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Re: when putting car in gear, idle goes up in rpm??
Posted: November 11th, 2010, 3:33 pm
by mikeinaus
MrMazda92 wrote:I'll try again.
When the clutch is IN, without ever being released in the process I am describing; The RPMs change when the car is put in gear.
A good example would be stopped at a red light:
You see lights perpendicular to yours go yellow.
You push in the clutch, and put the car in first.
The RPMs go up.
+2 my car does the same thing. clutch pressed in neutral = 650rpm idle, move shifter into gear with clutch still pressed = 850rpm or so idle
Re: when putting car in gear, idle goes up in rpm??
Posted: November 11th, 2010, 3:35 pm
by wytbishop
Check again and tell me....does the RPM change when you depress the clutch...or not until you put it in gear?
If nothing happens until you select a gear that is a total mystery to me. There is no sensor or mechanical device of any kind that senses the position of the gear shift lever or the shift shaft inside the tranny.
Re: when putting car in gear, idle goes up in rpm??
Posted: November 11th, 2010, 3:37 pm
by wytbishop
mikeinaus wrote:MrMazda92 wrote:I'll try again.
When the clutch is IN, without ever being released in the process I am describing; The RPMs change when the car is put in gear.
A good example would be stopped at a red light:
You see lights perpendicular to yours go yellow.
You push in the clutch, and put the car in first.
The RPMs go up.
+2 my car does the same thing. clutch pressed in neutral = 650rpm idle, move shifter into gear with clutch still pressed = 850rpm or so idle
Well that is a stumper. There is nothing in the engine control system that tells the ECU that the MTX is in gear.
Re: when putting car in gear, idle goes up in rpm??
Posted: November 11th, 2010, 4:10 pm
by mikeinaus
i thought it was weird when i first bought the car but almost 2 years and a different motor ive came to believe its normal?
Re: when putting car in gear, idle goes up in rpm??
Posted: November 11th, 2010, 8:19 pm
by MrMazda92
wytbishop wrote:The little allen screw is the throttle stop. It's just there to prevent the butterfly from slamming closed against the throttle body. back it off, close the throttle and then screw the stop in until it contacts the throttle linkage and moves it just slightly. The butterfly should still be fully closed, but resting on the stop not the housing of the TB.
Then adjust your throttle cable so that it is slightly loose. You should be able to deflect the exposed part of the cable about 1/2-3/4" without affecting the idle. Any tighter than that and it will prevent the throttle from closing fully.
Do that first...then adjust the TPS using feeler gauges and a multi meter, then adjust the idle.
wyt, I did these in this order and had an issue.
After I was done, a CEL tripped. I haven't had one on this car before, but the code was 12(TPS). I re-did the process per Daninski's instructions in one of his posts, and the CEL still goes off. Is there a special process to clear the codes on here, or does fixing the issue clear the code? Thanks.
Re: when putting car in gear, idle goes up in rpm??
Posted: November 11th, 2010, 8:22 pm
by mikeinaus
you have to reset the ecu. fixing the issue with get rid of the light but the code will be in the memory when you test it...
unplug the battery and press the brake for 30 sec then you should be good.
Re: when putting car in gear, idle goes up in rpm??
Posted: November 11th, 2010, 8:44 pm
by MrMazda92
mikeinaus wrote:you have to reset the ecu. fixing the issue with get rid of the light but the code will be in the memory when you test it...
unplug the battery and press the brake for 30 sec then you should be good.
Ah, thanks! Time to reset my stereo and clock again
Re: when putting car in gear, idle goes up in rpm??
Posted: November 12th, 2010, 12:16 am
by Ryan
I didn't read this whole thread, but there is no speculation on what sensors affect the ECM and which don't.
http://www.mx-3.com/manuals/showimg.php ... F2-014.gif" onclick="window.open(this.href);return false;
http://www.mx-3.com/manuals/showimg.php ... F2-018.gif" onclick="window.open(this.href);return false;
Re: when putting car in gear, idle goes up in rpm??
Posted: November 12th, 2010, 12:28 am
by _-Night-Shade-_
This is only a 92 thing, when I had my 92 GS it did the same thing. For the record, it has nothing to do with the clutch, only after you clutch in and SHIFT into gear without clutching out, the idle goes up a bit. I always thought it was an ECU thing for making it harder to stall the engine or something. But yeah my 94 doesn't do this. This does make sense as the 92 ECUs are different from the rest.
And there IS a way for the ECU to know when you're in gear via the neutral switch. Neutral = normal idle. Not in neutral = higher idle.
Re: when putting car in gear, idle goes up in rpm??
Posted: November 12th, 2010, 12:45 am
by mikeinaus
i have a 92...
Re: when putting car in gear, idle goes up in rpm??
Posted: November 12th, 2010, 12:51 am
by _-Night-Shade-_
Yes as does MM92, and as I used to. Told ya, it makes sense.
Re: when putting car in gear, idle goes up in rpm??
Posted: November 12th, 2010, 12:54 am
by wytbishop
Well that's clear as day. "Neutral/Clutch switch - detects in gear condition; sends signal to ECM"
http://www.mx-3.com/manuals/showimg.php ... F2-012.gif" onclick="window.open(this.href);return false;
Learned something new today. I still however don't think it's normal for the idle to change when you put it in gear. Mine doesn't. None of my MX-3's have behaved that way. Makes me think that something is out of adjustment or something on your car.
I'm out. I have no idea if it's a problem with yours couse it does or mine couse it doesn't. I am totally stumped on this one.
Re: when putting car in gear, idle goes up in rpm??
Posted: November 12th, 2010, 12:56 am
by wytbishop
That link I posted is from the 95' manual. So maybe the result is different due to some tuning thing on 92's but the capability is there on all of them I assume.
Re: when putting car in gear, idle goes up in rpm??
Posted: November 12th, 2010, 2:33 am
by MrMazda92
Well at least we know we aren't crazy!! I was starting to doubt myself there for a minute...
Re: when putting car in gear, idle goes up in rpm??
Posted: November 12th, 2010, 11:59 am
by _-Night-Shade-_
Nah don't worry. If you don't like the idle changing you could always switch to a 93 ECU but I don't think it's a big issue.
Glad I could help
