Idle code

rs2000 · Post by **rs2000** » Sun May 21, 2006 10:00 pm

I may have imagined this, but i thought i saw someone say they were writing a new type of idle code to allow a constant VE at idle.

It worked something like if TPS < setpoint and RPM < setpoint then VE = XXX.

Was it ever made, I can't find anything about it..

thanks
andrew

keithmac · Post by **keithmac** » Mon May 22, 2006 1:54 am

I did that, if coolant temp above threshold, map and rpm below threshold it goes into idleVE. It`s all linked into my custom code but if you just want that feature I`ll be able to tweak the firmware for you.

rs2000 · Post by **rs2000** » Mon May 22, 2006 3:53 am

Yeah that would be cool.. How hard would it be to implement?
I'm using 026h4 or h8, not sure.. is it just a matter of pasting in custom code or is there more to it?

andrew

scirturbo · Post by **scirturbo** » Mon May 22, 2006 8:59 am

Why don't you make all the ve bins around the idle point the same. Works for me...

SFC

----- Original Message -----
From: rs2000 (andrewr@iinet.net.au)
To: megasquirt-mss@msefi.com (megasquirt-mss@msefi.com)
Sent: Monday, May 22, 2006 12:53 PM
Subject: Idle code

Yeah that would be cool.. How hard would it be to implement?
I'm using 026h4 or h8, not sure.. is it just a matter of pasting in custom code or is there more to it?

andrew

This post is at: http://www.msefi.com/viewtopic.php?p=121478#121478

Posted by email.

keithmac · Post by **keithmac** » Mon May 22, 2006 9:11 am

You need to edit the .ASM file where the vecurr is calculated and either use that or substitute it for a VE value of choice. You also need to edit the .ini and create a menu for it to input all the variables.

With my code it waits until it`s in idle-mode before locking the VE but you could use a tps-threshold value instead, along with MAP, Coolant and RPM.

If you upgrade to 029Q it`d be easier for me as I`m all set up for that on the computer, still posible on the 026 though.

rs2000 · Post by **rs2000** » Mon May 22, 2006 8:57 pm

scirturbo I have tried that, and to an extent it works but not satisfactorily.

keithmac,

Yeah i can upgrade firmware if it makes life easier for you.. Basically all i use is 12x12 tables, ford IAC and RPM based AE, so any firmware that has these is fine.

Thanks again,

andrew

rs2000 · Post by **rs2000** » Tue May 23, 2006 6:33 am

Keithmac

I just did some searching and found you posted your version of the code here;
http://www.msefi.com/viewtopic.php?p=10 ... dle#109542

This appears to have everything i need, should i just try that one to save you having to do any work for me?

How does your code define 'idle mode'? Under what conditions does it lock the VE? Is it just under 1300 rpm, or is there more to it?

Thanks
andrew

keithmac · Post by **keithmac** » Tue May 23, 2006 12:45 pm

You can give it a go but I`m running a newer version, it would be interesting to see if you have any success with it.

Idle mode comes in after the car has fired the Idlevalve into action only with the tps below threshold, turns on idle timing control and idle VE lock, the idle valve control code is also different. The moment the throttle is pressed it comes out of VE lock and idle timing adjustment.

I`ve re-jigged the startup code since, and added idle specific O2 settings as well.

If you don`t have any joy with that one I`ll post my latest one up for you to have a try.

rs2000 · Post by **rs2000** » Tue May 23, 2006 6:01 pm

ok, thanks.

I had a bit of a try with it on the stim, i'll have a shot with it in the car soon..

andrew

Masi_K · Post by **Masi_K** » Tue May 23, 2006 11:54 pm

What happends when engine is cold ? Manual aux air control valve rises rpm from warm idle.

keithmac · Post by **keithmac** » Wed May 24, 2006 2:20 pm

Idle valve is given a cold starting DC, code runs from the turn of the key adding 300 rpm to idle target value for the start timer, idle then drops to target, igntion control active thoughout.

The code is reliant on TPS settings, if you do use it use Tools/ Review Mode in MT and check everything before you start it up. (especially the Idle menu).

rs2000 · Post by **rs2000** » Thu May 25, 2006 6:53 pm

Quick update. I loaded up the code and have had a bit of a test with a warm idle. It is very good so far, i was able to get it to idle richer than i was before, and this has made the idle much smoother..

