My 1994 Blazer CPI will idle/run rough when it is cold, but as soon as it warms up, it runs great. OK, so I scanned it for codes (my SES light is always on because I deleted the EGR and installed a block off plate) and I got codes 22, 32, 34, and 38.

Code 22 - Throttle Position Sensor Error (signal low)
Code 32 - EGR failure (well its not there)
Code 34 - Manifold Absolute Pressure Sensor Circuit Signal Low (high vacuum)
Code 38 - TCC switch error

I have also noticed lately that my temp gauge is wacky. It will stay down low when cold, but as soon as it warms up, it fluctuates a lot. I mean about 150-210 while going down the highway. Does anyone think this could be a bad temp sensor? The TCC, TPS, and MAP could all be directly related to an error in the Temp Sensor. My next question would be that if it is the temp sensor, which one? There is one in the head and one by the thermostat in the intake. I think it will be the one by the thermostat because I think it is the one that reports to the computer.

BTW, I just replaced the FPR and nut kit and fuel pressure is a constant 55-56 PSI while running (cold or hot, does not matter). It also has a new radiator, 190 degree thermostat (used to run a constant 170-180 rolling down the highway), and had a complete coolant flush. There is no white smoke out the exhaust and it uses no oil or anitfreeze.

Any help would be appreciated! Thanks!