Ok.. so I got a NEW yes NEW TPS and installed it... I warm the engine and use the mazda light method... I think its correct since only one light shows. But my idle won't rest back down to 750 or so RPM's without a nudge of the throttle where it hits the TPS. If I leave it then it will stay at about 2000 RPM's and won't calm down at all without my nudging it. Now I have had similar problems before I replaced the TPS and swapped out some of the throttle parts (nothing major I don't think) but usually a quick hit of the gas peddle and the idle dropped down. I was wondering if timing might have something to do with it, since I haven't messed with that.

I just went out and got the car to normal operating temp and then shut it down and plugged in mazda checker lamp and all is good, but still have the high idle issue. I am wondering if maybe the throttle body itself might be sticking a little, since even at full rest it still can move further toward the rest position, and thats how I get the idle to come down to 750 RPM from the 2k RPM it is sticking at.

Any help would be greatly appreciated.

 

im gona assume that youve checked for vaccuum leaks already

maybe even a stuck throttle if a tap of the accelerator made it drop

 

pretty sure no leaks, I have check all the hoses and can't hear a hiss or any kind of noise that indicates leaks. I did think of that and am pretty sure it is ruled out. Altho when I get the Idle down to 750 it isn't a steady 750, sometimes it is a little rough and will go between 550 and 750, but mostly steady at 750. I don't know if it would flux due to mods of the car or not. But I have K&N filter, with RB true dual exhaust, stock new O2 sensor, and thats about all that is modded for the basic aspiration of the car.

 

I would shave your head before you go crazy. :O

 

is the throttle body thermowax valve still on the throttle body?... Might be sticking or failing

 

Is on the body, and I can see that it is coming off of the thermowax, but it might not be rolling completely off so I was going to take the TB off and re-adjust it to make sure all clearences are proper. I replaced the thermowax when I replaced the motor.

 

So I just did another cold start to warm up, and I noticed that before I replaced the TPS and also the double throttle diaphragm and the TPS adjust screw arm, I was going through the normal warm up procedure. Jump to 3500 RPM's sit for a few sexonds then it would come down till the cold start procedure was done. But now it doesn't do that, it just goes to like 2500 RPM's and sits till its warm and will only settle to about 2000 RPM's. Would replacing either of those 2 have effected the normal cold start procedure?

 

auxilary ports working ok? I've had a stuck auxilary port mess up my idle. Don't ask me how that works exactly but Landers even mentions in his electronic 6 port writeup that auxilary port problems can affect idle.

 

I'd put my money on a sticky throttle body. You'll pretty much have to pull it off to verify. But I'm seeing more and more sticky TB's that people hunt as electrical related idle issues. Just make sure its closing all the way before you go any further.

Also, when checking it, check to see that it closes from 100% throttle,BUT ALSO then check to see that it closes from 1, 2, 3, 4, 5%.....I find people make the mistake of opening it all the way and letting it jam itself closed then think its fine. When in reality if they open it slightly and let off the throttle it will stick - but the enertia from going full open and letting right off allows it to get past the sticky area.

 

I had almost exactly the same problem not to long ago and it turned out to be a sticky throttle. The fact that you can "help" the idle go back down with the pedal makes me think that this is exactly your problem, as mine did the same thing. I suggest hitting the throttle body with some gunk remover and make sure that your throttle cable isn't to tight. If that doesn't work then take the throttle body off and degunk the butterflys. While your at it it wouldn't hurt to take the BAC off and degunk it as well, but I would say with 95% certainty that your throttle is sticking a little.