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Old 11-18-2008, 11:19 PM   #21
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Why is your fuel VE Table and your AFR Targets table 15 x 15?

Also, where are you finding that Warmup Curve editor?

Your percentages for the warmup are also really small, mine are ridiculous right now to get down to 11:1

The accel wizard numbers are also much much higher then what I have.
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Old 11-18-2008, 11:31 PM   #22
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Quote:
Originally Posted by Saml01 View Post
Why is your fuel VE Table and your AFR Targets table 15 x 15?

Also, where are you finding that Warmup Curve editor?

Your percentages for the warmup are also really small, mine are ridiculous right now to get down to 11:1

The accel wizard numbers are also much much higher then what I have.
The ve table is 16x16. The Spark and AFR tables are 12x12. None are 15x15...

I go into megatune and click "startup/idle" and then click warm up enrichment.

Probably cause you don't idle at 11:1 when it's warmed up.

Also, I'm MS2E, hence why my ve table is big and the software is different.
And I have a different engine than you, so that's probably why my settings are different.
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Old 11-18-2008, 11:40 PM   #23
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^ You gotta tell me these things man. Im like "woh" over here. But that was my next guess.


I really need to sort this **** out, I gotta try and switch the timing from 17 to 10 and see which idles better when cold.


Will post back with results, thanks for nursing me through this. I really appreciate the time.
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Old 11-20-2008, 12:03 PM   #24
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This is weird as hell.

The winter before the turbo with megasquirt, idling in freezing temps was dead stable. Since then I have not touched my warmup enrichments, or idle timing. Soon as the temps dropped, I started having these weird issues. My warmup bin at 140 is like 150%, and its getting me to 12:1 maybe. Really horrendous idle, as it gets warmer it gets better. Once passed 160* its totally fine.

I have two theories now.

Either its a weak spark. My thoughts are if it was weak then id probably have problems at WOT at 14psi. Id imagine weak spark at idle would be even more prevalent under load.

TOO much fuel during warmup, The car reaks of unburned gasoline when it sits their warming up, like really nasty. Im thinking of chopping the WE back to what they were and starting again.

This is COP setup too. Running a 4ms dwell for crank and run, because any lower and the car doesn't start. So I have been running 4ms ever since installed them with a .5ms discharge.

Could the spark plugs be due for a change? I think, again, it would be more evident under load.

Its pretty freaky, it idles but its just all over the ******* place.

Also, I haven't yet experimented thoroughly, but it seems the car warms up more steadily with the headlights on? No definitive tests yet, so its a big MAYBE on this point.
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Old 11-21-2008, 02:23 PM   #25
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So I was just doing some serious brain storming.

My car idles great when warm, at that point the engine is at 10* of timing because the map has dropped. But when its cold started, its warming up with almost 16* because the cell above the 10* is 18*. So its scaling somewhere in there.

Would lowering timing to 10* during warmup help with idle quality?
Is there anyway to pull timing based on engine temp?

I am going to try this tonight but id like to hear some thoughts.
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Old 11-21-2008, 04:23 PM   #26
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Usually, you would add spark advance when the engine is cold. You can adjust timing based on temperature from the Spark -> IAT / Clt Related Ignition screen.
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Old 11-21-2008, 04:54 PM   #27
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Sam..... I don't know what to tell you. Post your msq and I'll look at it.
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Old 11-21-2008, 04:55 PM   #28
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Oh yeah. Fired up my car at 31*F a couple days ago. Purs at 800 now. Dead smooth and very strong. No hickups or nothing. Sounds like it's completely warmed up. I mean so smooth, it's scary.
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Old 11-22-2008, 01:08 AM   #29
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Quote:
Originally Posted by patsmx5 View Post
Sam..... I don't know what to tell you. Post your msq and I'll look at it.
Ill have to take you up on that, I really dont know what else to try. Ill post it tomorrow, I left the laptop in the car.


What I know now for a fact, after exactly 140F the idle becomes dead stable.

Retarding the timing to 10* did help make it a little better when starting totally cold.

