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Message: [QUOTE="Gnathv, post: 1545915, member: 29840"] [b]AC[/b] This is some good info from another forum. Weighing it in is very important and you’ve done that. R134 at 60 lbs pressure is 62 temperature. You need less pressure on low side. You weighed your charge so it should be right unless you have way more oil in system than needed. I would look at air flow across coils both condenser and evaporators. Leaking blend door can cause excessive heat load and raise pressures. I’d take a look at air flow through rear evap as you’ve replaced the front already. 1. The evaporator core(s) (you have two) are great collectors of debris. Air is moving through them with no filtration so over time they become clogged with decaying leaves, hair, dirt, you name it. This both restricts air flow and decreases the ability of the coil to absorb heat from the passing air. Clean them both. You will need to pick out the big stuff, then use a spray on coil cleaner to dissolve the muck and then flush them completely clean. 2. Your system has one compressor feeding two pathways. The front is an orifice tube system, the rear and expansion valve system. The rear system will self regulate, the front not so much. If you are really interested in getting this working, have the system evacuated and then change the dryer and orifice tube. There are a couple variable orifice tubes available. They work best when there is limited airflow over the condenser and low compressor speed - such as idling in Houston traffic. 3. Clean the cooling stack. Not just the condenser, which is the great bugcatcher up front, but also the transmission cooler, radiator, intercooler - all of them. If the radiator is full of cat hair and mud, the fan isn't pulling any air across the condenser. You really would only need to replace the condenser if the fins are all bent to hades or if its leaking. Its already a parallel flow high efficiency unit. 4. Check your heater bypass valve. Its supposed to close of the flow of coolant through the heater core when the a/c is in the max position. There are aftermarket valves that you can manually shut off coolant flow completely for the (normally) 11 months of the year we don't need the heater. Thank Al Gore for this winter.... 5. Proper charge. It really needs to be weighed in. Those of us who've been around since the inception of MVAC often times cheat and use gauge pressure and feeling the low side tube for temperature. Actually, on HVAC systems using temperature and gauge pressure to calculate superheat and subcooling are the only way to charge the big units because Freon quantity varies with the size of the tubing runs, but on a fixed system like yours, the engineers have calculated the optimum charge and you are unlikely to replicate it by gauge pressure alone ESPECIALLY since you have and orifice tube and an expansion valve drawing on the compressor output. Hope this helps. [/QUOTE]