ECU address

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Telegram Sam
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ECU address

Post by Telegram Sam »

Mark @ Automark Stokesley, in whose hands I am, reckons that he ought to be one of the few people in the country that should know the address on my ECU for the idle speed setting - but he doesn't and is still searching. Does anyone (like Robsey ..) know what this is or where to find it? Sounds like it's a bit obscure.

Engine is SRi 2 L 20SEH 8-valve non cat Jan 91 (manual)
'91 H-reg SRi "130" manual hatch 8-valve non cat with mods
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Robsey
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Re: ECU address

Post by Robsey »

Telegram Sam wrote: Does anyone like Robsey ..
Not sure they do because I have no friends - lol.

Hmmm - I presume the address is more a matter of -
How do you change the idle speed setting in the ECU.

Is this with Tech 1 / Tech 2 / GlobalTIS or Opcom / Vauxcom or Vauxcheck?

If it is Tech 1 / Tech 2 or Global Tis or TIS2Web then PlanetC will be your man.

If it is Opcom / Vauxcom, then I would need to check this out on my Cav tomorrow before verifying if this is possible.

Vauxcheck - Don't think it can be done.

I am sure that it will probably be in the trim settings.
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Re: ECU address

Post by Cavalier342 »

Robsey wrote:
I am sure that it will probably be in the trim settings.
Now that sounds like you're talking about aircraft control procedures in aircraft without autopilot feature. :cool
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Re: ECU address

Post by Robsey »

Apologies - not aileron or flap trim settings.

ECU fuel trim settings.
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Cavalier342
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Re: ECU address

Post by Cavalier342 »

Far as I'm aware there is no flap or aileron trim, just elevator trim. Helps with ascending after take-off mainly but can be used in cruise also. :cool Flap settings usually have set angles. Aileron trim wouldn't be required, but is used on simulators.
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Robsey
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Re: ECU address

Post by Robsey »

Not really an aircraft or airframe expert...
I knew a lot more about that sort stuff as a thirteen year old.

More than thirty years of forgetting have passed since then.
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Cavalier342
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Re: ECU address

Post by Cavalier342 »

That's ok mate, there are hundreds of things that you are better in knowledge than I am! I just happen to like aircraft :thumb
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Telegram Sam
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Re: ECU address

Post by Telegram Sam »

Mark / Automark has done various sophisticated things (re-mapping) under the bonnet that are above my pay grade to follow and he has got an electronic box of tricks which talks to Cavalier 20 SEH's to do this. If to answer the query it is necessary to know the name of his "program" I can ask but it seemed that all he wants to know is where in the ECU the idle speed setting is concealed. Once known I think he can tweak it with what he's got.

Ailerons, flaps, spoilers and things will become more relevant once following the post-Searles rebuild the motor is fully run in ..
'91 H-reg SRi "130" manual hatch 8-valve non cat with mods
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Re: ECU address

Post by Envoy CDX »

Robsey wrote:
Telegram Sam wrote: Does anyone like Robsey ..
Not sure they do because I have no friends - lol.
Balls...
Check the Rules!

Raw 8v Power! - Bad Cav, Naughty Cav... Cav want's to do 90!

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Robsey
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Re: ECU address

Post by Robsey »

This is the Tech 2 description -
Apologies, but it is written in Vauxhall Geek Speak.

B-06 = ADDITIONAL FUNCTIONS
T01 = Tester Display Adjust Idle Speed Offset

In this mode, the idle speed may be modified and permanently stored in the
control unit within the range permitted by the General Type Approval (TA).
After each adjustment, communication with the diagnostic tester is interrupted while
the new idle speed value is programmed into the permanent control unit memory.

Since this is a time-consuming procedure, the scale of the modification
should be defined before the test is started.
The required value can be found in the corresponding Control Test "Idle Speed".

Ignition On
Engine Off
Accelerator Pedal Not Actuated
Selector Lever in position P/N
Press corresponding key in the system main menu to call up Additional Functions.
Select the desired test and confirm with [ENTER]
Follow instructions in diagnostic tester

Note:
If the following display appears after adjustment is completed, adjustment was successful.

The engine should then be started and the relevant datalist parameter (ENGINE SPEED)
should be observed.
The displayed idle speed must correspond to the adjusted value.

Selectable idle speeds = 680 to 1680 rpm.

Engine running at idle speed, operating temperature
All consumers turned off
Accelerator pedal not actuated

Nominal value = 570 to 730 rpm

(Haynes suggests that this should be 800 to 880 rpm.)

@ Gary - EnvoyCDX - Please note the "lol" at the end of my comment :P
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Telegram Sam
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Re: ECU address

Post by Telegram Sam »

Many thanks (it has always struck me that the Cav Forum is at its most productive in the wee small hours at the weekends, wonder why?). You will understand that I can do little other than copy and paste and send the Gobbly-de-Geek on its way. I'll let you know the response, if any.
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Robsey
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Re: ECU address

Post by Robsey »

I had to read this ( and 5 other pages just like it ) 3 times before it made any sense to me.

