Automotive Air Conditioning Information Forum

Hi,

2017 3.2L (P5AT) Ford Ranger, dual climate control

Only 45,000km (~24,000mi) and the AC goes warm sometimes. I can confirm this AC system has never been touched prior to the AC issue.

Took the car for a spin yesterday around 5pm (ambient temp 29C & about 90% humidity). AC was cool but then felt the drivers side vent momentarily go slightly warm & using infrared thermometer measured 18C but measured 11C at the passenger side vent. Figured it's a blend door issue. Kept on driving the car for another hour, passenger side vent temp got a low as 3C (for a long time) but the drivers side vent temp is always 6-7C warmer. As a quick & cheap fix I'm thinking I'll just pull & join the heater hoses to by-pass the heater core (did this on a single climate control Prado & the AC never went warm again).

Anyways, took the car for a spin again today @ around 6pm (ambient 29C & about high 96% humidity). AC vent temp (passenger vs. driver) 12C vs. 18C and it pretty much stayed that way for 10 minutes until the drivers side vent temp went to about 22C. Got home & put the gauges on while the engine was idling (engine @ operating temp). The gauge pressures were pretty high: 60psi (low) & 350psi (high). With engine idling the high side pressure went as high as 400psi so I turned the hose on the condenser & the high side pressure dropped to about 260psi, low side dropped to 50psi. Kept the hose running on the condenser for 5 minutes & the gauge pressures stayed pretty much the same @ 50 & 260.

One last spin @ 9pm (ambient 25C humidity 95%) and the AC is all good.

Condenser & fan issue?

To test the fan I put a thick piece of cardboard in the rotating fan blades for about ten seconds. Fan did not slow down too much.
Also left the engine for a couple of hours to cool down & then forcefully rotated the fan blades by hand. A lot of resistance - fan barely rotates, probably less than a quarter of one full rotation. Note that fan testing was done after cooling condenser down. When gauge was first connected & pressures were high, the airflow from the fan felt a little weak but it seemed to pick up a little afterwards. I've heard that there is TSB for the viscous fan clutch?

Temperature readings on the parallel flow condenser (low side 50C, high side 260C) inlet & outlet were a bit difficult to measure. It's an usual design plus the turbo hose is in the way of me getting the infrared thermometer close enough to get a good reading. Roughly 58C on the inlet & 34C on the outlet. Later on tonight (AC vent temps cold) I placed my hand on the condenser and noticed the top left corner of the condenser was not even warm (I could leave my hand there for hours). Moving my hand across it got warmer & it got very hot as I moved my hand down the condenser. If someone can have a look at then condenser photos (attachments) then perhaps you can tell me whether my 'feel' test result is normal for the design of the condenser.

Only other thing I noticed was there were a few bugs & grass on the radiator so I used the garden hose to clear these.

Hopefully it's a hot & sunny day tomorrow so I can see how the AC holds up with the extra heat.

Looking forward to the replies. Thanks.

(NOTE: The first photo is how you would see the condenser if you were standing in front of the vehicle)

Pressures are way too high, thus vent temps of between 53F and 64F. BTW for our USA readers your ambient is 84F
1. Please recall that an infrared temp gun is only accurate on dull black surfaces, so if you shot any aluminum your readings will be off. You can apply electrical tape to a shiny surface so that you can get a better reading. Would love to get accurate readings on condenser I/O. The readings you posted make no sense. (136F in and 93F out)
2. Is this new behavior? If so what was done to the car most recently before the AC started under performing
3. It is not clear from the condenser pix where the hoses or tubing connect. ie, where are the I/O connections located
4. We had a turbo car on here not that long ago and the owner had messed around with the physical setup of the turbo components. Took awhile to figure this out, now I ask for pix up front. Is there a turbo blanket? Please post several pix of your underhood arrangement, ie some engine compartment shots
5. Feel the pipe going into the accumulator. Is it cold?