Quote:
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Usually, you would add spark advance when the engine is cold. You can adjust timing based on temperature from the Spark -> IAT / Clt Related Ignition screen.
Can you explain the logic behind that please?
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Old 11-22-2008, 05:11 PM   #30
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OK. So i definitely get an improvement idling closer to 20* when cold. A very big improvement in fact. I left it there for now, and I decreased my idle rpm with the idle screw once it was warm. Tomorrow ill see what happens from a full cold start.
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Old 11-23-2008, 11:13 PM   #31
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Ok. Seriously.

Why are my warmup bins so god damn high. 150% in the 140* temp.

Could this be the sign of a failing fuel pump? I have never had to have them so high.

My AIT correction for heat soak are also ridiculous and almost have no effect.
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Old 11-24-2008, 01:56 AM   #32
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post your msq and i'll look at it.
+1
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Old 11-24-2008, 10:21 PM   #33
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+1
Please take a look and tell me what you think.

Last edited by Saml01; 11-27-2008 at 07:12 PM.
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Old 11-26-2008, 03:48 PM   #34
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Any ideas Pat?
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Old 11-26-2008, 04:09 PM   #35
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I'm gonna say you are probably having an ignition problem. I see you're running a lot of dwell, and I remember reading before you had a miss when running "normal" values for dwell. I suspect this is your problem. How much gap are you running on the plugs? Try gapping them to .020".
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Old 11-26-2008, 05:48 PM   #36
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Originally Posted by patsmx5 View Post
I'm gonna say you are probably having an ignition problem. I see you're running a lot of dwell, and I remember reading before you had a miss when running "normal" values for dwell. I suspect this is your problem. How much gap are you running on the plugs? Try gapping them to .020".


The car would not run with values of 3.5/2.5 when I first put in the COP's. Ran spot on with 4.5/4.5 which was what I ran for factory coils. It also ran like this, spot on, through last winter, which was pre turbo.

I also am running the stock gap.

Ill play around with it just a little bit more, but if its truly not solvable im gonna find some new coils. Changing spark gap is not a solution.
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Old 11-26-2008, 05:53 PM   #37
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Originally Posted by Saml01 View Post
The car would not run with values of 3.5/2.5 when I first put in the COP's. Ran spot on with 4.5/4.5 which was what I ran for factory coils. It also ran like this, spot on, through last winter, which was pre turbo.

I also am running the stock gap.

Ill play around with it just a little bit more, but if its truly not solvable im gonna find some new coils. Changing spark gap is not a solution.
Run .020" to see if it has an affect. IE-we're trying to diagnose the real problem. So do it anyways to see if perhaps this is an ignition related problem It won't cost you anything but 5 minutes time. And what's it gonna hurt to run less gap anyways?
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Old 11-26-2008, 09:07 PM   #38
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Quote:
Originally Posted by patsmx5 View Post
Run .020" to see if it has an affect. IE-we're trying to diagnose the real problem. So do it anyways to see if perhaps this is an ignition related problem It won't cost you anything but 5 minutes time. And what's it gonna hurt to run less gap anyways?
If it doesnt hurt to run less gap then why did everyone jump on the bandwagon to go to COP's to run a bigger gap?

Ill try it, and report back.
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Old 11-26-2008, 09:13 PM   #39
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If it doesnt hurt to run less gap then why did everyone jump on the bandwagon to go to COP's to run a bigger gap?

Ill try it, and report back.
Same reason everyone buys a dual feed fuel rail.
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Old 11-26-2008, 09:27 PM   #40
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Same reason everyone buys a dual feed fuel rail.
lol, except the dual feed rail was proved useless. While it was proven that the COP's provide stronger spark then the factory coils.

If I find some plug wires this weekend, ill connect my old coils and see what happens.

Better. question. How often should plugs be replaced since the engine is now turbocharged?

I haven't replaced mine in 4k miles since I went turbo. Running regular coppers.

Last edited by Saml01; 11-26-2008 at 09:41 PM.
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