Hey guys. New to the forum and to grand prix's. I have a couple of issues that I would like some guidance on. Small backstory on the vehicle:
I recently purchased a 98 GTP 40th Daytona Addition (Pics to come). I needed something that was going to get me a little fuel mileage on top of being fun with potential for more. The guy selling it seemed to have taken pretty good care of the vehicle. There isn't any body rust, however the driver rocker may be starting. There isn't any misfires, however the transmission seems to be on its way out (I can limp it along for awhile yet).
After driving it through about 2 full tanks of gas it seems as if I am only averaging 12-14 MPG at best, which is horrible. I also noticed the temp gauge was only getting to about a quarter of the way up and the heat was not very warm. Beings that it didn't appear to be getting to operating temp, I figured that could affect fuel trims and mileage. So, I replaced the thermostat, which to my finding was gummed up and stuck wide open. But, after replacing it the heat came alive but the temp gauge was still in the same area, so I started leaning towards a temp sensor. Before I replace that though I would like to check coolant temps on a scan tool just to confirm whether or not the sensor is failing.
It also has a short ram cold air intake on it. But at any rate, I am completely baffled as to why I cannot get the mileage this care is capable of. Any help and direction would be greatly appreciated! ( I do drive the car nice AND I am not a gear head by any means, hence the advice seeking.)
