Any electronics/fuel injection ECU wizards out there?

Post by **pettaw** » 28 Apr 2005 05:28 pm

TPS, and IAT sensors aren't too bad, but the real stinger is the O2 sensor. Very expensive stuff. At over 100quid almost more expensive than the rest of the megasquirt installation.

And then I've got to find someone to butcher the downpipe so I can fit the sensor into it.

Post by **huskyracer** » 28 Apr 2005 06:38 pm

Universal 3 wire lambda probes are easily avalible from places like cafco, motor parts direct etc etc, and cost about 50 quid, or get down to the breakers and nick one out of just about anything, as they all work the same, chuck it in your tool box and pay the man at the yard for a switch blank nabbed out of the nearest car, not that I have ever pulled that trick LOL

Post by **jtbo** » 28 Apr 2005 07:55 pm

My lambda did cost 39euros, not so expensive

Post by **pettaw** » 28 Apr 2005 08:19 pm

huskyracer wrote:Universal 3 wire lambda probes are easily avalible from places like cafco, motor parts direct etc etc, and cost about 50 quid, or get down to the breakers and nick one out of just about anything, as they all work the same, chuck it in your tool box and pay the man at the yard for a switch blank nabbed out of the nearest car, not that I have ever pulled that trick LOL

Good plan. Know anybody to put the hole in the downpipe to fit it?

Post by **foggyjames** » 29 Apr 2005 12:49 am

Either take one from a scrapper, or buy a wideband if you fancy some crazy tune-it-yourself madness. Quite a few of the Turbobricks guys who are constantly changing things save a fortune in dyno time for remaps that way.

It doesn't really affect us too much though, as we dont tinker much, and Mr Huskyracer will work his PE magic for a bargain price!

cheers

James

Post by **pettaw** » 29 Apr 2005 09:49 am

Unfortunately the MS system can't work with a wideband, well it can, but you need a separate wideband controller, and I've already spent too much money.....

Post by **foggyjames** » 29 Apr 2005 10:15 am

You get me wrong...you use the narrowband for MS's own needs, then you hook the wideband up to a meter in the car for tuning. Well you can use it for both, but most people use a narrowband and a WB. I think they start at ~£250 for decentish ones with an in-car read out. If you're tinkering a lot, that's less than the cost of two remaps from scratch at some of the places we've asked about.

For what it's worth, I wouldn't personally get a wideband, but a load of people do. Mainly Americans

cheers

James

Post by **pettaw** » 29 Apr 2005 11:13 am

Ah OK, I get you, but the great thing about MS is that as I understand it you build your own maps/swap them with somebody else free on the internet and then simply upload to the EEPROM.

Post by **foggyjames** » 29 Apr 2005 11:18 am

That's very true, although it rather assumes that they have the same engine in the same condition, etc. If I were doing an MS installation, I'd most likely get it idling, then take it to a rolling road.

Jani, could you comment on your cold starting? I know a few guys running MS who have poor cold starting, although this is obviously a matter of adjustment as much as anything - it's about the hardest thing to adjust because of the limited time-frame!

cheers

James

Post by **jtbo** » 29 Apr 2005 02:32 pm

Yes, it is pain in arse to get that cold start to work properly and because I don't have auxialry air valve it is not easier.

For example this moring, outside temp around +4 celcius, I go into car, hook ms with laptop and check all variables, everything looks ok, I check that warmup enrichments looks ok, then I start, engine starts quite well, idling around 300rpm, when I touch throttle it dies -> too lean I think, I richen mixture by 5% and try it again -> still the same, another try, this time I pump throttle pedal gently and now I get it to around 1000 and there it runs pretty well, after 5 mins engine starts to be driveble.

Now biggest problem here seems to be that around idle warm engine needs quite small injector opening time, in VE table it is around 60% and with cold engine around 70 would be nice as near areas in VE map are around 70%. I must test this more, but it is difficult as engine get's too warm in 30-60 seconds, then it is in better area already.

Maybe I put that auxliary air valve someday, but now I can't invest to it and besides summer is coming, no problem then. Afternoons are around +10 Celcius and there is no problems either.

My temperature sensor maps are still too much off, engine is not yet warmed properly when sensors are showing fully warmed up. I need to find what is resistance of VDO sensor at 120 Celcius.

Post by **jtbo** » 29 Apr 2005 02:35 pm

Oh yes, Megasquirt can use data from Wideband O2 sensor, but it can't control it, so you need Wideband O2 sensor controller and sensor, then you hook it to Megasquirt and set Ego Switch Point to 2,5V and sensor type to Wideband. Works really well.

It could be that you need Extra code to use it, I'm not sure but there is no reason why not to use Extra code.

Post by **pettaw** » 01 May 2005 06:27 pm

Jani, the resistance of the CTS, is it the standard volvo one for the 360 injection? If it is, then you can use:

Post by **jtbo** » 01 May 2005 07:54 pm

It is from B200K, VDO sensor, perhaps same is used in Injection models too, that temp time switch was Bosch sensor and it has different resistances I think.

My sensor has around 836 Ohms at 25C temp.

Post by **pettaw** » 01 May 2005 08:05 pm

Right, you're using the temperature GAUGE sender to get resistance values.

Have you changed the reference resistor inside the MS box to a closer value?
Put the sender in 27c water and read the resistance and then use the closest resistor to that.

If its any help, then Mr Haynes says that the sender should be between 35-45 ohms resistance when the engine is at normal operating temperature.

Hope that helps.

Post by **jtbo** » 01 May 2005 08:57 pm

I don't need to change reistor in MS, all I need is to generate new map with MsTools2 and then compile code with these new maps and upload code to MS, very easy

Thanks from info about resistance, I think that now I will get it right, need to upload new code to MS before I go to work tomorrow morning, then perhaps it shows correctly.

I do use same model sensor for intake air temp too, works quite well