As my Gti is standard I believe it has the Mems version 1.6 ecu fitted. this is a one plug ecu and the car has no alarm.
Was the Mems version 1.6 fitted to other rovers for the 1.6 or 1.8 liter engine still without the alarm so that I would not need to change the wiring if fitting a 1.6 or 1.8 litre engine?
does the Mems 1.9 ecu fit directly on the mems 1.6 wiring loom?

DotMatrix wrote: ↑Fri Apr 07, 2017 10:49 am As my Gti is standard I believe it has the Mems version 1.6 ecu fitted. this is a one plug ecu and the car has no alarm.
Was the Mems version 1.6 fitted to other rovers for the 1.6 or 1.8 liter engine still without the alarm so that I would not need to change the wiring if fitting a 1.6 or 1.8 litre engine?
does the Mems 1.9 ecu fit directly on the mems 1.6 wiring loom?

Mems 1.6 was never fitted to the 1.8 engine, although the ecu plug is the same as mems 1.9, the loom pinouts are different, so if you are fitting a 1.8 engine, you will need the mems 1.9 loom for it and ecu, (unless you are going mems3, then its mems3 ecu and loom). I've seen early 1800 metro conversions with 1400 mems 1.6 ecu with just the fuel pressure turned up to compensate!!. Also mems 1.6 ecus had early flywheels that wont work with mems1.9 as the alarm was just a starter immobiliser, which is easily by-passed, so the mems1.9 was done with the mnsr pattern to link with the ecu and alarm to kill the spark and injection. Easy indentification of a early flywheel is the ecu pattern on the back is a pressed in steel ring with missing teeth at 180deg, later flywheels have a machined ecu pattern for mems 1.9, mems2J, and mems3.

MEMS 1.6 was available with 5AS immobiliser just like later MEMS, at least in Germany. the problem was that it would have been easily bypassed with fitting an ECU without immo. that's why Rover had an other trigger pattern for this cars.

the funny, modular thing is, the general pinout is identical. so all main features uses the same pins from MEMS 1.3 to 1.9. there are changes like air con input, diagnostic pins (1.9 only uses 1, earlier uses 2 pins), MEMS 1.3 has the throttle pedal switch, later uses this input for other things.
injector outputs are always used at the same 4 pins, but not always all 4 are used. throttle body injection obviously uses only 1 pin, Metro GTi uses 4 but simultanious IIRC, MEMS 1.9 in general only 2 as it injects semi-sequentional so 1-4 and 2-3 are batched together.
side note: all PCBs are made for the small 18 pin connector, addressing the modular nature. sometimes used if wasted spark ignition is used.

nevertheless i would strongly recommend the correct loom as a wrong input by accident may damage the ECU

In the UK, generally the mems 1.6 had a 3as alarm which was the single button fob, although I did buy a R100 with spi that had a mems1.6 ecu and 5as alarm (2 button fob), the flywheel had a different pattern to the usual mems 1.6 and mems 1.9, so I sold the ecu/alarm and flywheel together.

thanks to you both for al the info.
so to sum this up. if fitting a larger k-series engine you need to convert the loom to mems 1.9 or 3 or something as the mems 1.6 was only for 1.4 litre engines. as the 1.6 litre k-series first came with the rover 400 of the mid 90'ies and that has mems 1.9 as standard.

i have run a 1.8 dizzy type engine on a metro gti ecu, i used the 1.8 injectors and kept everything else as per 1.4 it works and runs fine but may be slightly down on power