2001 Protege idle problem at stoplight

[slavrenz]

Hey guys,
I seem to be having an idle issue with my 2001 Mazda Protege LX 2.0. My car runs fine most of the time, but when I come to a stop (and sometimes when I start the car when the engine is still warm), my idle will dip down to about 500 RPM like it's going to stall and flutter between 500 and 750 for about 15 seconds, before it finally settles at about 750.

I have cleaned my EGR and Idle Air Control valves to no avail. I have also tried spraying carb cleaner to detect a vaccuum leak with no success. Does anyone have any suggestions?

 

[niky]

Plugs? I have a similar issue, Had to go over every single hose and check its integrity... note that as the engine bay gets hotter, cracks or leaks can get worse... I finally found my problem by reaching my haind inside the scalidng hot engine bay (around the intake manifold) and probing till I found a loose vacuum line.

 

[slavrenz]

Thanks for the reply. I just replaced the plugs and wires about 5,000 miles ago, but I am getting more and more convinced that there is some sort of vacuum leak. Problem is that I've checked all the obvious places and I can't seem to find it.

I've read a lot about using smoke to check for vacuum leaks. Does anyone know if there is a place that you can rent a pressurized smoke machine for this? Or is there a way to make one yourself?

 

[slavrenz]

bump

 

[bgibb68]

edit....are you getting any codes??

 

[slavrenz]

Nope, no codes. The weird thing is that the problem went away for a few weeks, but now it's back. Only this time the idle doesn't dip when I come to a stop, but rather when I first start the car. I know a little bit of dip is normal, but not 200-300 RPM.

I'd still like to have the piece of mind that there's no funky vacuum leaks anywhere. Does anyone know if I have to take the car to a mechanic to get it smoke tested, or is this something I can somehow do myself?

 

[bgibb68]

yeah that is weird, lemme get this straight.

no codes
egr valve is clean
intake is intact and clean
air filter clean
no noticable vac leaks/torn hoses

 

[slavrenz]

Correctamundo. My only other guess is some sort of gasket leak that somehow opens up intermittently, or some hose breakage that I'm not seeing.

I took it to a mechanic before, and he said that he couldn't find anything wrong with (it stopped acting up when I took it in). He said it couldn't be a vacuum leak or it would be doing it constantly, so he didn't smoke test it. I felt kinda bad trying to call him on that, as I'm sure there are times when a vacuum leak can occur intermittently, so I didn't say anything.

I can't believe that there's no way to rent some kind of smoke machine or do something yourself that is more comprehensive than just spraying carb cleaner. Maybe I'll open up a new business catering to this market and make a killing. (2thumbs)

 

[bgibb68]

yeah if the leak is behind a solenoid....have you cleaned replace the PCV valve??

 

[bgibb68]

have you tried cleaning the fuel and intake systems...get seafoam, everyone on here seems to like it....there is a thread around about how to use it

 

[Hookedupmp5]

possible code if you had one would be similar to a PO404.

 

[slavrenz]

Yeah, I have replaced the PCV valve, and I seafoam the engine every 5,000 miles when I change the oil. I'm not throwing any codes, so I guess I will have to take it in and just have it smoke tested for vaccuum leaks. At this point, it is still doing the idle drop sporadicallym but when I come to a stop and when I start the car, so hopefully one of these days it will throw a code. I have a sneaking suspicion that something is funky with my MAF, but I'm not getting a code for it and I don't wanna go drop $175 when I'm not sure that's what it is.

 

[protege321]

my protege does the same thing. good luck finding the issue and if u dont mind let me know what the problem was if you find it. thanks.

 

[Hookedupmp5]

I had the same problem, it went away when i removed all cats for my exhaust. I recently had to put them back on for emissions testing which, of course, is now back. The studdering or as if about to stall.

 

[slavrenz]

Interesting. I hadn't really considered the possibility of an exhaust blockage, but that makes sense that it would affect my drivability. Does anyone know if there is a way to check for exhaust blockages without having to tear apart the exhaust?

 

[R-X-R]

Try Spraying Water On The Wires And C If It Jumps

 

[Zebee88]

anyone...

Hi I am not sure anyone is still looking at this post, but I am having the same problem, my car acts like its going to stall at a stoplight, or even slowing down. It also seems to lose power while drive once in a while. I have new plugs, air filter, air hose, battery etc. Has anyone found anything wrong with this car?

 

[eszoom]

i had this problem on our camry. i used seafoam deep creep on the iac valve. and after that it idled normal. don't know if the camry and protege are similar never had a problem on my proto.

 

[Canadian-ES-GT]

I had a similar problem (P0300, mutiple missfire) and it was my EGR that was stuck open. Could it be that your EGR is clean but is just malfunctioning!!