ecu m20 b25

[adam-325i]

iv bin told by a lad on here who does the upgrade chips to put my 2.5 chip in to my 2.0 ecu and my engine started fine and idled great but then i tried it once it cooled down and now it wont idle at all again but on the ecu loom there is 2 plugs that come off one is white and one is black if i disconnect the white one it will run and idle abit better i want to know what the plug goes 2 if any one knows

[Grrrmachine]

Slow down, use some full stops.

No 1, what age is your car?

No 2, is this a Speedtouch chip, and did you follow all the instructions (especially the 10-minute "learning" mode).

No 3, where are these black and white plugs? In the engine bay, or next to the ECU?

[adam-325i]

its a 1991 . was a 2.0 but now a 2.5
no its was a chipped before when i bought it but i dono how good it was in the first place .
and there next to the ecu mounted on the side

[Brianmoooore]

It's quite correct that similar aged ECU's for 2.0 and 2.5 M20 engines are identical except for the 'chip'.
The two sockets you refer to don't have anything plugged into them on most E30s. The only time I've ever seen them used are on cars with switchable auto gearboxes (rotary knob on the rear centre console) and/or aircon.
One of the aircon connections increases idle speed slightly when the aircon is on, buut apart from that, neither of these connectors have anything to do with engine control.

[adam-325i]

well before it was connected and it run fine and then it wouldnt. so i tried just unplugging it and it worked but it wouldnt idle till it had come out of the blue on the temp gauge. but im kinda of confused because i dont have aircon and my gearbox bwfore was just a standerd auto. what does the guru mean by its 10 min learning mode.

[Grrrmachine]

When you change the chip, it needs to "learn" the settings of the car. This means that when you've fitted the chip for the first time, you need to start the car and just let it idle for up to ten minutes. Then turn it off, turn it on again and take the car for a proper blat, using the whole rev range so that the new chip can see what all the sensors are reading under all engine conditions.

If you didn't do this, then no, the car won't idle properly.

http://www.e30zone.net/e30zonewiki/inde ... ting_Guide

Step 10

[adam-325i]

so how would i beable to like restart the learning mode cuz i had no idea of this when i did the chip swap

[fixedwheelnut]

Disconnect the battery for 10 mins and reconnect, start the car and let it idle for ten minutes should do it.

Most common fault if they won't relearn is the idle switch signal.