Idle code

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rs2000
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Post by rs2000 »

The VEs I have come up wih are;

Temp, VE

20, 50
40, 40
60, 37
75, 34

Cold rpm 1100, warm 900

I may lean them off a bit, i previously had the hot VE as 31, but it seemed better at 34. Mind you things always seem different when you're not driving. The idle is quite sensitive, off by more than two points and it gets upset. The real test will be going for a drive.. i have a bad vibe that after having a rev and putting the clutch in the cars going to stall when cold.. it seemed to struggle a bit to get back to idle..

We’ll see!
keithmac
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Post by keithmac »

I haven`t had a cold stall for a while now, I`ve had probably 10 idle code revisions since the L code though.

See how it goes, you may need to increase the Dashpot.

Running ignition timing give you a lot more control over the idle speed/stability.

I rin a VE around 50 in the normal table, mine switches at 30c to an idleVE of 34, seems to work quite well.
Squirted VW GTI 16vG60 mk2
rs2000
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Post by rs2000 »

Well it does stall when cold. The idle is fine, but it stalls every time the revs drop from a few grand. I tried dashpot of 20 (up from 6) but it didn't appear to help. I don't really understand what a lot of the settings do, so i'm guessing a bit.. I have the defaults that came with the code in at the moment.

I took a datalog and the only thing i could come up with was that it might be getting too lean, so i turned of deaccel fuel cut, but the cars too warm now to test.

Would any of your newer idle code revisions help me do you think? I could just paste my block of locked VE code in.. If you do think they'd help, where are they available?

Once again i'm so near yet so far!!

thanks

andrew
rs2000
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Post by rs2000 »

This is showing up how little i understand how the idle code works..

Whats happening is while i'm driving around the idle valve is closing, meaning when i put the clutch in the car is instantly stalling, as the idle valve is closed. I need the idle vave to be open a bit to have any chance of the cold idle catching. This theory was proven by setting the 'Minimum (Freq)' to 30. No stalls, but once warmed my idle was too fast. I set the value back to 1.

I realised i have had 'idle valve closed (Freq)' set at 0. I tried setting it to 30 instead. I was only able to test it warm, but in this case the idle valve was closed to begin with, and stayed closed as i drove. Is it likely to do what i want when the car is cold? I'm hoping it will stop the valve from closing past 30 when its open over 30, but i'm not sure.. Anyway hopefully the car will cool down in a few hours and i'll try again!

andrew
evolotion
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Post by evolotion »

i had similar troubles with my valve its one of these open at 100, closed at 20(ish) and open a wee bit at 0 valves.

so closed has to be set to 20. only trouble is with jsut warmup only, you canst set a minimum DC :( so it has to go through this "closed" dc of 20(ish) so the engine stalls no matter what.
220ft/lb@7900rpm@20psi ..13.3@114 .. 1.4 16v rover k-series engined rusty mini.
keithmac
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Post by keithmac »

It sounds like the code isn`t reacting to the TPS, I`ll put a later code version up tonight and we`ll go from there if you like?

As the car idles you sould have a steady idleDC, when you rev the car and the revs drop below 1400 rpm the IdleDC should be increased by the Dashpot (ie if it idles at 30, when it drops to idle next tiem it`ll be 36 with the stock settings), this is the same as the stock idle code.

I think this is where the FuelVE problem came from as well, it should have locked in the normal code.

There`s 3 TPS settings, one in Idle Control menu, one in Advance at idle Menu and one in the IdleVE menu, make sure all these are 2 to 4 ADC higher than your TPS reading at idle.
Squirted VW GTI 16vG60 mk2
rs2000
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Post by rs2000 »

keith

Just had a look in the code and in the .ini There are a lot of different versions of tpsthresh, idlethresh, idletpsthresh, idlethresh_f etc. Some are defined in the ini but not in the code and vice versa. I have tried to work out whats what but am still not sure.. If you could post the newer version that would be great!! Then i can add my chunk of code and fingers crossed it will all work!

thanks
andrew

ps if its easier to email it to me my email is andrewr@iinet.net.au
keithmac
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Post by keithmac »

Right, I`ve found 2 lines of code that were pointing to the wrong threshold variable (a new set of eyes eh Andy :D), uploaded the code again so give it another go, the .ini hasn`t been touched.

This has been the problem from the start I think, that`s why the VE wasn`t being unlocked.

Have a try and see what you think.

Cheers, Keith.
Squirted VW GTI 16vG60 mk2
rs2000
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Post by rs2000 »

Yep thats done it!! I think a new set of eyes was what it needed, i was starting to loose it.. I had a play with it on the stim 1st and i understand how it works now, loaded up my bit of code and went for a drive.. It doesn't stall cold now and idles hot or cold. I'll have to see how it goes over the next few weeks and maybe tweak a few settings if needed..

thanks again, the idles sorted!

andrew
keithmac
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Post by keithmac »

Excelent! :D
Squirted VW GTI 16vG60 mk2
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