Have to wonder why you get so many Rangers in for bad AC

This vehicle might very well have a re-heating problem, but the pressures are also much too high, as already mentioned, which is separate from re-heating. So multiple problems might be in play here.

The low side being in the 50 to 60 PSI range could be the result of a missing or damaged OT, or leakage around the OT o-rings, possibly due to deformation of the line that the OT sets in. Spraying water on the condenser doesn't bring down the high side into the normally expected range, either. This could be due to a partial blockage of the tiny passages inside the parallel-flow condenser or a compressor reed valve that isn't sealing properly.

If this vehicle is indeed a CCOT system, there won't be a receiver/dryer integral with the condenser as pictured. Is it a TXV system? If so, then the TXV might be stuck open.

A blockage in the accumulator due to loose desiccant beads obstructing the internal screen can also abnormally raise the pressures on a CCOT system.

It doesn't appear that the compressor has a control valve, so we can probably rule that out as a problem.

I've had a look at an aftermarket catalogue & also google searched the genuine part number for the AC compressor & yes there is no AC control valve for this model Ford Ranger.

It is also a TX valve system & there is no accumulator - the dryer filter is built in to the condenser.

I've attached some photos of the engine set up, turbo set up, heat exchanger set up & condenser I/O plumbing.

The turbo doesn't have a blanket on it but it does have a heat shield - same thing? It is also on the left hand side of the engine but the compressor & AC piping is all on the right hand side (when standing in front of the vehicle).

The heat exchangers are arranged in this order: intercooler up front, condenser in the middle, radiator at the back.

As for the condenser I/O pipes. I removed the turbo hose (intercooler-to-throttle body) & the I/O is a junction. Because the turbo hose was in the way, I took temp readings at pipes just outside the junction. I also did not put black tape on the aluminum pipes when I took the readings. If you look at the condenser photos you can see a thin pipe that starts near the bottom of the condenser. It looks like this pipe comes up to the junction and has two branches - one for the high side service port (yellow circle) & one which which goes to the TX valve (red circle). I measured outlet temp at the piping just before the service port maybe this why my readings are off.

I'm going to wait until the AC plays up again & then I'll try and get some accurate condenser I/O readings.

When you repeat pressures please have engine at 1500 RPM, windows down, ac max fan and max cool, and hopefully a digital thermometer in each vent in succession, as well as provide ambient. These are standard test conditions for an AC pro.
I need to study the pix more carefully they are a bit hard to view. Your shadow came out nicely, tho.
We would want the condenser I/O readings under those same conditions.

A heat shield is not the same as a turbo blanket, which wraps around the entire turbo body. Turbos raise the underhood temps considerably

Just re-read my second post and there is a mistake.

The yellow circled pipe is the condenser outlet which has the two branches.

The red circled pipe is the condenser inlet.

In the photo with the alternator, the turbo is behind & lower than the alternator. Can’t see it because it’s covered by a heat shield.

I’m going to by pass the heater core sometime today to address the temp difference between driver & passenger vents & then I’ll test drive it again in the late afternoon to see if it plays up again. I’ll do my best to get the readings you require.

Why are there 2 branches? Is this a dual air system?
Where do they go to?

tbirdtbird wrote: ↑Wed Nov 02, 2022 3:55 pm Why are there 2 branches? Is this a dual air system?
Where do they go to?

IMHO, I don't think so. I believe it has left and right dash controls for the driver and passenger, and possibly, the rear passengers if it's an extended cab truck.

tbirdtbird wrote: ↑Wed Nov 02, 2022 3:55 pm Why are there 2 branches? Is this a dual air system?
Where do they go to?

The branch going up goes to the high side service/gauge port
The branch going to the right (with HPCO switch/sensor) goes to the TX valve

Maybe it is just me, but I like visual clarity. Were it my car, I'd be using a can of brake cleaner on those 2 fittings and the pipes and the branches and get a better look at things. The greasy black gizmo to the left of the branch seems to interfere with tracing the pipes. Cannot see how the hi side pipe attaches to the block fitting