Ok so here goes:
95 Jdm H22 in 96 Hatch

When driving the car at any speed, if i put the clutch in the engine will drop to 1500rpms and hold constant untill i reach a complete stop. My idle is set to 1000 rpms right now and once i come to a full stop the car drops down to its normal idle. here is where it gets really weird. say i am at a stoplight on a downward slope. if i keep the car out of gear in neutral and let the car roll down the hill, as soon as i hit say like 5mph the car jumps right back up to 1500 rpms. on top of that, if i leave the car in gear and let off the gas, once i hit 1500 rpms the car will continue to keep a constant speed and not slow down. I thought it was the throttle cable being too tight but i already checked and double checked that. what else could it be? while it doesnt really hurt anything or negatively affect me, its pisses me off help!

 

my car does the same exact thing. Dont know either I gave up!

 

well i ruled out the ecu.

bump, someone help me figure this out

 

Have you checked the vss? I have a mechanical vss so I can't tell you how to check it.

 

Mine does that as well, but it did that when it was stock. And not to that extent.

Check the things that are related to idles (IAC, Idle Adj Screw, ETC)

 

idle adjust screw works fine, so thats rulled out.

i checked and cleaned my iacv so i have to assume thaqts ok.

next thing to check is voltages on the tps sensor

anyone else?

 

1 more bump, then i will just give up on it

 

The ECU has a separate rolling idle (higher idle when the car is moving) which on your car seems to be higher than normal. Since you said your idle is set at 1000, I am assuming you do not have the stock ECU.

The rolling idle on my '99 GS-R is about 950 and when I come to a stop, it then drops to 750. This is with the stock untouched ECU.

Disconnect the VSS and see what happens.


Modified by kelly at 12:12 AM 9/10/2004


Modified by kelly at 12:23 AM 9/10/2004

 

my idle is set to 1000 rpms because i didnt want to deal with vibrations in the car from my solid mounts. i adjusted it using the idle adjust screw. the ecu im currently running is a bone stock jdm p13 that i just swapped with a buddy of mine.

i assume you are telling me to disconnect the vss to see if its causing the problem?

ill try that out later, and let you know what i came up with

Pete

 

so i finally had a chance to disconnect the vss sensor to see if anything gets better. after disconnecting the vss, the car ran PERFECT. rolling in neutral produced near idle numbers exactly like it should have. so im going to pick up a new vss.

bump for other people who had this problem and didnt come up with a solution

thanks kelly for the tip, you mad my night!

 

and you think a new vss is going to fix the problem??

kelly has just told you that the ecu has a separate rolling idle, the reason this idle is higher than normal is cause you have adjusted the idle screw.

 

I got the same thing too... never new what it was. However if Im understanding this correctly it seems that kelly wanted you to unplug it to see if it was the rolling idle thing. since the ecu would think you werent moving it would just use the normal idle. I might be wrong, but you may want to hold off on the new vss.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by black2001ITR &raquo;</TD></TR><TR><TD CLASS="quote">and you think a new vss is going to fix the problem??

kelly has just told you that the ecu has a separate rolling idle, the reason this idle is higher than normal is cause you have adjusted the idle screw.</TD></TR></TABLE>

if he adjust the idle screw that far shouldn t the pcm try to full close off the iac valve to lower the idle causeing it to idle up and down?

maybe he has a vaccum leak on the egr valve or egr vaccum solinoid
once the car is rolling the egr vaccum solinoid is on
and the vaccum leak causeing a high idle!

 

doh i had a brain fart!

i just realized how silly i was.

ok so back to the drawing board...

blackitr, i understand i have my idle set higher than normal but what im not understanding is that this rolling idle is 500rpms higher than my standing idle. doesnt that seem a bit extreme?