Guys please help, I have an 88 iroc with a 5.7 on cold start the engine runs extremly poor like it is way lean. One guy said replace the maf but that did nothing so I borrowed a scan tool and on cold start at room temp the ect reads 115 degrees you start the engine it is lazy and stumbles but as it runs a few minutes it gets better. The ect within just a few minutes reading 245 degrees but the temp gauge hasn't moved and the engine does not seem hot yet at all. I replaced the ect sensor and it still works the same. There are 2 sensors beside each other under the throttle body, I replaced the one on the right without the metal clip. Maybe the ecm is bad? Also my tps only ranges from .52 v to 1.22 volts.

coolant temp sensor? I had a problem like that on a honda. It would think it was -30F all of a sudden and go into fast idle but never threw a code because it was still operating within it's range of possibility.

CTS (coolant temp sensor) is in the manifold on the passenger side of front intake under the Throttle Body..
There is also a manifold temp sensor (MAT) in most applications that measures the air temp in plenum, it is on the plenum at the drivers-side rear.
Either of these sends an inverse signal to temp to the ECM via decreasing resistance as it heats up.

Most are in this range:
Degrees F ...... Ohms
-40º ............. 100,700
32~38º ......... 9,500
68~72º ......... 3,700
158~162º ...... 450
194~198º ...... 250
100º ............. 1,800

So at the 115* reading you quoted it should be reading @1100~1200ohms when "Cold" vs. the 3500+ one would expect ...

If these check out then check the IAC function.

The guage in the car does not get it's signal from either of these sensors, it gets uses a seperate temp sensor thats on the drivers side head reight behind the first exhaust outlet port.