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got another 155, but have a big problem

my newly acuired 155 has failed her MOT spectacularly on her emissions this morning, readings are as follows

CO max 0.30% - actual 3.63% (run 1)
3.52% (run 2)
HC max 200ppm actual 211 ppm (run 1)
259 ppm (run 2)
Lambda 0.97-1.03 0.90

and on idle
co max 0.50% actual 5.10%

now, although i can take a car apart and rebuild it etc, other than replacing service items (just got a mate with a garage to order new plugs (8), oil filter, oil, air filter and lambda) other than the cat what else could it be thats making the results so god damn awful?

would appreciate your thoughts and inputs
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Re: got another 155, but have a big problem

i'd look at the coolant temp sensor, sounds like the car is running with the choke on...

also check the resistance over the lambda heater wires (the 2 white wires, should be a seperate plug from the grey-black wires), anything over 4 ohms and the lambda sensor is fubar...

you don't have any figures about O2 content in the exhaust, do you?
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Re: got another 155, but have a big problem

Aye! It could just be the lambada..

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Re: got another 155, but have a big problem

Any warning lights and is the car running well?

It'd be worth buying a tin of contact cleaner, opening every electronic connection you can see under the bonnet and giving them a spray. Lamda probe connector is the first I'd do - it is under a little plastic cover on the bulkhead behind the inlet manifold. Connector to temp sensor should be somewhere around the thermostat housing.

Normally, I'd expect a car with a problem in either area to run badly and the ems warning light to come on.
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Re: got another 155, but have a big problem

Had these sort of numbers when the lambda heater wasn't working on mine. Check heater fuse, relay, and all the wiring. You should have 12V on the heater connections with engine running. Also check and see if it's had an aftermarket type probe fitted with the joints buried under the car - they aren't often well made and can fail.
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