AC low side is blocked, Expansion Valve replacement required I'm told!

[lewisweller]

Today I took the Cayenne 06 TT with 4 zone climate control to a shop to replace the damaged AC service valves and vacuum then regas the system to spec 1050-1100grams with 10g pag oil. 

See image of new valves for low (right side)and high side (left side), as you can see they are vw parts and they pretty much fit any vw model and Porsche Cayenne and probably a whole load of other brands as the valves are generic for a lot of manufacturers and fit AC equipments which are standardise for obvious reasons. I went to Porsche and they didn't have any stock so went to vw and they had plenty. 

Move the power steering reservoir out the way for easier access. Second picture. 

The old low side valve (image 3) with manky looking chewed up Rubber valve which was stopping regassing according to the shop I tried 4 weeks ago after collecting from the garage who did the torque convertor seal job and left me with no AC working but before when I collected it (then had to return it due to massive vibration and a list of other crap), it did work which is strange but undercharged is all; (51oC when I collected it the second time with Jack all AC working thanks a bunch guys)! 

 

So getting to the issue.  .  ......

Vacuum was fine no leaks, re-gassed to 1100 perfect, started car and ran AC, nothing but hot air. Gauge for high side was perfect in the green zone, but low side was much to high above the green zone and in the red. The technician concluded the compressor was good but the low side is blocked. He said the expansion valve is likely blocked and thus the low side is high. 

Makes sense. 

So a few questions pls...

Q1. Is there any way a fault code or switch device/ sensor or valve located after the compressor could be off or shut and not allowing the refrigerant to not flow around to the condenser then onto the expansion valve and through the evaporator? 

Q2. How to get the expansion valve out, any diy pls,   I searched and found nothing. 

Q3. Is there any other possibilities to consider?

 

Appreciate responders. Thanks 

Edited July 13, 2017 by lewisweller

[Zakowsky]

Welcome back Lewis. In your other post you mentioned it was running fine – does that include the hesitation and stuttering (!), or did you, mean just the driveline issues? For the A/C I’d guess they bumped or bent the low side line getting the engine out since it happened in the shop, maybe straightened it so it is hard to see, but it might be worth tracing the whole thing looking for kinks.

[lewisweller]

On 2017-7-14 at 8:03 AM, Zakowsky said:

Welcome back Lewis. In your other post you mentioned it was running fine – does that include the hesitation and stuttering (!), or did you, mean just the driveline issues? For the A/C I’d guess they bumped or bent the low side line getting the engine out since it happened in the shop, maybe straightened it so it is hard to see, but it might be worth tracing the whole thing looking for kinks.

Hi Mike. 

Yep I meant the driveline is OK. The hesitation is still there and I'm considering if I will have the injectors cleaned or not. 

I ruled out a damaged low side pipe because when I first got the car back the AC worked but made a lot of noise under the dash evaporator/ expansion valve area and the AC would kick off as well then back on. I thought ok must be underfilled. 

The driveline was vibrating as well so I sent the car back to them. 

After a week I went to visit the garage and test drove it, AC felt better and vibration was gone, but air suspension fault wouldn't Clear and a knock was heard at the front strut area, so I asked them to recheck everything. After another week and the day before I went on vacation I picked up the car in a rush. The AC didn't work at all!!! I got pissed off and just left to get home asap, on the way it was 51oC inside the car I had to stop in a garage to try and get the AC looked at, they recovered just 175g from what should have been 1100g so I thought yeah it's undercharged and maybe leaking. Vacuum test was good, then he tried to regas the system but it wouldn't allow him, so he told me the low side is blocked or the AC service valve is damaged (which it was hence I replaced both yesterday). I drove home without AC and went on vacation for 3 weeks. 

 

Yesterday after AC service valve replacement, it re-gassed fine and high side was a good reading meaning compressor is on and working ok, low side was up in the 60's I think when ideal is between 25-40. 

I wonder if being open for a length of time in the dusty dirty gagrage the AC components got some dirt inside and it worked it's way to the evaporator/ expansion valve hence the noises I heard the first time I got the car back?  

