2nd nct emissions fail

bibi691

Hi am new here so not sure how this works exactly but sure here goes. I have a 07 vectra c 1.6 petrol, which has failed nct again on emissions. First test readings came back on high idle lambda 0.97, co 1.15, someone suggested throwing dipethanthate into it so i put about 500mls into nearly half a a tank and drove it hard for about half an hour tho as i learned today
that wasnt hard enough anyway took it down today this time lambda was0.98 and co 0.93, do i need to replace cat converter or should i try dipethane again only properly next time. Thanks in advance.

jimgoose

I'd start with checking the air filter and reading the OBD fault codes, if any.

greasepalm

try a bottle of cataclean as that works having made sure no faults stored.

https://www.youtube.com/watch?v=iuZm8-xTu0Y

bibi691

hi thx again for the reply should have mentioned my mechanic did a full service about 6 weeks ago which included an engine flush as the car does burn a little oil, he did say that there was a huge amount og gunk and carbon came out from the exhaust, could this have left some residue behind , he also feels that the cat is toast but this is just going by the nct readings and has not been checked, also had coils replaced about 4 months ago dont know if this makes a difference, also no faults stores and no cel

greasepalm

trouble is with dipthane it is not a fast cleaner and having it in fuel tank may bring up emissions reading,only 2 fuel cleaners we use are nova powerkleen and cataclean for instant quick results.