New to the forum so hi all. I've checked around online and found a few possible fixes but I figured I would come here and ask a question. I have an 86 full-size Jimmy, second owner. The original owner replaced the engine with a stroked 350 from a 78 Blazer (possibly 76). I am now getting a check engine light at odd times while it is running. I have plugged in a scanner and got code 23 which is either the MAT, TPS, or M/C Solenoid. Does anyone have any ideas where I should start? I'm just trying to save some time since it's my daily commuter. The only possible additional info I can think of is every so often the engine idle will slow down at stop lights for a brief moment. Thanks in advance.
