Petrol engines 2.1 MV

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==Lambda probes==Bold text

Youde4: I've read many topics about the lambda probes and what not, and read that the engine wont run right without it plugged in (2.1 MV). However after some problems a few months back with running issues (lack of acceleration etc) I decided to unplug it and it ran much better without it. It's been disconnected for a few months now without any issues. (lambda was newish at the rime)

So, my question is why is it OKwhen everyone on here says it wont work without it? Surely an ecu this old wont have a safe mode? If anything theres a slight bit of hesitation with the first bit of revs but cant remember what it was like when all was running sweetly when i first bought it. It is rather gutless atm but i think that's due to the 205 80 16 MT's on it,


Syncrosimon: When you disconnect the lambda the ECU works like a DJ where the ecu uses look up tables to determine the fueling without the self correcting abilities of the lambda.

You will have a problem somewhere in the system and you need to trouble shoot the whole thing. Obvious faults indicate lambda shield wire grounding, spark plugs and wire faults, and coil faults.

California Dreamin I agree that they do run pretty well without but my understanding is the ECU will run in some sort of 'default' mode. I decated mine about 2 years ago but refitted the NGK branded sensor in the supplied boss.

Some suggestions here.
[1] and here [2]


Download a copy of the Pro Training Manual from here to work through the system.

Youde4: It turned out that the sensor was a universal one and did not work well, I put the original back in that was supposedly nakered and it ran smooth. No flat spot any more, but mpg and performance wise id say it was no different to when it was unplugged.

Simon Baxter: We have had lots of problems with universal type lambda sensors.
We use Beru, but Bosch are also good (if you discount that you can wrap the lead 3 times around the van!)