High idle with timing change

zenboy99

Founding Member

May 12, 2002

2,212

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47

Madison, WI

May 31, 2006

#1

• May 31, 2006

• #1

So my idle was jumping around alot, looked under the hood and found that the distributor was loose. tightened it down and set the timing to 10 deg with a timing light.

Now my idle is at 1250rpm, Tweecer reads a steady 20 deg of timing, doesn't change at all.

I've adjusted inj breakpoint, high/low slope, TB airflow, MAF curve all before this and everything was fine. Spout is back in too and no vacuum leaks are detected.

Any suggestions?

 

vristang

15 Year Member

Mar 31, 2005

4,933

101

124

Seattle

May 31, 2006

#2

• May 31, 2006

• #2

You may just have to reset idle?
I wouldn't think timing would have that much of an impact though.

What do you have idle set to in CalEdit?

jason

 

SVTCobra306

New Member

Oct 22, 2005

170

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0

Ft. Bragg, NC

May 31, 2006

#3

• May 31, 2006

• #3

Your timing stays at 20 on Calcon regardless of RPM/throttle input is what your saying? Or does it stay at 20 at 1250 RPM?

Maybe the TPS is reading a part open throttle and going into the timing table... what voltage are you getting from the TPS?

 

zenboy99

Founding Member

May 12, 2002

2,212

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47

Madison, WI

Jun 1, 2006

#4

• Jun 1, 2006

• #4

TPS voltage is .975

Timing stays right at 20 degrees at idle, but then changes once I open up the throttle and drive around.

Idle is set at 900 in the Tweecer.

This sucks because I have a ton of landscaping to do at my house and we have a mobile dyno coming into town this weekend, so I'd like to figure this out asap.

 

broken_joke

Member

Nov 24, 2004

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carriere, ms

Jun 1, 2006

#5

• Jun 1, 2006

• #5

i had a similar problem with idle and the isc cl above idle rpm scalar was set kinda high. hope it helps.
jake

 

zenboy99

Founding Member

May 12, 2002

2,212

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47

Madison, WI

Jun 1, 2006

#6

• Jun 1, 2006

• #6

broken_joke said:

i had a similar problem with idle and the isc cl above idle rpm scalar was set kinda high. hope it helps.
jake

Click to expand...

Cool, do you remember the values? I don't have my Tweecer with me.

 

broken_joke

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Nov 24, 2004

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carriere, ms

Jun 1, 2006

#7

• Jun 1, 2006

• #7

mine is set at 150. i think it adds that number to your idle?
jake

 

zenboy99

Founding Member

May 12, 2002

2,212

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47

Madison, WI

Jun 1, 2006

#8

• Jun 1, 2006

• #8

I was thinking that raised the idle 150rpm above when you're coasting?

 

broken_joke

Member

Nov 24, 2004

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carriere, ms

Jun 1, 2006

#9

• Jun 1, 2006

• #9

i just went outside turned the car on out of curiosity and tried messing with that scalar and it didn't do anything. i tried changing all the rpm scalars and it didn't do anything? it stayed and idled right at 1000? i took the car out of cl loop and everything i might have been high on exhaust fumes when i thought that scalar helped? sorry

 

final5-0

Mustang Master

Apr 6, 2003

6,817

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DFW Texas

Jun 1, 2006

#10

• Jun 1, 2006

• #10

See if a pcm reset will help Chad

If not, look at the neutral idle airflow functions.

The may need to be raised a bit.

Grady

 

zenboy99

Founding Member

May 12, 2002

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Madison, WI

Jun 21, 2006

#11

• Jun 21, 2006

• #11

reset the computer twice and checked timing twice. Still have the high idle problem.

In calcon what do you guys normally see for timing values at idle?

 

final5-0

Mustang Master

Apr 6, 2003

6,817

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DFW Texas

Jun 21, 2006

#12

• Jun 21, 2006

• #12

It is normal to see the spark jump around at idle as that is the pcm doing its thing to obtain a steady idle.

The isc scalar is supposed to be a bit higher than the value you have for the normal idle.

IIRC, it is in the range of 100 to 150 higher.

This range is necessary for the isc to be able to do its thing.

Grady