M30B30 high kpa idle

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E32
Posts: 10
Joined: Sep 18, 2010 7:09 PM

M30B30 high kpa idle

Post by E32 »

Hi,

Just getting my turbo install going:

Image

My kpa at idle is just above 60, car is idling at 900 RPM, shouldn't this be in the 40's?

ECU is a VEMS, the car has been on MS2 with the same issue, head has just been restored following a blown head gasket.
turbodan
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Joined: Jan 09, 2007 10:19 PM

Post by turbodan »

Does more ignition advance help?

M30's dont seem to pull as much vacuum at idle as M20's. Its probably nothing to worry about. As long as the engine is in good condition I'd say its normal.
Jeremy
Beamter
Beamter
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Location: Connecticut

Post by Jeremy »

60 isn't terribly normal. I don't recall exactly what MAP mine idles at off the top of my head, but I'm fairly certain it's in the low 30s.
Scottinva
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Location: Norfolk, Virginia

Post by Scottinva »

While I am not turbo, my N/A m30b34 idles at 32KPA. I idle at 22 degrees at 900rpm. It's butter smooth. Do you have a non stock camshaft?
marc79euro645
Posts: 513
Joined: Dec 08, 2008 11:33 PM

Post by marc79euro645 »

cam timing may be off a tooth,easy to do
good luck
marc
E32
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Joined: Sep 18, 2010 7:09 PM

Post by E32 »

Thanks guys,

Cam has been set 2 times both following firstfives.org, would a tooth to the wrong side result in higher Kpa?

We'll try higher numbers in the idle setting, is 22 really normal for a M30?
Shadow
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Post by Shadow »

27* and 800rpm puts me at 35kpa.

I had it good at 19* and 38kpa, but for some reason
the engine needed more advance as time went by.
Maybe the key on the wheel is bending. idk.

Just keep advancing until it stops getting better.
60kpa is almost ready to die it seems.
Jeremy
Beamter
Beamter
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Post by Jeremy »

Verify your timing marks. You might not be getting as much advance as you think.
E32
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Joined: Sep 18, 2010 7:09 PM

Post by E32 »

Ok, we're going to try advancing it step by step later today, just need to get the exhaust mounted first.
E32
Posts: 10
Joined: Sep 18, 2010 7:09 PM

Post by E32 »

Scottinva wrote:While I am not turbo, my N/A m30b34 idles at 32KPA. I idle at 22 degrees at 900rpm. It's butter smooth. Do you have a non stock camshaft?
I believe it's stock. It was repaired shortly after I bought the car, and I've heard no mention of it being anything but stock.
E32
Posts: 10
Joined: Sep 18, 2010 7:09 PM

Post by E32 »

Tried changing the advance from 14.5 - 25. Which gave zero difference, I'm wondering if we actually have proper control over the VEMS...?
iXer
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Post by iXer »

E32: Send me a PM and we can discuss your VEMS installation, I could review your config file.
marc79euro645
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Joined: Dec 08, 2008 11:33 PM

Post by marc79euro645 »

my m106 idles at 20*@ 42kpa @ 900 rpm when warm
E32
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Joined: Sep 18, 2010 7:09 PM

Post by E32 »

Got great advice from Mathias, will try them in a few days time and report back.
E32
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Joined: Sep 18, 2010 7:09 PM

Post by E32 »

http://www.youtube.com/watch?v=Lnq_ZHgxDTI

This the current running status of my idle problems.

When it goes to 2K, that's me. You can see it dips a bit low afterwards.
marc79euro645
Posts: 513
Joined: Dec 08, 2008 11:33 PM

Post by marc79euro645 »

you have to flatten out the area of your ve map at idle
for injection
& also the same for ignition (if your using vems for that)
I encountered this tuning with megasquirt.
if you view it in 3d the idle area would be a flat plateau
marc
E32
Posts: 10
Joined: Sep 18, 2010 7:09 PM

Post by E32 »

marc79euro645 wrote:you have to flatten out the area of your ve map at idle
for injection
& also the same for ignition (if your using vems for that)
I encountered this tuning with megasquirt.
if you view it in 3d the idle area would be a flat plateau
marc
We've tried that, but speaking to Mattias, I'm beginning to understand, we are in deeper problems, than originally envisioned... :lol:
E32
Posts: 10
Joined: Sep 18, 2010 7:09 PM

Post by E32 »

E32 wrote:http://www.youtube.com/watch?v=Lnq_ZHgxDTI

This the current running status of my idle problems.

When it goes to 2K, that's me. You can see it dips a bit low afterwards.

Solved!

Wrong fuel cut settings (60 Kpa), idle doesn't hunt anymore.
E32
Posts: 10
Joined: Sep 18, 2010 7:09 PM

Post by E32 »

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