Aggie '91
08-22-2003, 07:43
Hello All,
First Off: I am sorry this is so long, but if your A/C does'nt work, you will probably willingly submit yourselves to this tortuous reading smile.gif
I am one of those that have a hot air A/C in my CC, so I volunteered my truck to "test" diff A/C fixes on.
There is another fix circulating around some of the dealerships here in Tx, (other that the current one that checks actuators & drops the R134 charge. I can't remember the TSB #, but it is mentioned on the forum)
The current "test" I am working with is to replace the current A/C orifice tube with a rear air orifice tube from a suburban (GM Orifice PN: 52477006). The R134 charge is to be 1.65 lbs.
I tried this on my system & at 1.65 lbs, it did not work as well as the TSB fix, however, at 1.5 lbs, the A/C was actually a little cooler than it was with the TSB applied.
Info so far:
All "testing" done with Temps in the 100 - 105 degF range & standard Texas summer time heat. 90% of data accumulated during rush hr drive time @ 5:00pm. (temps were 99 - 115 deg F by my mirror therm)
All a/c temps taken at the center vent on the dash. (my temp gage may be off, but at least the data is consistent).
Original A/C: Vent air at 73 - 82 deg
A/C with TSB fix: Vent air at 58 - 65 deg
With new test fix & 1.65 lbs R134: Vent air at 70 - 78 deg.
With new test fix & 1.50 lbs R134: Vent air at 53 - 62 deg.
The testing will be ongoing, I am going to run this for a week or so to verify things. We will probably be tweaking the 134 charge amount to see what effect that has.
According to the A/C guy I am working with, alot of people are seeing 10-25 degF DROPS in air temps at the vent smile.gif smile.gif smile.gif smile.gif
I know my data does'ent show this & maby my truck is stubborn, but if it will drop your A/C 10 deg, it is worth it!
I have been told that if the 134 charge is set very low, the system can have problems in the winter time (cooler temps equal a lack of gas expansion), that is why these guys are trying the 1.65 lb charge 1st, instead of the 1.55 lb. I think everyone is afraid that the systems won't work well in the winter with only 1.5 lbs. Time will tell . . . .
Rumor has it that there may be a service bulletin about this, but I don't know at this time. I just wanted to let everyone know that people are still working on this, and the the svc mgrs are VERY aware of the issues. This may not be for everyone, but for thoses that are intrested, the fix may become offical in the next 2-3 weeks, so keep in touch with your svc mgr.
Thanx
Aggie 91
First Off: I am sorry this is so long, but if your A/C does'nt work, you will probably willingly submit yourselves to this tortuous reading smile.gif
I am one of those that have a hot air A/C in my CC, so I volunteered my truck to "test" diff A/C fixes on.
There is another fix circulating around some of the dealerships here in Tx, (other that the current one that checks actuators & drops the R134 charge. I can't remember the TSB #, but it is mentioned on the forum)
The current "test" I am working with is to replace the current A/C orifice tube with a rear air orifice tube from a suburban (GM Orifice PN: 52477006). The R134 charge is to be 1.65 lbs.
I tried this on my system & at 1.65 lbs, it did not work as well as the TSB fix, however, at 1.5 lbs, the A/C was actually a little cooler than it was with the TSB applied.
Info so far:
All "testing" done with Temps in the 100 - 105 degF range & standard Texas summer time heat. 90% of data accumulated during rush hr drive time @ 5:00pm. (temps were 99 - 115 deg F by my mirror therm)
All a/c temps taken at the center vent on the dash. (my temp gage may be off, but at least the data is consistent).
Original A/C: Vent air at 73 - 82 deg
A/C with TSB fix: Vent air at 58 - 65 deg
With new test fix & 1.65 lbs R134: Vent air at 70 - 78 deg.
With new test fix & 1.50 lbs R134: Vent air at 53 - 62 deg.
The testing will be ongoing, I am going to run this for a week or so to verify things. We will probably be tweaking the 134 charge amount to see what effect that has.
According to the A/C guy I am working with, alot of people are seeing 10-25 degF DROPS in air temps at the vent smile.gif smile.gif smile.gif smile.gif
I know my data does'ent show this & maby my truck is stubborn, but if it will drop your A/C 10 deg, it is worth it!
I have been told that if the 134 charge is set very low, the system can have problems in the winter time (cooler temps equal a lack of gas expansion), that is why these guys are trying the 1.65 lb charge 1st, instead of the 1.55 lb. I think everyone is afraid that the systems won't work well in the winter with only 1.5 lbs. Time will tell . . . .
Rumor has it that there may be a service bulletin about this, but I don't know at this time. I just wanted to let everyone know that people are still working on this, and the the svc mgrs are VERY aware of the issues. This may not be for everyone, but for thoses that are intrested, the fix may become offical in the next 2-3 weeks, so keep in touch with your svc mgr.
Thanx
Aggie 91