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I’ve been chasing a slight miss on idle on my 2008 1.8 tfsi. It’s had new maf, plugs, vac leak check etc. So this morning I changed the injectors. The old ones that came out were fairly messed up. It’s driving absolutely fine, more responsive, smoother etc. However it’s a bit lumpy at idle. Quite a bit more than it was before. I’ve checked for fuel leaks and it all seems good. I’ve only driven it 5-6 miles. Am I just waiting for trims etc to adjust to the new injectors? Long term fuel trim was sat around +6%.Or is it manifold off job again?
 

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Discussion Starter #2
Ok, so just updating this a bit after a bit more tinkering. Looking at live data with obd eleven Turns out there’s a misfire on cylinder 3 after changing the injectors. Swapped the offending one back to one of the old injectors and it’s still there. Only at idle though.
 

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I’ve tried plugs, coil packs etc. It was right after I installed the injectors that it happened.
Are you sure you didn't have the misfire before with the old injectors? Did u check it with ur scanner before when u had the old ones? Sometimes old injectors can mask the misfire and you won't notice it, so after you install a new healthy injectors that releases more power, that's when you'll notice it. If it's a soft misfire (no cel) I wouldn't worry about it. It's common. I have a misfire, my buddy has a misfire, but no check engine light. Only shows with a deep scan from obdeleven or vagcom.

What I can suggest to you though if it really bothers you. Do a walnut she'll carbon cleaning.
Then buy yourself three different sets and brands of spark plugs (you'll thank me for this) because you'll really be able to tell which runs best and which one smooths out your misfire,
Get a set of bosch, get a set of ngk, get a set of densos. Run them and test drive them and listen to the idle sound see which one you find best. Trust me the plugs make a big difference, even though you said it came out after the injectors.

From my experience, I've tried ngk iridiums and my car ran like shit. I've tried densos and my car ran ok. Then I tried bosch double platinum and my car all of a sudden ran great. Try bosch double platinum and see if that gets rid of your misfire.
 
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