I have a 98spec JDM ITR motor, p73, all bone stock. It idles high at 1,500 rpm when car is moving even though my clutch is disenguaged. But when the car is "completely" stoped, it instantaous drop to the perfect idling position, like a normal car, WHY? , I have done many things to try to fix it before I am going to the dealer. I changed the clutch, thought it might be since the car idles high when moving, I changed PCV valve, checked Timing, cleaned ICA, even got a grounding kit and new battery thinking that it needs a charge. I am clueless now, lol, please help out?

 

On yes, one more thing, I just changed my PCV valve because I thought its clogged. Why did I thought it is clogged all of a sudden, because one day, I drove the car for 5 hours straight, and the oil cap decides to pop into two pieces, so I thought this can be because of my idling problem that I have been having, and built pressure in my engine. I dont' know, but I am worried, my engine is really clean, 240+ all around compression. I dont' want to mess it up.. Help please

 

Oil caps (plastic) have been known to break for race teams, which is sort of why Mugen and others offer metal ones.

The idling thing is normal, until the car stops moving (as you've said).

Good luck with everything.

 

Thats what everyone has been telling me, I don't think its normal because when ever I drive it hard or for a long time, the moving idle will become 1200 rpm, and when it is completely stoped, it will go to 600-700, which what makes it weird.

In another word, Instead of idling at 1,600 rpm when moving, and drop to 900 rpm, it does the above...

 

As long as the idle goes down to "normal" when stopped, you don't have a problem.

 

but it doesn't when the car is being driven for a long time or hard, sometimes the moving idles is 2200-2300 rpm,

 

any comment will be helpful

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zygspeed &raquo;</TD></TR><TR><TD CLASS="quote">As long as the idle goes down to "normal" when stopped, you don't have a problem.</TD></TR></TABLE>

Listen to this man . Base on what u said, your car seems fine. Why waste you money at the stealership for them to tell u that.

 

Sometimes, after hard drives, its moving idle is at 1000 rpm which is super normal, but it drops to 500 when completely stop, which is super not normal... it just dont' feel right,

 

Oh, by the way, did I mention that i have an OBD2B car but the ECU is OBD2A, so I have a harness, but some wires off the original wirings are cut, is there a purpose to the cutting, is it because I had a Apexi Power FC ECU?

So my point is that the missing wiring is causing the ECU to not work in its full potential?

 

isn't there somethign called a fast idler as well, its just idle's high for a split second until you come to a complete stop it'll drop right back down.

 

well, to be more detailed, after I let go the clutch at around 4000 rpm, the rpm will drop down in a normal speed to 900(which is normal) then jumps right back up to 1500, don't know if thats normal,

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nautica_t &raquo;</TD></TR><TR><TD CLASS="quote">isn't there somethign called a fast idler as well, its just idle's high for a split second until you come to a complete stop it'll drop right back down.
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Yep, I always wait for the drop in RPM before I shut it off. Not sure why, maybe I'm just weird like that.

 

Listen to zygspeed! He is right! There is nothing wrong with your car.

 

well, I have not yet gone to the dealership yet, but I will fix my unpined ECU wires a try. I have some wires in my original ECU wiring, thats hanging around, dont' know if thats a cause, because when I change it to a Power FC, the probelm goes away. I found a pinout diagram and goign to figure out whats missing now.

 

From my 2001 GSR ECU wiring, the A16 is hanging, but the A15 is connected. should I reverse it and have A16 connect?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HGL1668 &raquo;</TD></TR><TR><TD CLASS="quote">I have a 98spec JDM ITR motor, p73, all bone stock. </TD></TR></TABLE>

A stock JDM ITR motor doesn't have some sensors that a USDM ITR has.

Letting us (H-T) know that some wires on the harness are cut would have been heplful as well, as well as the fact that it worked fine (according to your liking) with the Apexi Power FC.

GSR and ITR wirings are not going to be exactly the same, one significant difference being the solenoid/switch for the intake runners on the GSR.

Put the Power FC (probably because some sensors were turned off in the program), back if that's what worked best. Otherwise, leave it alone.

On a personal note, I'll be trying to pass emissions in VA with an AEM EMS myself, which will be quite a trick for any number of reasons ....

 

Well, from the Original ECU GSR wiring, only one pin with a wire that is not connected to anything, and it is the A16 pin,

I also have a OBDIIB to OBDIIA conversion harness,

So what sensors are the Power FC overwriting, i want to know, anyone?

 

Crank fluctuation sensor (for sure, in with the oil pump I believe), VTEC pressure switch, one or two other little things like that.

I did a quick search but nothing good came up in the archived files, though I do remember reading about all the things people with JDM motors had to change/replace/add in order to pass CA regs.

 

So, what can I do to fix my problem, rewiring? dont use the sensor?

 

Still got the Power FC?

 

yes
However, I want to fix it without using the FC, but if I really have no choice, I will put it on

 

https://honda-tech.com/zerothread?id=1249397

https://honda-tech.com/zerothread?id=739719

Best I can do after a long day at work and ....

 

thanks, I see how the vtec solenoid is different and the IM is different than the Usdm one, but my ECU is JDM, isn't that suppose to corrispond to my JDM motor. So I am think its in the wiring department, should I take some wiring out so the ECU do not have to worry about it?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HGL1668 &raquo;</TD></TR><TR><TD CLASS="quote">thanks, I see how the vtec solenoid is different and the IM is different than the Usdm one, but my ECU is JDM, isn't that suppose to corrispond to my JDM motor. So I am think its in the wiring department, should I take some wiring out so the ECU do not have to worry about it?</TD></TR></TABLE>

anyone?