msp idle at 500-600rpm normal?

NjMpSpeed

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Spicy Orange Msp
hey guys iv had my msp for about 2 years now 22k miles and iv just recently noticed that my car is no longer idleing at 800 rpm its around 500-600 rpm...and recently when sitting in traffic or at idle the rpms will bounce down to about 350-400 rpm any ideas??? i have no engine mods

is this normal?
 
spark plugs.
have u repplaced them in the 2 years u've owned the car?

and i dont think it's a vacuum leak.
 
I get the same thing and I have replaced the plugs multiple times thinking it might be that. My guesses are EGR valve, vaccuum leak, or O2 sensor. Do you have a K&N or other oil-impregnated filter?
 
about 235,235,765,843,345 people with protege's (MSP's or EX...) have this problem. There's a lot of posts about it. basically, nobody can really figure it out. it's not the EGR valve, that's what i tried. some people have just turned up their idle about 100RPMs and say that helps a lot. otherwise, good luck to you and welcome to the problem... :(
 
If you go back to stock intake does it go away? I hear the MAF is very picky about how the air flows through it, and many intakes screw with the readings somehow. I have this problem and an aftermarket intake, I've been meaning to try going back to stock, but I've been lazy about it.
 
peepsalot said:
If you go back to stock intake does it go away? I hear the MAF is very picky about how the air flows through it, and many intakes screw with the readings somehow. I have this problem and an aftermarket intake, I've been meaning to try going back to stock, but I've been lazy about it.


i really doubt the CAI has anything to do with it, especially at idle. Clean the air filter or replace it if you think that might be it, but its probably a vacuum leak. Check all the vacuum hoses in the engine bay for cracks or breaks.
 
Stock here, too.

I think that Mazda has a plan to slowly drive thousands of people insane with these problems. Someone out there HAS to know what causes it. Is it just the people who get cold weather? Maybe the ECU is just so retarded that it freaks out with anything under 30 degrees. Who knows.
 
Mine freaks out in all weather. I think idle problems can be caused by lots of things though. A solution for one person might not be the same solution for everyone else.
 
If I ever get my hands on a wideband and a laptop, I'll be logging some data like a mofo and maybe figure something out, or maybe just tune my afc to fix it if possible.
 
In my opinion it is not normal. The factory idle rpm is 700. Your plugs should be fine with only 22K. I would take it back to the dealer and let them solve it for you. Or you can give a basic tune up and set the timing if you have the know how. My RPM would occasionally dip, although not as low as yours. I tuned it up and it has not happened since.

Each MSP is different and they all seem to have a few gremlins. Good luck solving your issue.
 
If your idle is a steady 500rpm then your check engine light would be on. In which there is a tsb for idle problems on proteges. If people are having real idle problems that are stock bring it to a dealer and show them what its doing.
 
I have once. They said its fine. But its not. It dips low at times but they cant see it so its not an issue. :(
 
I adjusted my idle screw even though everyone said oh noes you can't touch that and it idles great now. just don't set it too high or you'll get a cel
 
On the intake side of the throttle body, bottom rear corner there is a 4mm hex bolt secured with an 8mm locknut. It's kind of hard to get to, but there's enough room for a 1/4 drive ratchet. Loosen the nut and turn the bolt clockwise a little to raise the idle, like a quarter turn at a time. Remember the ecu wants to compensate for it so you might have to go back and adjust it a little in the future. remember to re-tighten the locknut so it doesn't vibrate out.
 
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