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Need help with a coldstart tune


Reemen

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Hello

Im new to this forum, and i was wondering if anybody could help me with coldstarting my 2jz.
I attached a Log file and my Map.
My tuning knowledge is on the basic level, so please bear with me.

So what im struggeling with is getting my car above 4-500 rpm on startup. 
The problem is only when the car is cold. The idle is fine when its warm.
I tried playing around with the post start enrichment and warm up enrichment but no matter what i do i cant seem to get it above 500rpm without using the gas pedal.

Thank you in advance!

I got Bosch 2000cc injectors and 264 cams

coldstart.llg 95oktan børge fikset.pclr

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Get the car to normal operating temperature and adjust your main fuel table so the AFRs are 14 - 14.7 during idle. (make sure all fuel corrections are done)

F12 will show you if there are any trims that are on.  

Then smooth the fuel table back around that area.

 

Next day start the engine and now you can play with your Warm Up Enrichment.

At start I have my engine running 13.8 - 14. 

Adjust your warm up enrichment so it reaches your idle AFRs, once ECT reaches your operating temps. (158 F in your case)

 

HP Academy and Evans Performance  Academy are a great resource if you want to learn more. 

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4 minutes ago, remski2 said:

Get the car to normal operating temperature and adjust your main fuel table so the AFRs are 14 - 14.7 during idle. (make sure all fuel corrections are done)

F12 will show you if there are any trims that are on.  

Then smooth the fuel table back around that area.

 

Next day start the engine and now you can play with your Warm Up Enrichment.

At start I have my engine running 13.8 - 14. 

Adjust your warm up enrichment so it reaches your idle AFRs, once ECT reaches your operating temps. (158 F in your case)

 

HP Academy and Evans Performance  Academy are a great resource if you want to learn more. 

Thank you :)
The car idles fine when its warm. The AFR is stable around 14,7.
But how do i raise the RPMs during startup? 
Without me helping on the throttle it bearly goes above 500 before dying out again.
Is this all because of the fuel table?

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There are several problems with your idle setup.  The main one being that the keep alive time is set to zero so the idle valve cannot reset after the engine is turned off.  So next time you start the engine the ecu has no idea where the idle valve position is so it cant move it to the correct position.

So set the ECU hold power/keep alive time to  10 seconds.  Your idle base position table will then probably need some re-tuning.  Do us another cold start log after changing the keep alive time (ignition needs to be turned off for 10 seconds before restarting after changing this setting).  

wLpCZM6.png

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11 hours ago, Adamw said:

There are several problems with your idle setup.  The main one being that the keep alive time is set to zero so the idle valve cannot reset after the engine is turned off.  So next time you start the engine the ecu has no idea where the idle valve position is so it cant move it to the correct position.

So set the ECU hold power/keep alive time to  10 seconds.  Your idle base position table will then probably need some re-tuning.  Do us another cold start log after changing the keep alive time (ignition needs to be turned off for 10 seconds before restarting after changing this setting).  

wLpCZM6.png


Thank you for the reply Adam :)

So now i have changed the hold power to 10 sec, and attached a new log for you.
The car managed to stay alive at around 500rpm quite a while this time, but i wont go any higher without me using the throttle. 
Still runs really rich, so i quess i have to take quite abit away from the start up/warm up enrichments?

coldstart3.llg

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Ok, It's odd that the valve needs to be open so far, usually these engines are at around 150 steps for a cold start yours is at 50 and still appears to need a lot less.  So you can try dropping the min clamp to about 25 to see if that helps, I dont like going much lower than that as it will bottom out and lose position.  If that doesnt help I think you are going to have to open the throttle stop a little to allow the idle valve to work in a more normal position.

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28 minutes ago, Adamw said:

Ok, It's odd that the valve needs to be open so far, usually these engines are at around 150 steps for a cold start yours is at 50 and still appears to need a lot less.  So you can try dropping the min clamp to about 25 to see if that helps, I dont like going much lower than that as it will bottom out and lose position.  If that doesnt help I think you are going to have to open the throttle stop a little to allow the idle valve to work in a more normal position.

I tried setting it to min clamp 25 and attached another log, didnt seem to help anything.
How do i open the throttle stop?

coldstart minclamp25.llg

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I just had another thought.  I cant remember how difficult the 2J idle valve is to get at, but if it is not too bad could you pull the motor out, and then with it still plugged in switch the ign on/off to check it is actually moving.  When you turn ign off it should wind all the way in, then back out a little.  Also check the mating half of the valve body is reasonably clean so it is not jamming.

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21 hours ago, Adamw said:

I just had another thought.  I cant remember how difficult the 2J idle valve is to get at, but if it is not too bad could you pull the motor out, and then with it still plugged in switch the ign on/off to check it is actually moving.  When you turn ign off it should wind all the way in, then back out a little.  Also check the mating half of the valve body is reasonably clean so it is not jamming.

So i didnt pull out the idle valve because my power steering reservoir was in the way. But i did try to manually increase my idle valve on the throttle body just to see how the car would react.
And i did a complete log from cold to hot. The car started easily and didnt die out, but the rpm is all over the place, espessially when the ECT reaches 40 degrees. Thats when the idle valve starts mooving, so maybe thats a sign that its working?
Would you mind looking over the log and see if you can find anything unusual? 
I had to screw the idle valve on the throttle body back down because the car wouldn't idle below 1500rpm after it was hot, so it didnt solve any issues.

coldstart full.llg

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18 hours ago, Adamw said:

From that log I would say the idle valve is not working at all.  Most likely is has either failed electrically or is gummed up.  The test I suggested earlier will confirm.

You were completely right.. I took out the idle valve and it turns out the previous owner had blocked it off with an aluminium plate. 
So i removed that and put it back together and tried starting the engine. It immediately revd above 4000rpm so i shut the engine off again. 
I tried putting the minimum clamp and adjusted the base idle table to above 500, but the car did the same when i startet it again.
So i took the idle valve out again, to see if it mooved when i turned the ignition, but i didnt. 
But when i look at the idle valve now that its out of the car it looks completely closed. I cant blow any air through the valve, so i dont understand why it revs high.

So i dont now if i should just block it off again and live with it like that or if its just me that dont understand how it works.

coldstart idle valve deblocked.llg

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6 hours ago, Reemen said:

So i took the idle valve out again, to see if it mooved when i turned the ignition, but i didnt. 

If the valve doesnt move when you turn ign on/off either the valve or the wiring is faulty.  So if you want proper idle control you will need to fix that.

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