That will be the relay inside the ABS modulator block. Remove the top (one screw in the middle) and pull the relay out and clean the contacts. Also find the earth for thepump motor (it's a thick wire, you can't miss is) and clean the earth on the body and where it connects to the modulator block.

When reading fault codes, you need to retrieve all the codes that section is giving or you only get half the picture of what's happening.

So, the car totally died going round a slow corner a few days ago.

Pos clamp on the battery was sort of snug, but a couple of wires coming off it weren't.

So far, since tightening things up, no more ABS, no more crow.

Also noticed no battery clamp fitted.

I know - I KNOW - you mustn't ever expect a used car to be perfect, but seriously, a flappy around barely hooked up battery!?

Best guess, the battery/ wiring moving under braking, exacerbated by the warped brake disc making everything shake, was causing an electrical dropout that coupled to the box/ torque convertor basically going freewheel at lost speeds led to stalling.

Of course, the problem could come back, but 100 miles and counting without any signs of it.

Glad you've found the problem and fixed it! Yes, that will cause those sort of problems but it shouldn't have passed an MoT with an insecure battery. That said, because the battery sits in a well and can't really go anywhere they tend to overlook it on the 7/9xx cars, if in fact they can actually see the clamp is missing.

The big problem there was the loose terminal/leads from it though.

Has anyone asked what engine/car we are dealing with here?

Stalling problem - does it happen only after acceleration?

From memory from another thread, it's a B230F (FB?) but it doesn't matter now, it's fixed :



Just one little point here, might be misinterpeting what you're saying but there's normally no electrical connection to the lock-up clutch within the torque converter, mechanical only and only above 45mph if memory serves.

If the engine is turning, so is the torque converter (TC), if the TC is turning, so is the gearbox input shaft and the hydraulic pump within the gearbox. However at low speed, there's not enough speed on the output shaft to keep the momentum of the engine going. :nah:

It's why you should never tow an auto! Certainly can't tow/bump start them! :nah:



It could also be the battery clamp was removed after the MoT perhaps to keep a better battery than the one in the car which should be an 027 or if it's the heavy duty, 096 but you will need a normal lead-acid only battery, not a "Calcium/Silver-Calcium" type as they're unlikely to charge properly.

2L turbo 940.

And no problems on acceleration (other than it being tedious getting up to 30) or steady speed, it was only happening during braking/ low speed coasting.

Yeah, pretty much. The rest of the car can't act as a flywheel, at least when speeds are low. And this has only happened at low, ie sub 20mph, speeds.


Well, the MOT time wheels/ tyres were taken off for the PO's other 940, so I'm guessing there was some sort of battery faffaround too. Although the battery fitted seems healthy enough for now (of course, it'll only turn out to be a naff one dumped in come winter..). Which... I'd tell myself is fair enough, if they terminals had been done up properly and the smegging thing had a clamp stopping it rattling down there.

I mean "after" acceleration, say when stopping at the lights.

A specific problem is if the dump valve isn't working. The ECU won't read any airflow until the inlet depressurises, and that can take a few seconds (like 5 or 10s), during that time the engine will stall if you close the throttle and try to leave it with the normal idle mixture, which will be too weak to run.

If you keep the throttle pressed a little, or clutch in and rev it up a bit, you can keep it running while it depressurises with the open loop rich mixture. It is actually the closed loop lean idle mode that kills it (usually initiated by the closed throttle switch).

I experienced this recently after my dump valve control pipe had rotted out. I had also seen it before in a family members car, who had the turbo reconditioned, but the conditioner damaged the diaphragm.

Interesting.

So far, since nipping up the "But why are they even loose, dear gods was there anything good about this car when I bought it?" terminals, it's been fault free.

But if it does it again, I'll start poking around the turbo then. Thanks!

Actually, that's not quite correct. The BMC ADO16 1100/1300 that had the Automotive Products autobox could be towed without destroying the box; IIRC the innards were configured in some strange fashion that permitted this; possibly because the box sat in the sump and space was at a premium?