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Discussion Starter · #1 ·
Hi everyone

i'm new to the site and in need of help on the way to work yesterday my car suddenly devolped a lumpy idle, i know coilpack is normally the issue but this happen 10 mins after i filled my tank up and it smells quite rich from the exhaust, also my diagnostic isn't bringing up any faults. could faulty petrol be the cause or could it be anything else

cheers
 

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well it does sound susicious that it was just after you put petrol in. Im surprised there are no faults. Could be coilpacks, they wont appear with fault codes. Or gunk in the intake manifold, injectors, fuel filter blocked. MAF. any of those issues really
 

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well........

Disconnect the MAF........and see does it run poorly. If it does, then the MAF is prob ok.

Might be an idea to put in some redex and blow some through to clean it out.

When was the last time the fuel filter was changed?

Coilpacks will prob show faults all the way up the rev range..esp at the top.....

Lastly the throttle body is an 1hr-2hr job....
 

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Discussion Starter · #10 ·
Right checked MAF and all was fine defo not coilpack or spark plug, added some redax to petrol so waiting for that to go throw hopefully if it is any blockage that should clean it out
 

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How do you know its not a coilpack? Id say the throttle body needs cleaning.
 

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Discussion Starter · #14 ·
I took each one of individually and the problem got worse on 1,2 and 4. on 3 it stayed the same so swapped coilpack 3 with one we knew was fine and 3 still had the problem, not the spark plug as changed that could poss be injector as when it was unconnected it had the same fault,
 

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Try and run some redex through just incase. if there was an injector i would of suspected a fault code. The throttle body clean would be my first port of call. Id retest for fault codes too.
 

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Hi and welcome![Y]

i have had lumpy idle problems in the past with no code showing on vagcom, turned out my prob was my MAF tho.....
 

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Discussion Starter · #17 ·
I've put some redex through with the petrol got advised not to put it anywhere else, so waiting to get low on pertol so i know its ran through so i can eliminate that. might give my MAF another look and clean that. re tested for fault codes and still nothing hoping its not the throttle body as looks a long job
 

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Yep just put a good amount in with your next fill/ top up. The throttle body will be well manky by now
 

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Discussion Starter · #19 ·
Well had 3/4 of a tank in when i put a bottle in so once the petrols ran out i'll re fill if its still the same throttle body will be checked.

someone at work has mentioned that it could be a a clyinder/piston that has gone wouldn't my engine be smoking if it had
 

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If the cylinder/piston is gone then it wouldnt run at all. Its something alot more simple and less harmful. Just not always the easiest to track down. Hopefully the redex will do it, and if not then a clean of the throttle.

Ps i bought redex in tescos yest, only the small container, for my mams car as it has the same symptoms. So put that in and took it for an italien tune. Ps it was half price in tescos - £1.60
 
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