 

Not sure what to do now, not looking forward to another garage disaster and bill. I read some people using high pressure solvent to access and blast out inaccessible system components and then vacuum the system out for like 1 hrs before regassing, in an attempt to avoid ripping apart the dash etc. 

Any advice? Anyone been through this?

Edited July 16, 2017 by lewisweller

[lewisweller]

Did some diagnostic using the vagcom vcds which was quite comprehensive in this hvac module. Only code was for low Gas, this was from before and resetting that code didn't magically Fix the issue unfortunately. No codes reappeared. 

As you can see the compressor is on and working, evaporator temp is basically the ambient temperature 39oC meaning it isn't getting a cold refrigerant through it at all. 

I went into advanced measuring blocks and done a full test. Everything worked perfectly flaps, blower, compressor etc. 

Flicked the economy button (which just turns the compressor off just like if you accelerate hard it kicks off to give max power) many times to try and kick the system into life but no luck. 

 

I've looked everywhere to find more info about replacing cleaning or serving the expansion valve and or evaporator but found nothing. 

There must be someone out there who has some tech info pls? 

 

[ekstroemtj]

Sorry Lewis that there is again some additional problem. 

Please explain. From your report i understand you changed the expansion valves right? But why the valves  in your pics are looking that different from what i found?

Edited July 14, 2017 by ekstroemtj

[ekstroemtj]

Semi professional search in our german forums. People complaining about a non working AC

 

not enough gas..... which you dont have

cracked or damaged pressure hoses.  Specially there must be some tubes close to the body of the car.

Problems with the seals / sealings

pronblems with the dryer 

problems with the valves. Instead of regulating the flow they closed.

 

sorry that i cant help

[lewisweller]

28 minutes ago, ekstroemtj said:

Sorry Lewis that there is again some additional problem. 

Please explain. From your report i understand you changed the expansion valves right? But why your valves are looking on your pics are looking that different from what i found?

Yes this is the expansion valve, which possibly is blocked on my car. 

But what I replaced was the AC service valves which are used to check and refill the gas only. 

[ekstroemtj]

Ok i got it. 

 

As i mentioned up there some reports here from non working valves which having the same effect like you describe.

 

the part is only 12 eur. Dont know how difficult to change

[lewisweller]

Further research points towards the RCV inside the compressor is faulty. 

 

Refrigerant_Control_Valves.pdf

[ekstroemtj]

Shure its a mechanical fault? There are several sensors and of course fuses

Involved.

 

[rik881]

@Lewisweller following this thread! 

[lewisweller]

I just took a gamble and bought a 50 dollar compressor control valve, I had some PayPal funds left from about 6 yrs ago I forgot about. 

 

It's listed as an original part (as opposed to the dirt cheap "non-original" 42 dollar part, thought I would lavish the old girl with 8 dollars extra wink lol) to fit compressor 7SEU17C which is the same as the 95812601400 denso unit fitted according to the receipt in 2011 when previous owner had Porsche in qatar put a new one in. Hope this works, even though they don't list Porsche Cayenne at all or VW Touareg! Fingers crossed this is going to be the ticket. 

 

 

Edited July 16, 2017 by lewisweller

[Brett968]

The pictures of the CCV you posted look very similar to the part that I found that fixed my problem. I believe there are only a couple of variants of the CCV for the 7SEU17C compressor that have pigtails, so it is likely that you ordered the correct part. As I mentioned in another thread, I can confirm that the Gogoal ECV03C is correct for our cars and it is readily available in North America. My car had very weak cooling. I replaced the expansion valve but this didn't fix the problem. With a new CCV the cooling has never been better. Even with temps in the mid-90s and a car full of people it has no problem maintaining 71 deg and in fact does so with only mid fan levels. Oh yeah, my car has 245k miles on it, original compressor.

 

Brett

[lewisweller]

8 hours ago, Brett968 said:

The pictures of the CCV you posted look very similar to the part that I found that fixed my problem. I believe there are only a couple of variants of the CCV for the 7SEU17C compressor that have pigtails, so it is likely that you ordered the correct part. As I mentioned in another thread, I can confirm that the Gogoal ECV03C is correct for our cars and it is readily available in North America. My car had very weak cooling. I replaced the expansion valve but this didn't fix the problem. With a new CCV the cooling has never been better. Even with temps in the mid-90s and a car full of people it has no problem maintaining 71 deg and in fact does so with only mid fan levels. Oh yeah, my car has 245k miles on it, original compressor.

