This is my first winter season with the 94 and I'm getting some rude surprises.

The warmup time is unbelieveably slow, much slower than any of my other cars. Is this normal for the 3.4? I had the thermostat out about a month ago to replace it and the parts goon gave me one with the wrong diameter. I put the old one back in and returned the wrong one for a replacement but haven't installed it yet. The bolt on the housing driver side is real nasty to get at!

And mileage!!! When outside temp droppped my around town mileage went right into the crapper. I'm lucky to squeeze 175 miles out of 15 gallons and that seems way too low.

The engine starts and runs fine, idles beautifully, etc. No check engine light or other issues.

I guess I'll put the scan tool on it and see what long term fuel trim values are.

Or is this stuff totally normal for a 3.4?

 

What temp rating is your current thermostat? For warming up the engine, a 160 is way too low to use in the winter, and 180 is marginal.

 

Thermostat is a 195F and looks fairly fresh but I will be replacing it soon with an AC Delco part. My experience with parts house bubble pack thermostats (e.g. Robert Shaw) has been very poor. Scan tool monitoring has shown that some brand new ones can't hold engine temp to specs as well as the 10+ year old one coming out!

 

My warmup time is around 10 mins and I have a 180 thermostat in my car.

 

I get warm air out of the heater in about 5 miles and HOT air in less than 10. You should have a 195° T-stat in the car and unless you have had your PCM programed for lower you could get some drivability issues. Also if your car is not heating up properly will kill your mileage and kill it fast.

Massey