

I tryied resetting my ECU and it still idles at 500rpm (i dont know if this is right or not) but it has gotten cold down here so my engine has not got hot enought for the fan to kick on so I dont know it that has worked or not (but I think it did). you can tell some improvement in the way it drives. But if it doesnt work could the problem be from a low battery or spark plugs? (prob a stupid ?)

Josh

 

[Equinox]

hmm all I can think is to check your oil and transmisison fluid

 

[1sty]

how do you reset the ECU?

 

[Equinox]

1) Disconnect your (+) battery terminal under the hood.
2) Let sit for 10-15min disconnected.
3) Reconnect battery
4) start car and let idle for about 5 minutes - watch how the idle jumps around some
5) turn off car when idle levels off (after the 5 min.)
6) You are pretty much done, next time you go driving your car should be recalibrated.
7) May take 2 different starts for car to level out its idle.

 

[troll]

Try checking the IAC motor (not sure if these cars or so equipped since I do not own one, I am looking around at into since I am considering one). But this is supposed to regulate idle based on air temp/density based on input from rpm, and maf/map sensors and control the idle under different conditiions. This may be malfunctioning. If this was the case it SHOULD throw a code but you never know.

Troll

 

[Equinox]

Notice the MAF directly connected to your filter - make sure this black box is directly connected and fitted right. - not loose.

I noticed on your intake system I can't find where you mounted the sensor that goes into the intake just before the air hits the MAF (MAF is the little black box that connectes directly to YOUR intake filter) I put a circle around the sensor on my engine bay, to show you what it looks like, infortunately you can only see part of the ring for where the sensor is stuck into the intake tubing - just like in the stock intake.

I may be wrong but it appears to me that your sensor is not in your intake, and if this is the case, woudl be the reason why this is happening.


(also, for those of you who notice the foam piece rigth after my MAF, it's the AEM air bypass, don't give me crap about which side it is on, I know what I am doing.)

 

[1sty]

Notice the MAF directly connected to your filter - make sure this black box is directly connected and fitted right. - not loose.

I noticed on your intake system I can't find where you mounted the sensor that goes into the intake just before the air hits the MAF (MAF is the little black box that connectes directly to YOUR intake filter) I put a circle around the sensor on my engine bay, to show you what it looks like, infortunately you can only see part of the ring for where the sensor is stuck into the intake tubing - just like in the stock intake.

I may be wrong but it appears to me that your sensor is not in your intake, and if this is the case, woudl be the reason why this is happening.


(also, for those of you who notice the foam piece rigth after my MAF, it's the AEM air bypass, don't give me crap about which side it is on, I know what I am doing.)

I believe thats the air temp sensor.

 

[PRO 5]

What does the air temp. sensor do? I know that it tells the ecu what the intake air temp is (duh!) but if it is not hooked up, what would it affect? I have a turbo now and I don't have it hooked up and I am having the same problem. It will idle fine but if I go on the boost and then come to a stop, my idle will start to get lumpy. If I rev it up a little then the lump goes away and the car idle perfect again.

Dave

 

[1sty]

i have the same idle problem as do many peolpe on the board and I have the temp sensor hooked up into my turbo kit. I believe the temp needs to be in place for the ECU to properly judge the air coming in.

 

[z585]

Well the pics of my car are alittle out dated. But let me get this straight being that my intake setup is more of a ram air. The air will prob be hotter comming in. So the air being hotter is going to be a factor of how my car idles? I made my own intake (compared to the pics there is a different size pipe, different air filter and the location where it comes out at is a little bit different) and to make sure I got everything properly aligned is there a certain distance that there has to be between my air sensor and my MAF?

Josh

 

[Equinox]

to those guys with the turbo, do any of you have an FMU or Air fuel gauge? It would tell us if you are running lean or rich - which this sounds like you guys are running lean - but then again it could be something totally diff.

 

[1sty]

I know my idle is slightly lean. Bill at FM has a hunch that my stock FPR is out of spec. I sopose this could have happened to alot of people. I retained all sensors in the turbo install and I still have these issues. The idle fuel pressure should be between 36-40 PSI mine is 35 PSI. Once I verify my guage is right I will take care of the FPR to find out what the issue is.

 

[gaZOOM-ZOOM]

Equinox Knows what he's doing? dude if you don't know what you are talking about maybe you should'nt put it on here, inaccurate information is more harmfull than none at all..... ZOOM-ZOOM. :wtf: :bs:

 

[gaZOOM-ZOOM]

1) Disconnect your (+) battery terminal under the hood.
2) Let sit for 10-15min disconnected.
3) Reconnect battery
4) start car and let idle for about 5 minutes - watch how the idle jumps around some
5) turn off car when idle levels off (after the 5 min.)
6) You are pretty much done, next time you go driving your car should be recalibrated.
7) May take 2 different starts for car to level out its idle.

Dude this is pathetic, did you learn this from delivering pizzas??????? the day that you get that ecm shoved up your rear end and told "it aint warranty" cuze you spiked the damn thing, then what you gonna do with the damn thing?

 

[Equinox]

Dude this is pathetic, did you learn this from delivering pizzas??????? the day that you get that ecm shoved up your rear end and told "it aint warranty" cuze you spiked the damn thing, then what you gonna do with the damn thing?

You can go ahead and be a hater all you want and gain the fun that goes along with it, but unless you have something specificaly wrong that I have said, I'd be best you not say anything.

 

[1sty]

Dude this is pathetic, did you learn this from delivering pizzas??????? the day that you get that ecm shoved up your rear end and told "it aint warranty" cuze you spiked the damn thing, then what you gonna do with the damn thing? [/QUOTE

Why don't you enlighten the rest of us on how its done instead of just being an asshole.