new oil pan gasket, check engine light came on, and no more fuel cut off...wth

[96-tsi-awd]

hey guys i have another 99 gst i just noticed started leakin oil from oil pan, so i took it to garage right nex to my work becuz i know the guy, and was just gasket needing replaced, well long story short. the gst is mainly stock other then evo3 16g turbo, stock injectors, walbro 255 fuel pump and wide band set up and have safc2 mounted but not set up....well before i took it there car ran perfect idled perfect and wideband was in range of 16.5-17.2 at idle and right in middle of lean and rich... but also wen drove it above 5k rpm had fuel cut off for sure...so i droped gst off this morning he fixed oil pan gasket and started to back out garage and i notice check engine light came on...and its running more to lean side but still at 16.5 at idle but nbow wen i get into it it doesnt have fuel cut off at all anymore...hooked obd to it n oxygen sensor came up, also he said had bunch of silicone around oil pan had to clean up... just tryna figure why check engine light just came on and why the fuel cut off suddenly went away???? any advice wuld be appreciated guys

 

[Abe'sGST]

As far as I know you having the oil pan gasket replaced and the code it's pulling shouldn't have anything to do with each other..did he by any chance disconnect the o2 sensor when replacing the gasket? disconnect your negative battery post for about 5 min. and see if the light comes on again

 

[96-tsi-awd]

ok ill try that, we actually cleared the code and it stayed off for about 5 to 10 min and wen i shut the car off it came on before, im thinkin he had to disconnect somethin cause never had no problem with my check engine light comin on before, but even witht that aside im runnin more lean now that he put neew gasket on and my fuel cut off isnt happening at 5k rpms anymore like it was, it like i have pro and con about it, pro is the gst runnin alot better and can actually get in it and con is check engine light is on now

 

[Black 95 TSI]

Do you know witch O2 sensor it is? You have do drop the down pipe to get the oil pan out. I have seen guys let the rear of the exhaust hang and break the downstream O2 wires.

 

[Abe'sGST]

yea, not getting fuel cut is good...What i would do if i was you is change the o2 sensor that's bad and maybe that will fix your lean problem as well. If your o2 sensor is bad, it can be sending wrong signal to the ECM, thus resulting in a lean condition.

 

[96-tsi-awd]

yeah he dropped the downpipe n said there was no gasket on it n silicon, weird, but actually the day after had oil pan gasket changed, i took n had safc2 hooked up and also swapped the 650 injectors in it n changed plugs, still wats good is no fuel cut off but now seem like fuel pump not gettin power at sumtimes, i have 255walbro, n idk ### is up with this check engine light but suddenly after had tuned and new injectors in and plugs check engine light went away , iv literally had over 12 2g eclipses/talons and non have really acted this weird about check engine light as this one...so now that have gotten all that squared away just have to figure out why sputer sumtimes with fuel pump its only wen have pedal half way down about 4000-4500 rpms and says its too rich on my wideband, but if i get into it pedal to the metal its goes just fine...maybe need to run direct power wire to fuel pump so no shortages????