Failed MOT due the bad hydrocarbons! HELP :(

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Gibson
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Hi

Put my car into an MOT test yesterday after spend about a year doing it up i knew there would be problems with brakes exhaust etc (stuff i cant do) but the major problem was hydro carbons... The mechanic said its either the engine on the way out or filters.

Is there anything i could let him know that may help as the car hasnt been on the road for about 5 years but the last MOT never showed any signs of that etc!

If this helps i had an incident where the fuel tank fell off into a load of muck and stuff that may of gone in the tank after that incident it never ran right again could it be that? Also it smells very rich if that helps???

hope you can help
Many thanks
joe

prwales
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Re: Failed MOT due the bad hydrocarbons! HELP :(

what does it say on the print out, hydrocarbons is a strange one but it could be as simple as adjusting the air ratio on the k-jet, what do your plugs look like, sooty?

Gibson
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Re: Failed MOT due the bad hydrocarbons! HELP :(

hmm not a clue the mechanic said it was bad hydrocarbons (hes honest so we know hes not rooking us!) and as for the plugs they were replaced just before MOT and the old ones didnt look sooty or anything but wasnt paying much attention

I dont have the car back so i can't look :(

prwales
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Re: Failed MOT due the bad hydrocarbons! HELP :(

ok ask the mechanic to set up the k-jet with the gas analyser in your exhaust pipe, when did you last change your air filter, if you haven't then change it because a dirty or oily filter will affect the amount of air being mixed. If none of these apply and the mixture is correctly set up then it could be either valve stem oil seals or much more seriously, bore wear

Gibson
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Re: Failed MOT due the bad hydrocarbons! HELP :(

Hey!

I've asked the garage to do that he said no problem and he didnt seem to worried about it thinks you maybe right about the air filter etc :)

Fingers crossed Ill let you know!!!!

Thanks alot :D

Joe

j walker
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Re: Failed MOT due the bad hydrocarbons! HELP :(

I HAD A DIESEL ford granada which used to smoke a bit it had a trottle stop on the pedal ,i used to wind this out so there were no revs hardly ,and the contry garage where i went reluctantly agreeded that they should accept the car as presented and passed it accordanly , i think for such a low milage car like a g wagon tends to be ,you should cheat as much as possible with things like imission tests .people cause more pollution with barbques and those stupid patio heaters ,huaaaaar :!:

Gibson
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Re: Failed MOT due the bad hydrocarbons! HELP :(

Hey,

Well update it went in for another MOT and failed again!

Changed Air filters and tuned the car up cleaned sparks etc and did the mix aswell..Same again it failed on hydrocarbons!!!

Would a hole in the exhaust effect this or not? Also is there anything else that could be done? Would changing fuel filter help? the mechanic doesnt seem to be worried but any other advice and he listens lol
:P

Many thanks
Joe

fixwin38
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Re: Failed MOT due the bad hydrocarbons! HELP :(

K Jetronic is prone to running rich if not set up correctly or if the cold start regulator is not functioning... if tuned correctly engine should start from cold at 1000/1200rpm no smoke only steam ..run until coolant starts to warm and then the revs will drop to 700rpm ..no smoke.no steam...when starting hot engine revs go to 1000/1200rom for 5/10 seconds then 700rpm ..no smoke...a hole in the exhaust should fail the mot anyway..it could affect the back pressure and the egr valve....

prwales
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Re: Failed MOT due the bad hydrocarbons! HELP :(

what are the numbers on the emissions test?

peter perfect
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Re: Failed MOT due the bad hydrocarbons! HELP :(

Does it smoke? White smoke when on overrun, 280 are renouned for stem guide seals, but more improtantly has the car had a good run before arriving at the MOT station

Gibson
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Re: Failed MOT due the bad hydrocarbons! HELP :(

Hey!

Well it passed but the mechanic cheated on the MOT by removing the air filter and then putting it in for the MOT! As for the white smoke no it doesnt smoke at all and it hasn't had a good run for a while (which i dont know how many people told him to just bomb it down the dual carriage way!!!)

thaqnks alot for all your help!
Joe