Help with Idle Control VW

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doublejoe
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Help with Idle Control VW

Post by doublejoe »

Hello members,

I have been fighting with idle control.

High revving or, too low, ???

What can I show you all that can help with getting this project idling.

I am using MS3X.

Any help would be great.
Matt Cramer
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Re: Help with Idle Control VW

Post by Matt Cramer »

:msq:
Matt Cramer -1966 Dodge Dart slant six running on MS3X
doublejoe
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Re: Help with Idle Control VW

Post by doublejoe »

Yes
Sorry.
Here is my current msq.
Matt Cramer
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Re: Help with Idle Control VW

Post by Matt Cramer »

...and the data log?
Matt Cramer -1966 Dodge Dart slant six running on MS3X
doublejoe
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Re: Help with Idle Control VW

Post by doublejoe »

Here is a Data Log.
mind you all, that when the car is started it has a high idle. I believe that is the way that i have it set to do. BUT, when in warm up, when i blip the throttle it hangs at the last point of rev rpm.???

In the log you can see where it drops back down, I AM Doing this by hand to close the throttle body.
Blip the throttle, and it hangs high???

If the log doesnt show what is need to help me out. Just mention what you want logged, and i can log again.

I am a noob to this forum and how you guy all want to see what my data.

Again, thanks for the support.
Matt Cramer
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Re: Help with Idle Control VW

Post by Matt Cramer »

Here are some of the things that stand out to me.

1. The warmup enrichment curve ends at 102.6 degrees F. This is rather unusual. Usually engines still need more fuel for a while longer during warmup.

2. The engine appears never to have reached operating temperature in that log. Unless this is a boat with lakewater cooling. And even then I'm not sure.

3. You're trying to idle too lean. This may be tied in to the two above notes. Get the AFR dialed in with the engine hot, then see if it's correct on a cold start.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Paul_VR6
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Re: Help with Idle Control VW

Post by Paul_VR6 »

What *exact* idle valve?
-Paul
1992 Corrado SLC 3.6 VR6 11.38@120 - MS3 Pro Ultimate - Microsquirt I/O - Can EGT - Racepak IQ3s
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doublejoe
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Re: Help with Idle Control VW

Post by doublejoe »

Paul_VR6 wrote:What *exact* idle valve?

This Valve is off of a 1998 Audi A4 1.8t. Drive By Cable.
I believe that this is the same valve as the MK3 VW 2.0 x-flow engine throttle body.
doublejoe
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Re: Help with Idle Control VW

Post by doublejoe »

Matt Cramer wrote:Here are some of the things that stand out to me.

1. The warmup enrichment curve ends at 102.6 degrees F. This is rather unusual. Usually engines still need more fuel for a while longer during warmup.

2. The engine appears never to have reached operating temperature in that log. Unless this is a boat with lakewater cooling. And even then I'm not sure.

3. You're trying to idle too lean. This may be tied in to the two above notes. Get the AFR dialed in with the engine hot, then see if it's correct on a cold start.

Okay,
I followed your advise.

I took the "Lake water" out of the equation. LOL This is a Car not a Boat. :lol:
My log was only to show you all the high reving and low idle issues.

So now i made a few changes to what you had mentioned and did a full datalog until the fans kicked on at 180*ish.


In this log towards the end of the log, I reved it and the idle hung so i physically lowered the idle by hand. Then it would idle too low, then rev up past my set point.

Please review it and let me know what i am doing wrong.

Much appreciated, :RTFM:
Joey
prof315
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Re: Help with Idle Control VW

Post by prof315 »

Are you using the throttle body with the integrated Idle valve? If so your results with it will be mediocre at best. While it "works" with PWM it was designed for a different type of control altogether. I have had my best luck wiring it backwards and running inverted from "limp in" to fully closed.
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doublejoe
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Re: Help with Idle Control VW

Post by doublejoe »

prof315 wrote:Are you using the throttle body with the integrated Idle valve? If so your results with it will be mediocre at best. While it "works" with PWM it was designed for a different type of control altogether. I have had my best luck wiring it backwards and running inverted from "limp in" to fully closed.
How do you mean wire it backwards?
Paul_VR6
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Re: Help with Idle Control VW

Post by Paul_VR6 »

Swap the polarity at the valve
-Paul
1992 Corrado SLC 3.6 VR6 11.38@120 - MS3 Pro Ultimate - Microsquirt I/O - Can EGT - Racepak IQ3s
kptuned.com - Megasquirting the World! Megasquirt Sales, Service, Tuning and More!
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doublejoe
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Re: Help with Idle Control VW

Post by doublejoe »

UPDATE!

I have since gone to a 2 wire VW ISV.

I still have idle bounce during WUE.

Can you guys please help with my settings?
Paul_VR6
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Re: Help with Idle Control VW

Post by Paul_VR6 »

Start with that valve in closed loop. Around 33% warm will be a good start. Smooth fuel and timing around idle to get rid of bouncing. Then enable closed loop idle.
-Paul
1992 Corrado SLC 3.6 VR6 11.38@120 - MS3 Pro Ultimate - Microsquirt I/O - Can EGT - Racepak IQ3s
kptuned.com - Megasquirting the World! Megasquirt Sales, Service, Tuning and More!
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SwedCharger-67
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Re: Help with Idle Control VW

Post by SwedCharger-67 »

I think you need to tune both the Idle VE table and the VE table itself, you have big jumps in fuel when going in and out of Closed Loop Idle during the oscillation.
The Idle VE Table should have higher VE values at higher MAP values since the Idle Valve opens to let more air in.
Martin, Sweden
Mopar 512 cui, 8.4 liters, high compression, fuel E85, full sequential control by MS3X, burning rubber just blipping the throttle... :D
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