My brothers escort gti failed an mot on emissions.
I know the cat is only a year old and suspected the lambda.
When i tested it it was giving very high readings (i expected this) but they was so high I thought maybe they was out of range and the ecu was ignoring them.
Got another lambda of a car and bodged the wiring up a bit but this hasnt helped the problem. After a good run this is also giving very high readings indicating that it hasnt helped lean out the mixture at all.

Any ideas on what to check next?
He changed the throttle body and the unit that bolts on the side of it. Not sure if that is the ISCV or throttle poistion sensor.

The MAF sensor is doing something as when unplugged the car runs very lumpy. I know this dosent mean its definately working right but just trying to save him a few quid before he sends it to a garage.

any thoughts would be good, and if there is a way of adjusting the mixture even if its just to get it through the MOT it would help and at least keep him on the road

 

Water temp sensor.

 

as you have been unplugging random sensors i would first get it out of limp home lol

 

I will try and borrow one from a mate who has the same engine and see if i get some better readings from that.

 

buy an odb scanner and stop guessing

 

whats the co level like first,,,,, any sign of a missfire or oil vapour in the burn can cause the mixture to go off,,,,, also if the cat was changed last year without sorting the problem ( the min for a mot is 200ppm but anything over 70ppm means theres a issue) even though the car would have scrapped past the MOT,,,, the following year the cats monolith will be fucked/melted ect,,,,, same counts if you used exhaust past when fitting a cat,,,,, that goes hard and spits pellets of it at the monolith and also kills the cat

get the emissions report and give me a bell in the morning as i used to do hundreds of warrantys on cars that had a cat replaced but the problem never fixed and i would recive the cats back chopped in 2 with the monoliths fucked due to fueling contamination,,,,, they get the emissions report after the new cat is fitted to find the ppm of 140 or sometimes higher...... the car still has a issue just that the government levels are VERY lenient !!

 

The results were

Eng oil temp gauge shown warm

1st fast idle test
co % vol limit 0.30 actual value 0.60 FAIL
HC ppm Vol limit 200 actual value 97 PASS
Lambda limit 0.95/1.09 actual value 1.08 PASS


2nd fast idle test
co % vol limit 0.30 actual value 0.56 FAIL
HC ppm vol limit 200 actual value 83 PASS
Lambda limit 0.95/1.09 actual value 1.07 PASS

Natural idle test
co % vol limit 50 actual value 0.99 FAIL

 

was it hot?

id say not