Trying to test ISC because of bad idle. Problems.

[96gstdsm]

Well I have not driven my car for a while now, but before it was always having idle problems and all so I figured it was a bad ISC so I went to test it today and I really don't know whats going on. I must be doing something wrong.
I have a multimeter and when testing the pins, the multimeter number just goes all crazy up and down and then stops back down at 0. I have it set at 2000k. It will like go 450, 794, -14, etc (just random examples) and then always stops at -000. Am I testing it incorrectly? Or is this how it acts when the ISC is in fact damaged? please any advice would be great as I am looking to sell this shortly, and would rather sell it with a good idle.

 

[96gstdsm]

Anyone with knowledge on how to correctly test it if I am doing it wrong? I just put the two pins from the multimeter on 1-2 and then 2-3 etc. Each test the numbers just went crazy and showed nothing. Never settled on anything except -000 after a few seconds of bouncing around. Car stalls constantly so I think this is the issue. The rpm's will jump up and down for a while and then eventually die. The only way it was driveable for a little while was by adjusting the BIS. So I'm sure adjusting that throws the ISC out of wack but I would think it would still steadily read something correct?

 

[winterftbl]

IF it hits tripls 000. Then that means it is bad. If your going to just sell it then you might as well unplug the isc and adjust your idle with the biss screw. Is your check engine light on?

 

[96gstdsm]

IF it hits tripls 000. Then that means it is bad. If your going to just sell it then you might as well unplug the isc and adjust your idle with the biss screw. Is your check engine light on?

Well my CEL is always on because I have no cat, no emissions stuff aggressive cam's and also a 6 bolt swap, but I haven't seen the ISC CEL that I can remember. Was mostly egr and misfire from the 6 bolt swap I think. So 000 definitely means the ISC is bad?

 

[BoostedinSoFla]

http://www.dsmtuners.com/forums/newbie-forum/273307-idle-speed-control.html#post151306992

 

[96gstdsm]

Well I know how to test it but I want to make sure that the readings I got were correct if it has gone bad. One person said if it reads 000 across the board than it is bad. Can anyone else confirm that the readings I got were in fact from a bad ISC and not somehow testing incorrectly?

 

[steve]

Set your meter on the right setting for the expected measurements. If you have a 200 ohm scale (not 200k ohms or 2000k) use it. Make sure your not touching the probes together while your measuring, it can be tight in the connector. Also make sure you know the difference between the way your meter displays a short (the probes touching) and an open (the probes not touching). make sure you have good readings, the cheaper digital meters might need some time to settle.

 

[BoostedinSoFla]

Well I know how to test it but I want to make sure that the readings I got were correct if it has gone bad. One person said if it reads 000 across the board than it is bad. Can anyone else confirm that the readings I got were in fact from a bad ISC and not somehow testing incorrectly?

Did you even read the link that I posted? It has everything including how to tell when it's bad. Go back and read again..

 

[96gstdsm]

I did read it. It only says that if the numbers are higher then you have a busted ISC. My numbers aren't higher but jump all around and then settle at -000. It is not showing any set number just goes all crazy.

 

[BoostedinSoFla]

I did read it. It only says that if the numbers are higher then you have a busted ISC. My numbers aren't higher but jump all around and then settle at -000. It is not showing any set number just goes all crazy.

Do you have your multimeter set to the lowest Ohm setting?

 

[96gstdsm]

Do you have your multimeter set to the lowest Ohm setting?

I'm at work right now but yesterday when I set it at 200 it would only beep and do nothing else. That confused me. I will try again today set at 200 and see if the same thing happens.


PS you got that heat shield from me right? Looks good.

 

[BoostedinSoFla]

PS you got that heat shield from me right? Looks good.

Yeah, thanks man. Check back and let me know.

 

[96gstdsm]

OK so I tested it again and it showed 37 ohms I believe so the ISC should be bad. I removed the ISC and the rpm's when idling would jump up and down really fast unless I turned the BIS all the way in and then it would idle around 2,000 rpm's. I thought when the ISC was removed that it would idle a little off sometimes but nothing crazy like that. Would just drop low when the clutch was put in or AC etc. Am I wrong there? Would this continue like this with it not attached? Anything else it could be if this is not what should happen with the ISC disconnected?

