A/C Clutch keeps disengaging

[Guest]

Had my a/c compressor replaced and system converted recently. Did so because system would cool some then clutch would kick out. Had two places look at it and they showed me the front seal on comp was leaking and the clutch dropped because of leak. Well its doing the same thing with all new comp. System checks good when I take it in but when it feels like it the clutch drops and I sweat. Cycling on/off might work, some days are better than others but the problem comes back frequently...except when i take it back to repair shop. Also have a high speed miss intermittently and the problems may be related. Can computer cause this? Any ideas appreciated.

[GSMAG]

The clutch cycles on and off as a low pressure switch dictates. If the switch is bad, this will happen, but more likely, you are low on refrigerant.

[padgett]

Seems like the same topics keep coming up. See Chart 1 in 1C-14 "Climate Control Diagnosis" in the '88 FSM)<BR> <BR>Low pressure should be putting up a warning and setting B446, 447, and/or 448. You should see BI08 transitioning from HI (ok) to LO (low pressure) when the compressor shuts down.<P>After the car has sat for a while and with the engine off, check BD27 and 28. If system is charged both should read the same and above 40 (is calibrated in degrees but is really measuring pressure).<P>If so, your refrigerant is not low but the low pressure switch may be bad. The spec is for it to switch from HI (OK) to LO at 10psi (good system will be well above this when running). <P>What I would do to check in this case would be to pull the connector from the Low Pressure Switch and just jumper it. If the compressor stays on and you keep getting cold air, the switch is probably your problem.<p>[ 09-08-2001: Message edited by: padgett ]

[Guest]

Padgett..we live close-I'm in rockledge- but we speak totally different languages. I read your posts often and wonder if you realize that many of us have little idea what the h... your talking about with your computereze and your abreviations etc. My cars are 90's and have no crt etc. I have a manual-find it near useless.I have a set of microfiches with reader-its even less useful. I have read most posts on this site , have printed out many and find them far more useful. I'm sure yours are to some but for the most part it appears your trying to impress not help. Maybe I'm the only non-computer reatta owner but I doubt it. <BR>Saying the pressure switch is likely the problem is good. All the codes mean nothing to me. I have figured out some of your abbs but wish simple english was used, for us "dummies" <BR>My latest data..At 75 mph, the a/c on auto but not cooling the car will miss badly. I hit Off , the miss stops. Give it a few and turn on, if it starts cooling-no miss-if it still misse I know it's not going to cool.<BR>Sounds wierd I know but thats what I've found<BR>I.ll try the switch jumper and see if that helps. Thanks but thats the only thing you said that I understood.

[Guest]

Tried jumping the cable - no good Should I jumper the switch instead? That doesn't make sense.

[padgett]

If the problem is the same with the low pressure switch jumpered then the problem is not there - next most likely is the a/c relay itself. If the points are eroded they can heat up and increase resistance until the clutch drops out.<P>That miss sounds more like a wiring problem - bad/resistive ground is most likely. A/C clutch and fan are big electrical loads. Does the battery voltage indicator on the dash change or do the headlights dim when you turn the A/C on ?<P>However since the relay is easy/inexpensive, I would change that first.