I have a 1996 tahoe wth front air only ,the problem is my ac only cools down to around 63 to 65 out the vents.
Here is every thing i have done.
1. cleaned evap coil was very dirty –didnt help.
2. evacuated the system put under 28psi vacume for 24hrs—no leaks.
3. recharged with 40oz r134a and 3oz pag oil---no change in temp at vents.
4. blend door is ok..valve that controls heat to heater core off---no heat at core
5. pressure gage when ac is cycling low side 33 to 70. At 33 it cycles off at 70 it cycles on.
6. pressure gage when ac is cycling high side 70 to 100(varies) when cycling is off and 180 to 225 when it cycles on.
7. jumped the low side cutoff switch so compressor would stay running but only got down to 33 never went lower.
8. There is a cutoff switch at the high side output of compressor–unplugged it and system keeps working—didnt jump that connector.
9. measured temp with a Infra Red Thermometer at low side output hose on compressor its aluminum and looks like a (small inline acumilator) then goes into rubber hose that goes into accumilator on firewall (60 to 65)degrees.
Measured temp at firewall top pipe from accumilator going to evap and bottom pipe from evap (65 to 70)degrees on both..
Im not sure what is going on every thing looks fine except temps not cold enough.Is this all im going to get from this system.
On a side note hooked guages to my 1998 s10 4.3l and a 1997 ford ranger and they both cycle just like the tahoe but they go down to 20 on the low side guage before it cycles off and they cycle on very similar to the tahoe but the air at the vents is 52 to 55 degrees.
Could this be a low or high cutoff switch or a weak compressor.
Im up for any suggestions before i have my mechanic look at it....Thanks in advance for any help
---------- Post added at 09:21 PM ---------- Previous post was at 08:39 PM ----------
sorry wrong area mod please delete
---------- Post added at 09:22 PM ---------- Previous post was at 09:21 PM ----------
sorry wrong area mods please delete
Here is every thing i have done.
1. cleaned evap coil was very dirty –didnt help.
2. evacuated the system put under 28psi vacume for 24hrs—no leaks.
3. recharged with 40oz r134a and 3oz pag oil---no change in temp at vents.
4. blend door is ok..valve that controls heat to heater core off---no heat at core
5. pressure gage when ac is cycling low side 33 to 70. At 33 it cycles off at 70 it cycles on.
6. pressure gage when ac is cycling high side 70 to 100(varies) when cycling is off and 180 to 225 when it cycles on.
7. jumped the low side cutoff switch so compressor would stay running but only got down to 33 never went lower.
8. There is a cutoff switch at the high side output of compressor–unplugged it and system keeps working—didnt jump that connector.
9. measured temp with a Infra Red Thermometer at low side output hose on compressor its aluminum and looks like a (small inline acumilator) then goes into rubber hose that goes into accumilator on firewall (60 to 65)degrees.
Measured temp at firewall top pipe from accumilator going to evap and bottom pipe from evap (65 to 70)degrees on both..
Im not sure what is going on every thing looks fine except temps not cold enough.Is this all im going to get from this system.
On a side note hooked guages to my 1998 s10 4.3l and a 1997 ford ranger and they both cycle just like the tahoe but they go down to 20 on the low side guage before it cycles off and they cycle on very similar to the tahoe but the air at the vents is 52 to 55 degrees.
Could this be a low or high cutoff switch or a weak compressor.
Im up for any suggestions before i have my mechanic look at it....Thanks in advance for any help
---------- Post added at 09:21 PM ---------- Previous post was at 08:39 PM ----------
sorry wrong area mod please delete
---------- Post added at 09:22 PM ---------- Previous post was at 09:21 PM ----------
sorry wrong area mods please delete