 

[steve]

OK so I tested it again and it showed 37 ohms I believe so the ISC should be bad.

No not by that reading. It's a little higher than spec for a metal cased ISC but just about what would be expected from a black plastic cased one. Bad would be resistances less than 20 ohms or greater than 100 ohms.

I removed the ISC and the rpm's when idling would jump up and down really fast unless I turned the BIS all the way in and then it would idle around 2,000 rpm's.

Removed it how? Not taken out of the throttle body, that would be a huge air leak. Just unplugged right?

I thought when the ISC was removed that it would idle a little off sometimes but nothing crazy like that. Would just drop low when the clutch was put in or AC etc. Am I wrong there? Would this continue like this with it not attached? Anything else it could be if this is not what should happen with the ISC disconnected?

The result depends on where the ISC pintle was when you unplugged it. If it was in it's default position then the car might surge until warm when the FIAV closes since normally tje ISC would be closed shortly after starting and then open back up as the FIAV closes.

If the pintle was closed the car should warm up fine but want to die once it was warm unless you open the BISS up. If it was open more than the default position then the car might idle surge all the time like you described until you close down the BISS and you might not be able to reduce the bypass air enough with the BISS to get the idle speed under control.

 

[96gstdsm]

No not by that reading. It's a little higher than spec for a metal cased ISC but just about what would be expected from a black plastic cased one. Bad would be resistances less than 20 ohms or greater than 100 ohms.


Removed it how? Not taken out of the throttle body, that would be a huge air leak. Just unplugged right?



The result depends on where the ISC pintle was when you unplugged it. If it was in it's default position then the car might surge until warm when the FIAV closes since normally tje ISC would be closed shortly after starting and then open back up as the FIAV closes.

If the pintle was closed the car should warm up fine but want to die once it was warm unless you open the BISS up. If it was open more than the default position then the car might idle surge all the time like you described until you close down the BISS and you might not be able to reduce the bypass air enough with the BISS to get the idle speed under control.

I have the coolant blocked off to the throttle body could that cause any problems?
Yeah the ISC was just unplugged not disconnected.
Not really sure what my next steps can be to try to get this thing to idle well. It does have 272 cams so never going to be perfect but shouldn't jump around so crazy at all. I have a new BIS o ring so shouldn't be leaking there anymore if that would even effect anything.
Once the car did warm up stalled a couple of times after I took it for a spin last night.
(fwd with a bunch of power really sucks, could not get traction till like 50mph haha) cold out though.
So what are my options now to check whats happening? It has been idling poorly ever since my 6 bolt swap and all. The guy who put the engine in said that it might be the ISC motor but I guess thats not it. Would the base idle have to be reset or something for it to idle properly? I don't have much experience with idling problems.

 

[96gstdsm]

Anyone with a little more insight on where I should go next with it?

 

[steve]

I have the coolant blocked off to the throttle body could that cause any problems?

Yes, blocking off the TB coolant means that the FIAV will never close. That will cause problems.

Yeah the ISC was just unplugged not disconnected.

Plug it back in. Your resistance measurements imply that it's not shorted and likely works.

Not really sure what my next steps can be to try to get this thing to idle well. It does have 272 cams so never going to be perfect but shouldn't jump around so crazy at all.
So what are my options now to check whats happening?

It has been idling poorly ever since my 6 bolt swap and all. The guy who put the engine in said that it might be the ISC motor but I guess thats not it. Would the base idle have to be reset or something for it to idle properly? I don't have much experience with idling problems.

Hook the throttle coolant hoses back up, clean the throttle body, pressure test for leaks, check your IPS operation, and set the BISS and timing. Since your talking about a six bolt swap which throttle body are you using and how is the IPS set up? 1G IPS or 2G?

You never really said what it is that your trying to fix. I assume at this point you have idle surge and that after you disconnected the ISC it started stalling but after almost 5 years of guessing what people are thinking the crystal ball is running low on boost fluid.

 

[96gstdsm]

Yes, blocking off the TB coolant means that the FIAV will never close. That will cause problems.


Plug it back in. Your resistance measurements imply that it's not shorted and likely works.



