Check Engine Light On Please! Help.

[30 pak]

My 1996 Blazer Ck Eng Lt Has been comming on and off for some time When its on It cuts out misses and shifts exteamly hard from 1st to 2nd The next day the light goes out and it runs and shifts perfect. I got a code reader for christmas but like they say if it ain,t broke don,t fix it. well today the lights back on time to fix it. Came up with 5 codes po108-map sensor po122 Throttle position sensor po153 Bank 2 o2 sensor po442 Emission system leak small p1441 Auxillary emission controls I think I can Change out the TPS+O2 sensors They look easy as for the other 3 mainly emission system leak+Auxillary emission controls I have no idea what this could be also how hard is it to change a map sensor on a 4.3 Thanks for any input.

[Bronco2]

Clear your codes,run it and recheck. You may be reading history codes. Remember,codes tell you what system the problem is in,not what part to replace. The map and tps are on the same power supply-if the power going in fails it will set both codes because the ECM is not seeing a signal. Also, the usual repair procedure is to repair the lowest code first,the first code may cause additional codes. I would look very hard at wiring and grounds before you start replacing parts.

[30 pak]

Thanks for the advice Im allready into the beer tonight,I will clear codes tomorrow+run em again If you have time check me tomorrow+ ill let you know what codes the 2nd run turns out

[30 pak]

Bronco Thanks for the great advice you were right on.erased all codes= ran em again this time only turned up 1 code po122 Trottle position sensor. I"ll put one on and hope that fixes it, cuz its runnin like shit. I did unplug+plug back in the TPS didnt fix it. let you know how it turns out.

[Bronco2]

Cool-don't be surprised if some of the codes you cleared come back later. Evap systems are generally checked on a schedule, not every start. The o2 sensor code may need a few minutes at highway speed to set. Post again if I can be some help.

[30 pak]

Thanks again Bronco,How much do I owe ya.You definatly saved me some$ That one TPS fixed it I wonder How many People Run codes and replace everything without clearing codes first. Its beer time.

[Bronco2]

Anytime-unfortunetly,many people read codes and then "throw parts" at the car untill its fixed. As I said before, codes indicate the system problem, not the part to replace.As far as what you owe me,If I find myself near Kansas City, I might bum a couple beers out of that 30 pack. Later