Misfire help, what am I missing?
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Misfire help, what am I missing?
I have a 2003 TT Quattro with the 1.8. I am having a multi cylinder misfire condition, "16684 - P0300 Random/Multiple cylinder misfire detected " "16685 P0301 Misfire Cyl 1" which is throwing a check engine light. I pulled the codes in vag-com, and looked at the measuring blocks. It is showing a misfire on cylinder 1. I changed all 4 coil packs and it went away but soon came back. I pulled the plugs and changed them, and swapped the coil packs around. Still a misfire in CYL 1. I then even tried swapping out fuel injectors, to make sure it was a fuel issue. The light came back. I can reset it and it may not come back right away but within a day it comes back. Any help is appreciated
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Wanted to bump this and ask if anyone had any ideas? I replaced the connector plug on cylinder 1 today, to rule that out. I am at a loss as to what else it can be as I am only getting the codes for cyl 1 misfire. Could it be something like an O2 sensor getting ready to fail?
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you might have a stuck injector which could lead into engine damage due to too much fuel and not enough enough lubrication. I'm living this hell through my 2012 A6 2.0T... take your car to the dealer as they might have extended warranty on injectors
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He has already switch fuel injectors and still had the same issue and how would the vacuum leak only affect one cylinder? How is the engine running? Have you had any overheating issues recently?
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The Bally's can add to this, but in my hands on experience on my 2 A4's, a vacuum leak can uncover which cylinder is the "weakest" (maybe lowest compression, but still in spec for instance), hence the cylinder 1 misfire, but the key to me is he is getting the multi cylinder misfire code. You could be right, but I like to start with the simple stuff before I seriously dig into the engine.
I didn't do the work on my son's TT, but he had misfires that was fixed by replacing an elbow near the firewall and coolant reservoir by an indie in the Seattle area.
I didn't do the work on my son's TT, but he had misfires that was fixed by replacing an elbow near the firewall and coolant reservoir by an indie in the Seattle area.
Last edited by lyleswk; Nov 30, 2016 at 06:22 AM.
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So I did a compression check this morning. #1 was at like 45 psi. The the others were lower than what they should be as well. I am thinking either it is leaking between cylinders due to a faulty head gasket. Or maybe it needs valve work. Thing is it makes no mechanical noise, it runs and drives just that # 1 cylinder misfire. I am going to have my local shop look at it on Tuesday. He can do a leak down test and see if the coolant is showing any chemical signs of exhaust leakage.
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141,000 miles, timing belt was done at 89,000. Hoping it is something to do with the top end and not needing a complete rebuild. I will know better on Tuesday after I get a second opinion.