Hook the throttle coolant hoses back up, clean the throttle body, pressure test for leaks, check your IPS operation, and set the BISS and timing. Since your talking about a six bolt swap which throttle body are you using and how is the IPS set up? 1G IPS or 2G?

You never really said what it is that your trying to fix. I assume at this point you have idle surge and that after you disconnected the ISC it started stalling but after almost 5 years of guessing what people are thinking the crystal ball is running low on boost fluid.

What is the benefit of blocking the coolant off? I did not want it blocked off but got my car back that way.
I am using a 2g head on a 6 bolt block so I have the 2g throttle body.
I am trying to fix the idle so that it will stay steady and not too high or low.
Even with the ISC in it constantly has idle surge and stalls out quite a bit.
Running coolant back through the throttle body is an easy reversal? Not quite sure how to go about that.

Basically I am looking to sell this car but it has a few little kinks I want to fix first so I can get at least some of the money I put into this car.

 

[steve]

What is the benefit of blocking the coolant off?

People think that it will help keep the intake temps down but the heat transfer is minimal and the drawbacks from bypassing are significant.

I posted the adjustment procedure for the TPS on a 2G (How to set the IPS switch point). You need to make sure it's working or the ECU won't even try to maintain the idle speed.

 

[96gstdsm]

People think that it will help keep the intake temps down but the heat transfer is minimal and the drawbacks from bypassing are significant.

I posted the adjustment procedure for the TPS on a 2G (How to set the IPS switch point). You need to make sure it's working or the ECU won't even try to maintain the idle speed.

I tested the TPS when I had my ecu+ installed. It was working correctly. Can't remember the volts or whatever it is measured by but when I checked it was the correct numbers.

 

[steve]

I'm referring to making sure that the IPS is working correctly since that's how you set a 2G TPS.

 

[96gstdsm]

I'm referring to making sure that the IPS is working correctly since that's how you set a 2G TPS.

How do I check the IPS?
I am trying to revive my eclipse from it's grave now.
Really missing the turbo power and torque. don't have that with my S2000 I bought. Love it non the less even though it's a Honda haha. Think my battery died or at least needs a trickle charge since it's been sitting for 6 months or so now.

For overheating problems due to a fmic. Has an upgraded radiator cured the problem for anyone?

 

[steve]

How do I check the IPS?

Here's the procedure for setting the 2G IPS. Testing would involved check to make sure that it's set correctly.

From the RRE page:

Closed TP Switch and TP Sensor Adjustment [2G]

1. Disconnect the connector of the TPS.
2. Connect ohm meter between terminals 3 and 4.
3. Insert a feeler gauge with thickness 0.45mm (.0177 in.) between the throttle stop and the throttle lever.
[Fold a piece of paper in half 4 times if you don't have the feeler -Ed.]
4. Loosen the TPS mounting bolts. Turn the TPS all the way counter
clockwise.
5. Check for continuity in this condition.
6. Slowly turn the TPS clockwise until the point where continuity and
non-continuity is found (pins 3 and 4).
7. Tighten the TPS mounting bolts.
8. Check the voltage between pins 2 and 4 of the TPS with the ignition
switch on, but the engine not started.
9. Standard value: 400 - 1000 mV
[Measure at the ECU pins or on your SAFC]
10. Remove the feeler gauge.

 

[96gstdsm]

Alright well I have been really busy and haven't had much time to work on it. Got it running today after sitting for about 6 months now. Just needed a new battery. Primed the engine a few times before cranking it and it started right up first try with no smoke really. Idle was fine at first. I guess I have a leak on one of the oil lines to the turbo. There is a little bit of smoke coming from under the turbo. (new big 16g) When I revved it up a bit, it would shoot out more smoke.
Once it really warmed up after revving it up the idle died right out. When it was cold it would stay fine.
I will work on getting the coolant lines hooked back up to the throttle body. Gotta replace all vacuum lines now too. Place that installed my engine put real crappy ones in.
Also I'll test the IPS when I can. From no longer having the idle surge but just stalling once warmed up, does that lead anyone to believe one most likely cause over another?

 

[redtsi252]

Block off the ISC and FIAV and call it a day