plugging in to ecu

[Geo]

Quite where is the diagonstics plug for the ECU ?
I have a missfire and a lot of heat from the o/s exhaust, any suggestions please?

[nadirv8]

Mine is passenger side, about 1 ft up from the foot well- probably on the left where the wiring comes down from the dash... try there. Then its 4 screws to open the ECU box to gain access to the 9pin.

Also, I can't seen to get the diagnostics working using a 9pin-to-usb connector. If you get a 9pin input to the comp I think that would be better- could be wrong though.

Edited by nadirv8 on Tuesday 27th July 16:14

[Geo]

The software is to old...You need an old computer with a serial port on it...although these companies claim they work, they dont, i have came accross this prob many, many times before! Its all to do with the serial communication protocol.

[Tanguero]

Serial to USB converters work absolutely fine with the ECU software providing you have the virtual serial port set to be COM1 in Windows device manager.

[Gazzab]

Blocked Cat?
T-pot knackered?
Lambda sensor(s)?

[nadirv8]

Gazzab said:

Blocked Cat?
T-pot knackered?
Lambda sensor(s)?

perhaps a dum question but do the lambda sensors (the 2 sitting off the manifold) really make that much of a difference? Have the gearbox out at the mo and was tempted to replace them both.

Dave

[M3John]

Sorry to hijack the thread a bit guys but, would getting the lambers` round the wrong way make much of a difference to the way the car runs. Or is it not possible to get them round the wrong way?

[JensenA]

M3John said:

Sorry to hijack the thread a bit guys but, would getting the lambers` round the wrong way make much of a difference to the way the car runs. Or is it not possible to get them round the wrong way?

Yes it makes a big difference. The ECU takes readings from the 1357 bank and correlates them with the Lambda on the same bank, and vice versa. It's easy to connect them up the wrong way round. The wiring loom comes down the centre of the Gearbox then splits so you have 2 symmetrical connections for the Left and Right, and they will plug into either one.

[Geo]

Never thought of opening the ecu, lesson learned thanks! Earlier post was from a computer expert friend, knows little about cars, lots about computers so between us I would hope we get it sorted,

[Tanguero]

Geo said:

Never thought of opening the ecu, lesson learned thanks! Earlier post was from a computer expert friend, knows little about cars, lots about computers so between us I would hope we get it sorted,

Clearly doesn't know that much about computers either - serial to USB convertors work fine - you just need to understand that the MBE software is hard coded to talk to COM1...

[tvrgit]

Tanguero said:

Geo said:

Never thought of opening the ecu, lesson learned thanks! Earlier post was from a computer expert friend, knows little about cars, lots about computers so between us I would hope we get it sorted,

Clearly doesn't know that much about computers either - serial to USB convertors work fine - you just need to understand that the MBE software is hard coded to talk to COM1...

You're right, but it wasn't george's mate who was having difficulty with that, so no need to knock his expertise.

[Tanguero]

tvrgit said:

Tanguero said:

Geo said:

Never thought of opening the ecu, lesson learned thanks! Earlier post was from a computer expert friend, knows little about cars, lots about computers so between us I would hope we get it sorted,

Clearly doesn't know that much about computers either - serial to USB convertors work fine - you just need to understand that the MBE software is hard coded to talk to COM1...

You're right, but it wasn't george's mate who was having difficulty with that, so no need to knock his expertise.

I was commenting on

Geo said:

The software is to old...You need an old computer with a serial port on it...although these companies claim they work, they dont, i have came accross this prob many, many times before! Its all to do with the serial communication protocol.

Which (intending no offense to Geo or his mate) is frankly bks...and doesn't show much computer expertise. Well intentioned but incorrect technical advise can cause problems for people using it in future.

Edited by Tanguero on Wednesday 28th July 00:22

[fatjon]

I AM a computer expert and know my serial comms inside out. I can confirm that there are many different USB to serial converters on the market and I have tried quite a few of them on MBE, Emerald and several other ECUs. A very significant proportion of them give comms problems mainly due to problems with error trapping on the serial comms and slow handshaking due to inferior driver software. The older onboard 16C550 devices commonly found on PCs and laptops with a built in serial port are much more reliable. For the best chance of finding a USB to serial that works reliably look for one with an FTDI chipset and be sure to use the latest FTDI drivers. The Prolific ones are for the most part garbage and if it does not say it's an FTDI it won't be as they do tent to put it on the box in big letters to justify the extra couple of quid to those who know what they are looking for.

The MBE is, as was stated, hard coded to use COM1 so often you will need to go into device manager and make the USB to serial appear as COM1. This can be problematic if you have bluetooth devices/drivers installed or some phone connection software which has already grabbed COM1. the link below is a useful guide to how to change the com port your USB to serial is appearing on. Another problem I have seen is that the USB to serial devices appear on a high comport number (com11 upwards). Some software will allow you to select that port number (megasquirt) but it won't actually work.

All in all, if you can find some dodgy old ebay laptop with a serial port on it you may save yourself a lot of grief, especially if you connect to many different ECUs.



http://www.beaglesoft.com/232usb.htm

[Geo]

Fatjon,
I must admit that your answer is over my head but it seems to concurs with the info I was given, thank you