In simple terms - The idle speed adjustment is one of the functions found in the [ADDITIONAL FUNCTIONS]
section.

There is a common idle issue with the 20NE and C20NE engines where the car vibrates due to idling too slow.
Increasing the rpm eases this vibration.

Note that the rpm should not exceed 1300 rpm otherwise you will loose the "fuel cut off" function on over run.
( when Slowing down).
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Re: ECU address

Post by Telegram Sam »

I can actually understand that :)!
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Robsey
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Re: ECU address

Post by Robsey »

I never asked why he is looking to change the idle settings.

If it is due to vibration or slow idle speed,
it is good to check other items first.
Such as -
a dirty or sticking idle control valve.
a faulty air flow meter.
An air leak anywhere in the induction system.
Air intake trunking split,
Air leak between throttle body and intake manifold,
Air leak between intake manifold and cylinder head.
Split vacuum pipe.

I had an air leak between my throttle body and intake manifold when I first fitted my C20NE engine.
It ran really lumpy due to very low idle revs.
I fitted a piece of card board (document folder) cut to make a gasket - the revs increased to a better smoother level.
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Telegram Sam
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Re: ECU address

Post by Telegram Sam »

I'll pass these comments on also tks but I suspect that most / all will have been covered in the course of his engine re-build. The much more obvious explanation is the combination of a hi-lift cam and lightened flywheel, which I was aware of from the start.
Which leads to the thought: Is there a similar tweak that could be considered for compensating for the jerkiness when chugging along at 5 - 10 mph in the perma-queue on the Newcastle Western Bypass (= Mancunian Way?), or is this just an inevitable consequence of the mods?
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Robsey
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Re: ECU address

Post by Robsey »

Ahh - I see.

I believe that high lift cams can often add a pronounced lumpiness to the idle.
The fact that you have a lightened fly-wheel also means that there is no dampening effect to this lumpiness.

Life is full of compromises, and I'm sure that the loss of a smooth idle is the price you pay for the extra ooomph that you get from the engine modifications.
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Telegram Sam
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Re: ECU address

Post by Telegram Sam »

As you say ... When first I started out on this project I had no idea that this would be where I ended up
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Re: ECU address

Post by planetc »

I think, from memory that the idle speed was hard programmed on the seh. Software adjustment came with the ne. Although it has been many years and I may remember incorrectly. Jerkiness at low speed was always an issue with them, even without modifications.
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Re: ECU address

Post by Telegram Sam »

This does get a bit like black science to those not up to speed with car electronics but Mark at Automark seems to think that with his software he can change the idle speed electronically as opposed to mechanically, given the location of the setting on the ECU (which he told me is known to few apart from the Bosch man who designed the thing in the first place!). But Mark has not yet seen Robsey's helpful comments (unless the former works Sundays). I will report back but it may not be for 2 weeks.

[over the past 226 K miles I have been through phases where the jerkiness was irritating and others where it was quite livable with]
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Re: ECU address

Post by humbucker »

I adjusted the idle speed on Rage's Cavalier for him using my Tech 1a, although I can't recall whether he is running a 1.8 or a 2.0. It was pretty straightforward, but he probably has a different lump/ECU to the kit found in your car.
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Re: ECU address

Post by Telegram Sam »

Obvious query in the circs: Did you have to / were you able to find the "address" of the idle control in the ECU in order to do this, and if so how? I haven't yet been back to Mark since relaying Robsey's info to him but plan to do so in 1 week.

Is the setting of the idle control something quite different from what controls the smoothness or jerkiness when you are chugging along in a queue @ 10 - 15 mph, and can this be adjusted also?
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Re: ECU address

Post by Robsey »

There is no "address" as such.
Tech 2, Tech 1 and Opcom / Vauxcom use a procedure.

On the lines of...

Diagnostics >
1991>
Cavalier / Vectra-A>
Engine>
20SEH>
Programming>
Additional Functions>
Adjust Idle Speed Offset>
[Input offset value]
Program>


The only way you could do it via an "address" is if you were looking at the hex data tables in the Eeprom.
You would need to find the exact parameters within the hex tables that control the idle speed.
and adjust / modify the specific values to suit.
You may need to use an algorythm to "reveal" these parameter values.
:ugeek:
You would also require a PIC or Eeprom programmer and software.
All way out of my depth. :scratch
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Re: ECU address

Post by Cavalier342 »

Daft question, but can you not just find a suitable replacement ECU?
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Re: ECU address

Post by btcctroy »

Can you Map the engine with the software
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Re: ECU address

Post by humbucker »

Telegram Sam wrote:Obvious query in the circs: Did you have to / were you able to find the "address" of the idle control in the ECU in order to do this, and if so how? I haven't yet been back to Mark since relaying Robsey's info to him but plan to do so in 1 week.

Is the setting of the idle control something quite different from what controls the smoothness or jerkiness when you are chugging along in a queue @ 10 - 15 mph, and can this be adjusted also?
No, I simply plugged in the Tech 1 and changed the idle speed rpm under the 'adjust idle speed' option in the relevant menu (as Robsey describes above).
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