I'll let you know how it goes in actual driving..

rs2000 · Post by **rs2000** » Thu May 25, 2006 8:09 pm

keithmac,

When is the idle VE not locked, as in how/what should i tune the bins that used to be idle bins for?

thanks again
andrew

rs2000 · Post by **rs2000** » Thu May 25, 2006 11:44 pm

Keithmac,

Been out driving quite a bit today and i have a great smooooth idle..

There is, however, a problem. When trying to pull from low rpm, the car bogs down. This happens pulling away from lights, in carparks, at roundabouts etc. The car just goes dead, and occasionally pops through the inlet. What i assume is happening is that it is stuck in 'idle mode' until 1300 or so rpm. My hot idle is about 950 leaves about 350 rpm dead.

What would be ideal is if the tps went over a threshold, say 7% (i idle at 5%) then it would switch off idle mode.. Is there anything like this in the code, and what other settings could i try changing to rectify this? At the moment i can put my foot flat to the floor and nothing will happen..

The idle itself is 99% perfect, so i'd like to sort out how to make it more drivable, i'v been doing 'boy racer' starts!! I'm using most of the default settings that came with the code..

thanks
andrew

keithmac · Post by **keithmac** » Fri May 26, 2006 12:55 am

This is the idleVE code,

" lda RPM
cmp #13T ;1300 rpm limit (failsafe)
bls IdleVE
mov tmp6,vecurr
rts

IdleVE: brset idleadvance,idlebits,IdleVE_YES
mov tmp6,vecurr ; Normal Table..
rts

IdleVE_YES:
lda idleVE_f
sta vecurr
rts "

It all hinges on the idleadvance bit which is set when the TPS is under threshold, it sounds like the code is not reacting with your tps properly or the threshold is too high?

Also the idle code will stay open until 2000 rpm with my settings, you can adjust the rpm where it closes in the first idle menu, I made the rpm delay because while holding the revs to set off in mine as the valve closed it dropped the engine revs which made seeting off tricky.

Do you see the VE in megatune change from the fixed ve to table ve as you press the throttle?

I`m runnning an idle switch rather than tps so this could alter thing slightly, if you have no joy with altering the TPS thresholds give me a message back.

I`ve got a later code runnning in 029Q, and one in the 029Q2-v5hi-res injector as well so I`ll post these up.

Just checked my later code and I`ve added a MAP threshold to idleVE lock so that should sort the flooring it from idle problem, but it should switch off anyway?

I`m on a stag do `till Sunday so I`ll post one up then

keithmac · Post by **keithmac** » Fri May 26, 2006 1:06 am

Just had another look, with TPS reading HIGHER than threshold the code goes into the closing routine which clears the idleadvance bit and unlocks the VE, deffinitely something to do with how the code is reading the TPS.

rs2000 · Post by **rs2000** » Fri May 26, 2006 1:53 am

I've tried tps ADC values of 0, 1, 35, 36, 40, 90.. at idle mine is 35. It seems to barely make a difference. The VE just sticks at the idle value.

At idle, when you press the throttle the accel enrichments lifts the revs to 1300 and it swiches and revs as expected. If you press the throttle slowly, it is possible to stall the car as the AE doesn't trigger, it lean out and stops.

Under load (for example 4th gear driving) i can floor it and the VE stays at my idle VE, doesn't switch back to the table.

So as you say it seems to be an issue with how my tps works with the code.. What can you suggest to try?

thanks
andrew

keithmac · Post by **keithmac** » Sun May 28, 2006 2:05 pm

I`ll have a look into it, tps threshold of 37 should be good enough, does it come out of the ignition timing table ok?

rs2000 · Post by **rs2000** » Sun May 28, 2006 6:12 pm

I'm running fuel only.. I'vw got a VB921 wired in, so i tried turning on the spark output to see if that would do anything, and it didn't..

Its a pity this is beating me as the code works really well..

keithmac · Post by **keithmac** » Mon May 29, 2006 4:21 am

rs2000 can you download it again and have another go, I`ve added a separate TPS check under the IdleVE menu (you`ll have to set the treshold there) if you have any joy let me know.

Are you drving the IdleValve from MS?

Cheers, Keith.