P38 emission readings off the scale - not fuel

Hi All, MOT failed on P38 due to emissions.

CO reading at 0.53 which is high but HC reading a whopping 1460!!! My local garage is great for MOTs but not equipped for a problem like this - any ideas?

What engine?

Martin1_01 said:

Hi All, MOT failed on P38 due to emissions.

CO reading at 0.53 which is high but HC reading a whopping 1460!!! My local garage is great for MOTs but not equipped for a problem like this - any ideas?

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When was the last time you really warmed up the cats. with long drive so they regenerate?
Could be bad sensor, cat. etc. best to get it on diagnostic.

tomcat59alan said:

What engine?

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A not very good one:lalala:

Hi 4.6 petrol. We have had it running for a good half hr and vehicle been stood in storage for couple of yrs. One thought was an air leak? Vehicle age is 1995 N but engine sound at 162k miles. Plugs and leads etc also done too plus fuel cleaner etc. But still can't seem to get the old girl back on the road

Diagnostic/lamda also fine

Fresh oil and fuel, needs a long warm up for cats to regenerate if they aint shot.What's the spark plugs looking like?

Also check the oil evaporator strainer in the hose top right rocker cover

For the CO -Air filter?, try spraying clutch/brake cleaner round the intake manifold, if the revs change you are drawing air in through a faulty gasket/split pipe which will account for the HC's

Misfire - The engine is passing fuel through that it hasn't burnt.Compression test,are you sure the plugs and leads are doing their job even though they are new? Coilpacks too.
Go round the exhaust ports with an infa red thermometer,a low reading on one port will tell you which cylinder isn't making progress.