C36 Misfire/rough idle advice please.

cazyp

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Oct 23, 2010
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266
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C43, Hilux
Just recently the C36 has developed a slight misfire - more noticable on idle than when driving. The rev needle fluctuates just a tiny amount - about 100 to 200 rpm.

It is worse on warm starting - although the car starts fine - it idles rougher when warm.

No fault codes showing.

I'm going to change the spark plugs but any ideas where to look then? Don't want to go down the route of random replacements of parts if I can help it.

Many thanks.

On a side note on the MOT - which it passed - it only just came down below the CO2 limit. Could this be related? o2 sensor?
Thanks
 

BlackC55

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Fault codes don't mean much in this case. The live data needs to be checked. Plug into a star and have a look at the smooth engine running menu. This will guide you to what cylinder could be missing.

Also check the maf and llambda values to make sure they are ok.
 

horgantrevor

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what millage has it on her

check fuel pressure at the fuel rail and clean the fuel rail filter

leave the star test running when you do this also check the oxygen sensor when the engine is running the reading should be moving up and down

i had this on my c36 turned out to be a faulty injector

if you have a spare maf swap and check

also i know the car can take three types of plugs as it says on the sticker under bonnet
but the bosch always worked best for me not the champion or breu

check ht leads for wear and also dont move the wire harness to much as could become brittle with age and you could cause more trouble

keep us posted
 
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cazyp

cazyp

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Joined
Oct 23, 2010
Messages
266
Car
C43, Hilux
I checked all the vacuum pipes - one was loose at the front - seems to have dome the trick!:thumb:
 

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