 

Brett

Thanks Brett  your reply. 

As you mentioned in the other thread if the expansion valve was blocked then the rear would also need to be blocked as they both blow hot. This seemed to me unlikely or a really big coincidence, so I looked for a common fault which could only be something before the expansion valves which is the compressor, drier blocked, the condenser blocked or a crushed pipe. 

Now if the system was blocked the high side would likely pressure up way too high and its not really that high even with 45oC ambient temps. So like you I diagnosed/educated guess if you will, the CCV. This looks like no flow! 

Unfortunately I order the part but the Gogoal company aren't responding and there is no telephone numbers. I sent the few emails and also contacted them via paypal but no reply. I'm wondering if this order will be fulfilled. 

Today I'm going to drop into a parts shop which apparently has all car AC parts Spares and see if they got a CCV, time is the factor, I need to get this fixed and get the car sold. 

 

Thanks again Brett. 

[lewisweller]

So the local suppier didn't have the correct part. Lucky the next day I  the DHL tracking number for the one I ordered about 10 days ago, it arrived today. They also sent me email answers to my questions but after they shipped it, lol. 

The item I received looks very well made and heavy construction. I guess the 8 dollars more for the Original part instead of the copy part was worth it. 

Now I need to find time to get it fitted. .......

Edited July 22, 2017 by lewisweller

[lewisweller]

Good news the AC is fixed. Hooray. Fyi you don't need to remove the compressor to take out the valve, it would be easier but the time to remove and refit means I just worked around this with the guys in the garage to make space. Circlip pliers won't get in there so carefully using two long small flat blade screw drivers we massaged the clip out and reverse to install after. To allow the control valve to drop out (oring makes it sucked in there a bit, needs a good tug with pliers to release) then pull the rigid line in the way slightly over to allow valve to drop out downwards. 

 

The old compressor control valve was very warm to the touch and I think the solenoid was just totally jammed and thus it don't work mechanically. Inside was clean and no debris found. The old one has a plugged wiring harness where as the new one was hard wired. 

 

When that valve works you can hear the compressor kick In and hum under load, if that valve is stuck or not working it pretty quiet. That might help some others to diagnose their compressor control valve in the future.

Symptoms:

1. Generally Poor AC performance and sometimes could be intermittently on then suddenly off and not cooling. Or it just won't cool at all, blows hot or ambient air. 

2. Possible fault code for "open or short circuit in compressor". I didnt have a code but it could generate one if wiring was damaged or control valve melted or shorted internally. 

3. Low side Gas pressure higher than normal, high side either normal or lower than normal. 

4. When AC is running, press the "economy" button which will kick off the compressor (remember no clutch here so don't bother looking at the pulley Wheel unless it's sheared off because the compressor is seized up) if when you press the economy button off again and the compressor is not heard to come in and hum under load then likely the compressor control valve is faulty. Assuming the AC controller is working. 

5. If your front AC is working and the rear doesn't, or left side is good but right side is warm this is not a compressor fault. You need to look at flaps or the individual evaporator/ expansion valve for blockages but most likely the AC charge is low (750grams for 2 zone AC and 1100grams for 4 zone AC systems). 

6. Lastly with vagcom or duremetrics look to make sure the AC controller is requesting the compressor on and that current is showing like 0.8amp or something and a % of load is also shown. 

 

Bad news whilst the car was on the lift at the garage it dumped all the power steering fluid out both ends of the rack. The passenger side leaked clean fluid no problem its an easy fix and cost a few dollars with new seals but the driver side spewed out muddy looking rusty fluid and I'm pretty sure that side isn't easy to fix at all. Rack off jobbie I think. Anyone Fix the drivers side end seal? 

My luck has to change .............

