I was wondering if anyone had any ideas on this. We have an old 2008 Infiniti G35x (the AWD model), it sat unused for two months, recently we started it up fine, drove it a bit, next day it started up and we noticed the A/C was outputting ambient temperature (wasn't cold even after waiting minutes). We turned it off, tried starting it again and wouldn't start. The battery was new, only about 3 months old, battery was down to about 11.7v so I put it on the charger, while I did my testing and narrowed the problem down to the alternator which was as old as the car. I replaced it myself (which was an absolute SOB of a job), the alternator was noisy when I spun the pulley by hand and it had "steps" I could feel, where it would lock up and then continue spinning.
The car is fine now voltage and starting wise, but I have a "new" problem, the A/C blows air just very slightly cooler than ambient. This was noticed before the alternator was replaced but I just assumed it was a side-effect of the bad alternator, or that it was my imagination. After a few days of testing it is indeed not putting out cool air.
A few years ago the A/C on this car also wouldn't cool, but for that issue I narrowed it down to the magnet behind the clutch because I could see and hear the clutch not engaging, I replaced it which fixed the problem. This time around the clutch is visibly and audibly engaging, so I'm at a loss as to why it would not be cooling.
Before I check pressures, my assumption was that if the system was low or high in pressure, the clutch wouldn't be commanded to engage at all since there's a pressure sensor wired into the circuit, if it does engage I'm wondering if that means the pressure is fine. I'm guessing there's also a possibility that maybe the system must have to be really low in order for the system to prevent engaging the clutch.
I also thought it might be some kind of IPDM re-learn issue, but I guess that's not possible because the clutch is engaging, it looks like all of the car's IPDM computer logic happens prior to engaging the clutch, meaning it checks the pressure sensor, ambient air temp sensor, all of that to determine whether to engage the clutch at all, so if it's engaging that means it must have passed all of its checks. IMO this pretty much narrows it down to low refrigerant or something else it can't account for immediately, like an obstruction or air flow over condensor or evaporator?
The car is fine now voltage and starting wise, but I have a "new" problem, the A/C blows air just very slightly cooler than ambient. This was noticed before the alternator was replaced but I just assumed it was a side-effect of the bad alternator, or that it was my imagination. After a few days of testing it is indeed not putting out cool air.
A few years ago the A/C on this car also wouldn't cool, but for that issue I narrowed it down to the magnet behind the clutch because I could see and hear the clutch not engaging, I replaced it which fixed the problem. This time around the clutch is visibly and audibly engaging, so I'm at a loss as to why it would not be cooling.
Before I check pressures, my assumption was that if the system was low or high in pressure, the clutch wouldn't be commanded to engage at all since there's a pressure sensor wired into the circuit, if it does engage I'm wondering if that means the pressure is fine. I'm guessing there's also a possibility that maybe the system must have to be really low in order for the system to prevent engaging the clutch.
I also thought it might be some kind of IPDM re-learn issue, but I guess that's not possible because the clutch is engaging, it looks like all of the car's IPDM computer logic happens prior to engaging the clutch, meaning it checks the pressure sensor, ambient air temp sensor, all of that to determine whether to engage the clutch at all, so if it's engaging that means it must have passed all of its checks. IMO this pretty much narrows it down to low refrigerant or something else it can't account for immediately, like an obstruction or air flow over condensor or evaporator?
