First, I’ll watch this a few days before panicking! While testing my AC output in low mode (more below) I had the engine between about 2500-3500 RPM in park. Outside temp was pushing 100F, battery was low from not driving it much. Suddenly I got the restricted performance light (rpm @3500) and it stumbled a bit. First time ever. I immediately shut it down. I later restarted it and there was no light, I let it idle maybe 15 seconds, then shut it down. Next step after some research was to do a hard reset of the battery (offline about 20 minutes with several touches of negative to positive lead.) Then I hooked up my battery tender and let it charge a while. A thunderstorm cut short the charging as my parking space is outside my townhouse. I am hoping the RP message was an aberration, but I may stop by one of these auto stores and ask them to scan it and tell me if I have a code/codes that might suggest a coil problem. Car is a ‘2003 VDP, mileage ~53,000.

Re the AC, I thought the output was weak in the past few weeks. We have a heat dome at the moment so I dropped it at my Indy general purpose garage to check the pressures in case an O-ring had let some Freon leak. Nope: at abut 90F low side was 40, high side 200-235. Home it came after I apologized for “old fart paranoia” and then remembered I’d read somewhere these AC units really don’t perform well in high ambient temps.(My Prius will put icicles on the vents in short order.) I tested the temperature drop from outside to what the vents put out with the system set to low. Outside ~98F, vents got down to just under 72, even with dummy me leaving the door cracked which inadvertantly made the recirc mode pull in warmer air. Question: is this about normal AC performance?

Thanks, and I’ll post back in a few days to update or hopefully close out the restricted performance issue.

 

The high side 200-235 is a bit high. I know you have a lower mileage car but, if there’s a bunch of bugs in the condenser, that’ll certainly make the pressure higher. Is the lower skid plate under the front bumper there? I imagine so but, I thought I’d ask.

 

Yes, all the protective stuff behind/below the bumper and under the engine is still in place despite my best efforts to scrape it off at parking spot concrete barriers and curbs! I tried to get a look at the condenser yesterday but it was so darned bright (and hot) at midday that even with a strong flashlight it was hard to see stuff buried in shadow. I'll take another stab at that today. My primary focus for the moment is to be sure the RP issue is not going to rear its ugly head again or interfere with annual mechanical inspection in August! I don't think I have to have an emissions check until next year.

 

Once you get to the parts store for a OBD II reading, invest in your own code reader. Also, run a forum search for AC trouble codes: simple test.


-->System Self-Test

Some system generated fault codes can be displayed on the control panel screen. When a fault is flagged, an audible “beep” will sound and the message “Er” will be displayed for five seconds, after the ignition is switched to position II. To display stored “panel fault codes”, follow this procedure:

• Switch off the ignition

Press and hold the AUTO and FRESH / RECIRC buttons simultaneously while switching the ignition to position II.

All of the panel LEDs and all LCD segments will flash ON and OFF. Any function LED indicator or LCD segment that does not flash suggests a fault condition within that area of the panel, or with the LED or LCD.

• Press AUTO

The control panel display will flash and scroll through the list of flagged fault codes. A maximum of five codes will be stored and displayed. If 0 is displayed, no fault codes are flagged.

• Press FACE to manually scroll through the fault codes
  When a fault code is displayed, an accompanying beep will indicate if the fault is present. If the code is not

accompanied by a beep, the fault occurred previously.
NOTE: Faults that are present cannot be cleared until the cause of the fault is repaired.

To clear fault codes, press HRW and FACE simultaneously. Wait 30 seconds for the A/CCM to retest the system and reflag any current faults.

• Press PUSH OFF to return the system to normal operation (default panel settings)

Down here in Tidewater, it too is hot and very humid; normally my base model will freeze meat, but struggled yesterday. Works best to shut off outside air when then temperature gets near 100* in high (very high) humidity. Set at 74* it struggled to keep temp below 76*. Once it cooled down a bit, chilled again.

Really need to read the codes to get a sense of RP issue.

What (who) indy are you now using. With my oldest in Alexandria, it would be nice to know who might help if I have an issue up there.

 

UPDATE: The car drove normally today after the hard reset and some battery charging yesterday. I got the saved codes read at a local auto store. What I do not know is when each was occured.. Two misfires, one each at cylinders 3 and 4. A P1313 for “misfire rate catalyst damage bank 1” and the last P1111 for drive cycle complete. I may buy a cheap code reader and see if I can clear those codes and tell the little *******s never to return!

Given that it is running fine and yesterday’s restricted performance warning was the first it’s had that I know of in its 53k miles, can anyone suggest whether I need to bore deeper into this, i.e. have my shop replace coils, plugs or deal with a potential Cat problem or go blissfully on my way until something really nasty happens?

