Lambda correction and lambda target map for MAP2?

[bofelix]

Hi to all,

I am running the S80 on a Subaru EJ25. Map1 is for gasoline and Map2 is for LPG.

Due to the fact having different injectors for gasoline and LPG the injection times differ.....

There is just one correction MAP. But if I clear the correction map and run on LPG (MAP2), then the correction figures for LPG are written in the correction map. Is there any chance to write these corrections to MAP2???

Is the lambda target map also used if engine is running on MAP2 (LPG)?? Or what is the ECU is doing if CL is switched on and MAP2 is active???

Best would be to have two correction maps and two lambda target maps.

Thanks for all answers!

Cheers
Stefan

[stevieturbo]

DTA has never allowed the corrections to apply to MAP2. It is rather annoying.

[Rob Stevens]

Are you using LPG now? I'm curious how you can make it switch to a 2nd set of injectors for Map 2, I've not come across that option.

[stevieturbo]

Are you using LPG now? I'm curious how you can make it switch to a 2nd set of injectors for Map 2, I've not come across that option.

You could use MAP2/ALS function so that when you turn MAP2 on, it operates a changeover relay switching 12v to the other set of injectors.

[bofelix]

Hello,

yes it has been done as Stevie described. The switch between the injectors is done with a relay inside the LPG control unit. The LPG control unit needs 55 secs to start circulation of LPG. The fuel pump is switched off after this time has elapsed. For this function a relay with 55 secs delay time is used (Bosch relay).
This works fine!!

I have seen today that Lambda correction table records also if the engine is running on MAP2. So obviously the DTA ECU does not separate on which MAP the engine is running.

Is the lambda target map also used for the engine if running on MAP2??
Is it correct that lambda recordings are done for MAP1 and MAP2 operation???

Thanks for all answers, cheers
Stefan

[stevieturbo]

The same lambda table applies to both maps. Corrections will be recorded, but you can only apply them automatically to MAP 1

I'm 99% sure the same applies to PC logging of lambda

If you wanted to use closed loop to correct MAP2, all I can suggest is you switch maps and run MAP1 as the LPG map for now until you have a good one created. Then you can revert back.

You would use the same lambda targets for both fuel, as the wideband doesnt know what fuel you are using.

[bofelix]

Hi Stevie,

thanks for your answer. It is a good idea to switch maps to get the correction applied to map 1.
I know that lambda sensor does not know the fuel, but I thought there are two lambda target maps. Then you could optimise the engine settings to both fuels. LPG ist less sentive to knocking, so it would be possible to run LPG on Lambdda 1 and use enrichment at higher speeds / loads just on gasoline.

But that would be the last 2% to get it PERFECT. Without it is still ok, because performance of the DTA ECU is great, even if you see the price....!

Cheers
Stefan

[Rob Stevens]

Ah, I was thinking that the ecu could switch to its pre wired 2nd batch of injectors when on Map2 , didn't think of using a relay.

[Jon K]

I asked for this as well. I run MAP1 93 octane and MAP2 93 octane + methanol. I drive in my methanol map mostly and so the corrections are only applied to MAP1 which I then need to apply to MAP2... annoying