subsonicman
Member
- :
- 2002 Mazda Portege 5
my car idles real low, and puts a lean code out at idle, can i adjust the idle on my p5?
idle adjustment
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MazdaSpeeder
Member
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- Protege5 (5-spd)
If you have a low idle and a code, adjusting the idle probably isn't going to help. It sounds like another issue is causing the low idle, not that the idle is low and just needs to be raised. If I am not mistaken, the idle is controlled by the computer and shouldn't change too much. I would check EGR, O2 sensors, plugs to start.
subsonicman
Member
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- 2002 Mazda Portege 5
let me just say, head is ported, cams are cork sport, VTS is removed, plugs are new, and comprssion is raised. code is random misfire only at Idle. The Exhaust cam is causing the rough idle. the car idles at 700ish, but the durration on the cam I think is causing the misfire
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- Protege5 2003
And wires. I had one go bad and it was causing occasional stumbles. I suppose it could be a coil pack too, but that would tend to affect two plugs at a time. Even so, easy to test, just swap them and see if the problem moves.
subsonicman
Member
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- 2002 Mazda Portege 5
i just rebuilt the motor, plugs wires, everything is new. Running NGK's, with Nology wires. I really just need to adjust my Idle to around 900
subsonicman
Member
- :
- 2002 Mazda Portege 5
I really appreciate all the help
Guys, this has nothing to do with bad plugs/wires.
There is an idle adjustment screw (IAS) on the side of the throttle body. This can be backed out to raise idle but only to a certain extent. There is a throttle adjustment screw as well but DO NOT adjust that one. If you have access to the factory service manual it explains it in there. I'm actually really surprised that you're getting misfire codes with just the CS cams. As for the lean code - that should not be there, head work or not. It does seem like somethin else is off though. The stock computer should be able to keep up with the CS cams and some headwork.
Also, have you considered the possibility you really are misfiring? What compression pistons did you go with? Hopefully you're running higher than 87 octane gas...
There is an idle adjustment screw (IAS) on the side of the throttle body. This can be backed out to raise idle but only to a certain extent. There is a throttle adjustment screw as well but DO NOT adjust that one. If you have access to the factory service manual it explains it in there. I'm actually really surprised that you're getting misfire codes with just the CS cams. As for the lean code - that should not be there, head work or not. It does seem like somethin else is off though. The stock computer should be able to keep up with the CS cams and some headwork.
Also, have you considered the possibility you really are misfiring? What compression pistons did you go with? Hopefully you're running higher than 87 octane gas...
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subsonicman
Member
- :
- 2002 Mazda Portege 5
running good gas, no octane boost, only other thing I can think of is a stuck or clogged injector. Car runns awesome when you are into the peddle, it puts out a code when you are deep into it, and let off the gas...... No vacuum leaks I can tell, except for a slight leak in the manifold, where a bolt broke, Still looking for a new bottom half of the intake, or I might just get the protege garage manifold. Forgive me for being stupid, or sounding stupid, was I right in removing both sets of butterflies from my manifold? I Ask, because the corksport one still has a set of butterflies, and my car idles for crap and I am grasping at straws
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- -- 03 P5 / 23 CX-5 --
I'm leaning towards injector or weak fuel pump issues. Seafoam it or run injector cleaner of some sort thru it & or check the fuel pressure. Could even be dirty sock filter on the intake of fuel pump in tank. Lean = too much air, not enuff gas. Have you checked for vacuum leaks?
Since when is a misfire not related to bad plugs/wires?
When you have cams that are more aggressive than stock and a decently worked head. The idle gets a little too lopey and the knock sensor doesn't like it. Feel free to read up on those who have installed "twiggy cams" and you'll see what I mean.
I'm not saying that this can't happen (and yes, I have read the posts by those who have installed Twiggy cams). My point is that I don't think you should rule out the plugs/wires completely.
He said both the plugs and wires were brand new. While there is a slight possibility either are bad, I don't think he should immediately write off the possibility of there being something bigger at work here - especially considering the amount of aftermarket work done. If this was a stock or lightly modified P5 then it would be a different story.
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- -- 03 P5 / 23 CX-5 --
Since the OP question was about a lean code?
subsonicman
Member
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- 2002 Mazda Portege 5
Took out the NGK Ir plugs, and installed a new set of NGK Platinum plugs today, no change, I also changed my intake manifold gasket, and thortlebody gasket today, and replaced the EGR Valve, the Idle has at least become drive able, but it is still live able.
Try just regular old NGK plugs. Our cars are notorious for not liking anything other than standard NGKs. Seems like you might be onto a solution though. Good to know the CS cams and some headwork won't necessarily throw the car into fits. That gives me some hope down the road.
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