Fuel filter/code 1221
Tis afternoon I replaced the fuel filter on my 2002 GMC Envoy. Also changed rear shocks and washed engine with water sprayer.
When I went to drive it, the Service Engine light and Reduced Engine Power lights were on, and the Envoy only crawls and does seem to want to shift out of 1st gear.
Checked code and it shows 1221. Reset the hoses to the new fuel filter to make sure everything in place and they look good. Tried resetting code and it comes back.
Tried disconnecting battery for about 10 min and same result after reconnected. Currently trying disconnect for an hour or so to make sure everything is cleared.
Any ideas what might gave happened? Was running fine before the maintenance work today. Could the fuel filter change have caused an issue? Or the engine wash?
Thanks in advance for your help.