Hi im new to the forum and am having a huge problem with my 93 s10 2wd blazer. i recently removed the upper plenum to check the cpi unit for leaks as the the truck has 147000 miles on it and has never had one replaced. i didnt find anything wrong with the injector, regulator, or the fuel lines so i put everything back together and drove the car back to my parking spot. as soon is i got back to my drive way it started misfiring realy bad and was surging and stalling out at idle and would back fire if i gave it any gas. its strange cuz i drove it around and it drove fine. i did get codes off it when it started goin breserk, code 22, code 32, and code 34. i also checked for vacuum leaks and didnt find any so i disconected all the lines and put caps on them just to be sure and that didnt help. any assistanc would be greatly appriciated.

 

Code 22: Throttle position sensor voltage low, check to make sure none of your wires are loose other than that someone else will have to chime in with how to test it I've never had to tinker with one.

Code 32: EGR

Code 34: Vacuum sensor or MAP sensor

I'd start with double checking all wiring is plugged in nice and tight (check for corrosion on the plug terminals while your at it) since you said you had the upper plenum off as for the EGR pop it off and clean it (use a screened gasket upon reassembly)

 

well i spent all day messing with it and i seem to have it working again. all i did was remove everything attached to the throttle body and cleaned it and disconnected the battery. im hoping the troubles dont come back because other than being rusty its a nice truck. thanks for the help