Edited July 22, 2017 by lewisweller

[ekstroemtj]

CONGRATULATIONS!!!!! You deserve this victory after all this mess of the last weeks

[lewisweller]

Well the leaking steering rack is Fixed today. 

Top tip if you got the car up off the wheels don't steer the wheels, for some stupid reason the rack just pissed out the fluid both ends of the rack. First car I ever worked on that you can't move the steering manually at all if the engine is not running. 

All the fluid had leaked out and I was dreading another big Fix like rack removal and new seals or second hand replacement. 

Bought new seal for the passenger end which I Fixed before, whipped that out and found nothing wrong with it but fixed new one anyway. Reassembled and filled with 1 litres Pensotin CH11s. Leaving car on lift started engine and did lock to lock to bleed out air. Checked both ends and no leaks. 

Strange event! 

 

Some more bad news, the garage who did the convertor seal lost and then apparently found again my locking Wheel nut adaptor in fact put one that wasnt for my Wheel nut. So now I can't take the wheels off. And the passenger side bottom ball joint and tie rod end ball joint are both totally mangled. They weren't in bad shape prior to convertor seal! A** holes. 

 

Tie rod end is cheap enough but to buy the lower arm is expensive. And need to buy for normal Wheel bolts and throw away the locking ones as I don't have a adaptor now. 

 

Oh and just to put the nail in the coffin the front passenger strut air bag is leaking, it is actually visably chafed. After parking for just 5 mins its already dropped. 

Camera not popping out still. 

 

A long list and all have to be sorted before sale if I'm to get a decent price. 

 

On the bright side AC is lovely and cool. 

 

 

 

[Zakowsky]

Well good the the A/C is working, that's a major selling issue solved. If it is not affecting how it drives maybe if you just inform a new buyer of the ball joint being ripped up. Probably need to fix the air bag though. But it's sounding close to sellable; and don't forget it looks great, so when people idle around in the nice cool leather seats someone might overlook the few more repairs that are needed. As soon as they sort the lug nuts out maybe run an ad and see how the market is.

[lewisweller]

On 26/07/2017 at 0:55 AM, Zakowsky said:

Well good the the A/C is working, that's a major selling issue solved. If it is not affecting how it drives maybe if you just inform a new buyer of the ball joint being ripped up. Probably need to fix the air bag though. But it's sounding close to sellable; and don't forget it looks great, so when people idle around in the nice cool leather seats someone might overlook the few more repairs that are needed. As soon as they sort the lug nuts out maybe run an ad and see how the market is.

Here in uae they have a Mickey mouse car test which takes about 5 mins, unfortunately they will notice the boot of the ball joints on both items are split and will flag this as a fail. If the car was a cut and shut, crabbing down the road or total rotten through the chassis but with a nice bondo covering and rattle can spray attack, it would pass just fine lol. 

Priced up the lower arm, tie rod end and 4 new bolts 650dhs about 150 dollars. So looks like I'm spending again. ........

Edited August 2, 2017 by lewisweller

[lewisweller]

Lower arm and tie rod end replacement done. 

 

Ac is so cold it can cope with 44oC on speed 2 amazing! I'm so glad I spent a year suffering in the heat with this POS before finding the issue and fixing it. 

 

Now the AC is fixed and on low speed the check tail light and four wheel drive warnings don't even pop up on dash once you have driven it for a few mins and the battery is topped up after the cranking juice used, is replaced. 

 

So last job is to fix the rear camera which won't pop out. Oh and clean it again and Polish out the two new marks on the freshly painted door. Mo fo's here are so careless with opening their **** door on your car. Bunch of C**ts. 

 

Right that's my rant over for the day. 

[Zakowsky]

Sounds like you’re close to ending the saga though. Hope you come and visit occasionally once it is sold!

[lewisweller]

Just to close this AC issue out. Today was sitting stationary in a que waiting for vehicle test and it was 50oC, the AC was struggling but still I wasn't sweating so not so bad. The rear was warm air mostly so had just the front on which was cool just about enough. When driving the air flow helps and it's fine for this peak summer heat midday with full sun on a big front screen and dash. 

Conclusion is cayenne can't fully cope with 50oC but it tries it's best if in good working condition.