Ok so I bought the 2.0t coil conversion from 034 trying to get rid of a IDLE misfire I've had on 4, 5, and 6 on my stage 3 s4. Ive boost leak tested numerous times and found a few minor leaks that I've fixed. I've swapped in new ngk bkr7e's gapped to .028 per my old tuners recommendation. I swapped coils and 02s around, tried a diff maf sensor and new coolant temp sensor, and nothing changes. I haven't done anything with my egt sensors cause they were coded out. Sometimes itll throw bank 1 in the mix too but usually its just bank 2 that does it. I dont get a check engine light and it doesnt set a code or anything but u can feel the engine miss and daz raised my idle up to like 800rpm so not sure if misfires are there and its just not recognizing them. Before he raised my idle it was getting a misfire code just cant remember which cyls it was throwing the codes for.
I checked my mvb 91, 92, and 93 thinking maybe something was wrong with the base timing. 91 and 92 are at 0 and might go up to 1 here and there, but 093 says 7 for both sides. I know the spec is 4 and it seems that im over that ny a bit. Does that mean my cam to cam timing is off a tooth, or does it mean my cam chains stretched and tensioner pads need replaced? Could this be the cause of my misfire? Even if its not, how do I go about correcting this value? Just redo the timing belt, or do I need to do new cam chains and tensioner pads as well to get this value in spec? When I did the timing belt and cam plugs I used the cam lock bar and the crank lock pin, so not sure why its off so much.
Unplugging the n80 valve gets rid of the the majority of misfires with 1 or 2 on random cyls per cycle. When I plug it back in the misfires go crazy. So I'd say the n80 is leaking/not closing all the way allowing fumes in the intake, which is richening up my fuel trims. I took the valve off and hooked my mighty vac up to it.and it wont hold vacuum or pressure. Isnt this thing supposed to be shut when not activated? What tells the n80 to open and how much, the coolant temp sensor or vacuum? My boost gauge sits at 20 idling so everything seems to be where it should be. When I raise the rpm to like 1000 it goes to 21. Any help/advice on where to go from here is greatly appreciated as im beginning to go crazy. Thanks
I checked my mvb 91, 92, and 93 thinking maybe something was wrong with the base timing. 91 and 92 are at 0 and might go up to 1 here and there, but 093 says 7 for both sides. I know the spec is 4 and it seems that im over that ny a bit. Does that mean my cam to cam timing is off a tooth, or does it mean my cam chains stretched and tensioner pads need replaced? Could this be the cause of my misfire? Even if its not, how do I go about correcting this value? Just redo the timing belt, or do I need to do new cam chains and tensioner pads as well to get this value in spec? When I did the timing belt and cam plugs I used the cam lock bar and the crank lock pin, so not sure why its off so much.
Unplugging the n80 valve gets rid of the the majority of misfires with 1 or 2 on random cyls per cycle. When I plug it back in the misfires go crazy. So I'd say the n80 is leaking/not closing all the way allowing fumes in the intake, which is richening up my fuel trims. I took the valve off and hooked my mighty vac up to it.and it wont hold vacuum or pressure. Isnt this thing supposed to be shut when not activated? What tells the n80 to open and how much, the coolant temp sensor or vacuum? My boost gauge sits at 20 idling so everything seems to be where it should be. When I raise the rpm to like 1000 it goes to 21. Any help/advice on where to go from here is greatly appreciated as im beginning to go crazy. Thanks
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