[thawkshaw]

I have a 2004 trailblazer with 4.2l and the AC goes in and out. I want to evacuate and recharge but can't find the low pressure port. I only see the one on the evaporator canister. Is that the correct one? If so my guage is way over into the danger area. I assume that might be the problem.

 

[c good]

There is no such thing as an "evaporator canister" on this AC system. On this vehicle, it is an "accumulator". The AC port on the accumulator is the Low Pressure (LP)connection to the system. The other access port is the High Side port and is located under the shroud on top of the radiator/condenser area in the left front of the engine compartment. HTH c good

 

[thawkshaw]

Thanks,
I assume then that the overcharge is contributing to the AC going in and out. Maybe freezing up.

 

[c good]

Is the Low Side Pressure high when the compressor is running? If so, it's overcharged if that's what you've been doing (adding more 134) Until you check both high and low side pressures while it's running (and compressor is engaged)you won't know for sure what the problem is. c good

 

[kodeblue71]

I also was going to ask this question. So, after eading this thread, I understand that I have to hook the refill canister up to the port on the accumulator? If so, how do I do this? My kit I bought has a threaded hose. The port appears to be similiar to a quick connect style.

 

[c good]

you must have bought the wrong kit (maybe for a Canadian System?) U.S.A. EPA laws mandate the quick connection type of fittings.

 

[kodeblue71]

I am from Canada lol.

 

[cowboyburns]

Where is the low pressure a/c port located on a 2002 GMC Envoy?

 

[c good]

On the accumulator. It's the aluminum looking cylinder right by the passenger side firewall. HTH c good

 

[julescole]

There is no such thing as an "evaporator canister" on this AC system. On this vehicle, it is an "accumulator". The AC port on the accumulator is the Low Pressure (LP)connection to the system. The other access port is the High Side port and is located under the shroud on top of the radiator/condenser area in the left front of the engine compartment. HTH c good

Thank you so very much...this is like the only place i've found the answer i was looking for. Who'd of thunk it would be so difficult to answer this question. THANKS AGAIN!!!!