Mega-Huge A/C Problem on 96 RR P38A

Ok, so where do I start... how about here:

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So to recap: Condenser Fans Innoperative A/C will blow very cold air, then warm up, cold air, warm air, etc. etc. Occasional squeal from 1500 - 2500 rpm's

I have had the system recharged, and it was 3/4 pounds low on R134A. Refrigerant, UV leak detector and PAG 100 oil was added. Now the cold air is very cold, but then goes back to very warm air.

I have jumpered the single pressure switch to allow the condensor fans to remain on the normal low speed and jumpered the dual pressure switch so the compressor will stay on.

I have replaced the clutch.

I am confident the squeal is my old and dry serpentine belt that will be replaced tomorrow.

New pressure switches will be here tomorrow or the next day (Rovers North is the best place for those, btw).

Here is what is happening: Air still goes from warm to cold, BUT I KNOW WHY: the clutch constantly engages and disengages. So I can rule out the dual pressure switch because it is out of the circuit completely, same to single pressure switch. I know for a fact it is not the clutch because a) there is a new one and b) I am losing voltage on pin 7 at connector C202 which is inside the pass. kick panel. That is why my clutch engages and disengages.

So why? My "service engine" light is on, but it came on at 82k-ish miles, and I have 85k on it...that should be normal, right? All the light does is tell you its time to give your dealer some money at 50k and 82k...or is it?

I now have 2 theories:

1) there is a componet that is loading the engine down so it tells the BeCM which tells the HeVAC that it doesnt have enough power to run the A/C and turns it off 2) my HeVAC is screwing up

I have not checked my A/C charge so there is a chance it could be low, but that would be determined by the dual pressure switch that is out of the circuit.

I did note that I was getting 12.5 (+/- .5 volts) at the clutch and I was getting 13.2 volts at the connector in my pass. kick panel.

I have service manuals and the ETM (RAVE CD actually) but I can not figure out where to troubleshoot next.

Surely somebody out there can help me!

Dave snipped-for-privacy@mac.com

Reply to
David Blasingame
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I Have a 95 RR 2.5DT. I've been running thru problems with the AC, too. Try and check the 'In Car' temperature sensor. That would be the cheapest way. Then, maybe the electric motors that are regulating the ventilation broke down. It's a bit more expensive, since you have to take the dashboard out. Or, the ECU can go bananas. Even more expensive. HTH.

-- Henry! Q. Why do some bands even have bass players? A. To translate for the drummer.

"David Blasingame" a écrit dans le message de news: snipped-for-privacy@posting.google.com...

Reply to
Henry!

Hi Dave I had a similar symptom and it was caused by a sticking pressure regulator valve. This is a mechanical valve that regulates/controls the pressure in the low and high pressure sides of the system through the evaporator. It is bolted on the engine side of the bulkhead and the AC pipes go through the valve into the cabin. Both pipes go through the valve. It is not too difficult to replace and the part is used on other makes, some BMW's use the same valve. As far as I am aware there is no way to check it other than swapping a suspect with a new one. It is normal for the clutch to constantly engage/disengage, even in hot weather. Hope this helps

Gary

1989 Classic 1998 P38
Reply to
Gazza

Thanks for everyone's input.

I have heard suggestions of a expansion valve, pressure regulator, blend motors, and in car temp. sensors. All of these have crossed my mind, I just need a way to test them.

Do any of these have a feedback to the HeVAC that would constantly turn my compresser on and off?

Dave

Reply to
David Blasingame

The compressor is always turning on and off. I asked this to the Rover motorist, and he told me it was OK. I had the silent blocks changed, and heared nothing more. But the motorist could have told me that the fairy godmother of the valvotron was ill, I have no clue...

-- Henry! Q. Why do some bands even have bass players? A. To translate for the drummer.

"David Blasingame" a écrit dans le message de news: snipped-for-privacy@posting.google.com...

Reply to
Henry!

Are you in UK? Near Oxford? Take it to James French in Standlake, they will sort it out and save you a lot of hassle...

:)

Reply to
David French

I am in Arkansas, USA.

The closest dealer is 80 miles away, and they have a horrid reputation. I know of one British car mechanic. He deals mainly in Roles Royce, Lotus, etc. and is actually ordering the test equipment to get started on Rovers, but that could be a while.

Dave

Reply to
David Blasingame

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