I didn't say it didn't cool. I said it wasn't as cold and I was asking if the readings are meant to jump around. My friend was checking if the compressor was going out.

I think it was the low side pressure gage that was going back and forth between the 30's and 70's. The high side didn't move that much i think it was somewhere in the 200's. We tested it on the econ mode and the low side was in the 70's.

He check for the vent problem that is in other A/C forums but it blows cold when you are on the gas pedal.

The main problem is that on short distances and slow speeds the A/C doesn't cool very well. The gas mileage I get out of the mariner is also way lower than the ford I have under the same circumstances. I have also noticed that at highway speeds the gas mileage is also lower than the ford. When going 30 mph the econ hardly ever kicks on when in the ford as soon as I get off the highway I can almost make it all the way home on the electric motor for about 5 miles.

In Houston I don't know where I could go to find someone I can trust to work on my hybrids. When I had my Ford's MECS pump replaced at the dealer it took 3 days the first time to get it replaced and it was done wrong so I took it back and took 3 more days to get it back. After that happened I really lost confidence in the dealer. I asked why this was and the dealer told me that they only had one tech that deals with hybrids and he doesn't work all the time. I guess he is a contractor for them and they only really worked on it 2 of the 6 days they had it.

When Randy in SoCal replaced the Mariner's MECS it took 15 min on the street no jack or frills. He just got under the front bumper took it off bolted the new one on and called it a day.

 

There are different ways but a system prevents the evaporator from freezing by disengaging the A/C clutch. Normally at this time the H/L pressure will start to equalize or low side goes up and the high side goes down. If you measured the pressure on a cold engine both sides would be the same and it reads the same if it's at full charge or way under charge. If your low on charge, your low side pressure will generally be lower and quicker to freeze the evaporator. Even at idle the clutch may cycle on/off frequently. At speeds, it can be worse.

It's possible that you have a bad pressure switch but that's just guessing unless you know that it has a full charge first.

 

Please let us know if you find the problem that is causing this. I am having a simular problem.

Like someone else posted, I don't have much confidence in the dealership technicians because there are very few hybrids around for them to work on, and generally don't seem interested in them.

I am thinking something is wrong with the compressor. Valves maybe.

Any input?