As for the AC performance, I took a garden hose and forced water through the upper and lower grill areas to try to wash off anything that might be reducing the efficiency of the condenser. The AC ran noticeably cooler today when the outside temperature was just hitting 80, and while the output was not frigid when it was 95 out, it kept the interior of the car tolerable.

Eliot

 

Yes sir...a cheap little ELM327 will clear codes with the best of them, and if
you have an Iphone, there is a wide array of software interface that can
really give you a good idea of what is going on.

 

Jim: I ran the AC panel diagnostics in March when I had an instance of what I thought was puny heat output and there were no codes showing. I will try it again, but I did have better luck with the AC today after hosing down the condenser as best I could in an attempt to flush off things that might be affecting cooling. See my earlier note about the codes the auto store found.

I use a little non-name, cash only gas station shop on Backlick Road in Annandale (Backlick Service) for routine stuff, i.e. oil changes and the like. My prior mechanic there was pretty versed in Jags from an earlier gig but sadly had a career ending injury to his dominant hand not long after dropping his health insurance as too expensive. Sad case. I have not used but heard very good things about Merv’s Auto Repair on the east side of 95 just below Springfield. For anything more Jaguar-centric I have begun using London Auto in Falls Church just above Merrifield. It took a couple weeks to get a slot, and another couple of weeks to get the car back but I wasn’t in a hurry and I was the new guy. This was the winter heat issue/new thermostat-aluminum thermostat tower as old plastic one sprung a leak, and they said my axle U-Joints were starting to show wear so I had those replaced since it was my first visit. They also told me it was long past time to replace my tires, which I just did. I was happy with them. Labor rate was $150 per.

 

thank you

 

Eliot, have you solved the RP mystery, yet? From your posts, it appears to have been low voltage. You may have seen some of my posts over that last four years of a trip I did in June of '21, and unbeknownst to me, the alternator was half dead. It would keep the battery charged enough to start the engine, but the voltage never got above 12.6. The car ran good, but I was getting random codes every day, with the most common being misfire on all eight cylinders. With these cars being all "fly-by-wire" the voltage needs to be at 13.5V minimum to operate correctly; 14.5V is the optimum. Also, I was surprised to see that you were between 2,500 and 3,500 rpm with the car in park. Several years ago, someone on here, I think it was Bob G (motorcarman), mentioned that the ECM would limit the rpm's to 2,500 with the the car in park. So, I would get the scanner, and a multimeter, and just monitor it for a while to see if any codes reappear. With the multimeter you can easily check the voltage at the battery and at the false bulkhead on the right side of the engine compartment.

Ya know, every time I see a post from you, I start reminiscence about my time(s) in DC. Very fun town to live in, especially the restaurant scene. My favorite Saturday was a round of golf at East Potomac Park, then a few cold ones and oysters at the Ebbitt.

 

Hey, great to hear from you, Mark. Ah, Old Ebbitts. The one before Clyde’s took over the operation was a real hoot. When I worked in the National Press Bulidng there was a lot of drinking lunch going on there. The one now at 15th and Pennsylvania is really fun as well and the food is a whole lot better. It’s one of my regular stops if company is in town. .

I’ve not solved the misfire problem entirely but suspect indeed it might have been low voltage. I am going to get a scanner to clear the existing codes (2 for misfires, one for cat damage), hopefully one that also reads battery voltage. I had a multimeter but it vanished in a junk room cleaning. I need to put my charger on the battery again as I’ve been struggling with my tire issue for a few days. Maybe tomorrow if it doesn’t look like rain.

Cheers. .

Eliot

 

Mark, checking the bulkhead connections and the megafuses in front of the spare tire for clean, shiny contacts is very important as well as seeing if the braided battery cables are not warm or hot to the touch.

 

Yea, it is. In this situation, we're just checking for good voltage to see if the misfire codes and RP is random or real. Then Eliot can do a test drive over to the Old Ebbitt Grill for a couple of cold ones.

 

UPDATE: (sorry, I don’t know how to edit the topic line). ISSUES RESOLVED AT LEAST FOR NOW. I got an inexpensive code reader (ANCEL AD310 BT I think), read the same codes as referenced above, then cleared the codes. They have not returned over a short period, do not show as stored, and the emissions check came up clean. I am a happy camper just waiting to see the system has reset itself. (1111 if I recall) after whatever the “drive cycle” is. As for the scanner, pretty easy to use if I can make it work.

AC is blowing as cold as it can get after hosing down the condenser. At OAT of 90F, vents are plenty cold. At 100, not so much, but I’m of an age where I stay out of the noonday sun, mad dogs and Englishmen and all that!

Now, to work with our local British shop on the vibration remaining after not one but 2 sets of tires and multiple trips, but that’s in another posting. I couldn’t get an appointment until Aug. 11, the five-year mark of my ownership of this beast.

Thanks to all for the guidance.