Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Phil-b on 17 March 2010, 14:25:54

Title: High Hydrocarbons
Post by: Phil-b on 17 March 2010, 14:25:54

Hi everybody I have year 2000 x reg facelift 2.5 with 98k miles. it gets regular oil & filter changes (every 4k) It has just passed it's MOT but I notice the HC reading has jumped from arround the 30 ppm mark of the last few fears to 188! so something is obviously wrong. I suspect the EGR valve may be restricted with mayo, is this likley or does any body have any other ideas. it does't burn/use any oil and seems to run well enough.

Cheers

Phil @ Scarborough

Title: Re: High Hydrocarbons
Post by: Kevin Wood on 17 March 2010, 14:38:05

How were the other readings? You can only really glean anything from a complete set, TBH.

Any sign of a misfire? HC is often associated with fuel that's burning incompletely due to a misfire or poor spark, assuming all the other readings are in order.

Be aware that the same car will test differently on different days due to weather conditions, fuel quality, etc. 188 is getting fairly close to the limit though (200 PPM IIRC).

Kevin

Title: Re: High Hydrocarbons
Post by: Marks DTM Calib on 17 March 2010, 14:43:16

Is it consuming oil and are the breathers nice and clean?

Title: Re: High Hydrocarbons
Post by: Phil-b on 17 March 2010, 16:25:02

Thanks for your responsees. No it isn't using any oil and there are no misfires. The other readings look ok, not sure what readings are relevent but lambda is 1.012 @ fast idle co is 0.083. @ natural idle co is 0.083 As for the breathers they have never been cleaned, and reading about this and the problems it causes it may be the problem. I get about 34mpg on a decent run if I dont flog it and it runs well enough.

Cheers

Phil-b

Title: Re: High Hydrocarbons
Post by: Welung666 on 17 March 2010, 21:47:24

Is the air filter clean?

You haven't got a K&N fitted?

Title: Re: High Hydrocarbons
Post by: Phil-b on 18 March 2010, 07:30:38

Hi Guys
Reply for welung666  No i dont have a K&N just standard air filter which is new.

Phil-b

Title: Re: High Hydrocarbons
Post by: Welung666 on 18 March 2010, 10:16:33

I only asked because the oil soaked K&N filters have a tendency to raise HC readings.

Title: Re: High Hydrocarbons
Post by: Phil-b on 20 March 2010, 10:11:03

Hi again guys. Regarding the high hc I have just remembered something. I filled up with petrol at Tesco and added some Redex not long before it went for test. I guess this could account for the high reading when nothing everthing else seem to be wrong. Senior moment I hope!

Cheeers

Phil-b