Hi All, really enjoy reading the forums. Being able to search through issues that other folks have had and their solutions has been extremely helpful. Thanks!

I'm having a bit of a situation here that is baffling me. Any insight to what might be going on would be extremely helpful.

Car: 2002 Jaguar XK8 Coupe (4.0L, V8)
Mileage: 90,500

Recent Maintenance:
Mechanic replaced Thermostat & Coolant & Accessory Belt
New Spark Plugs & Spark Plug Tube Seals (tube seals were leaking on ignition coils and spark plugs)

Issue: My temperature sensor was going into the red after about 15 minutes of driving while the air conditioner was on. When I would turn the AC off, the temperature read would go back to normal. Even though a mechanic recently added coolant, I checked and it appeared to be low, so I added engine coolant. My check engine light has been on for about 2 months.

I just had some maintenance (listed below) where the mechanic told me that after installing a new thermostat, that the codes should clear after some driving and it would go off. So far the check engine light has not gone off.

After adding coolant the temperature sensor is now staying in a normal range.

I hooked up a small code reader that I own and here are the codes that it read:
P0447 - Evaporative Emission System Vent Control Open
P1646 - Fuel Pump Relay No. 2

For P0447 - For P0447 -I had the Cannister Close Valve replaced about 2.5 years ago. I read here one time that P0447 could sometimes mean an issue with the CCV?

For P1646 - From reading on the forums, this may mean I need a new oxygen sensor? https://www.amazon.com/dp/B000CEZT1O...I2Q089W9E8MO8O

There were also some "PENDING" codes, such as:
P0128 - Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
P1000 - Undefined

Any insights to what might be going on would be greatly appreciated! I cleared the codes, added coolant and the car seems to be running well now, but the check engine light is still on.

Thanks!

 

Also, I had the Cannister Close Valve replaced about 2.5 years ago. I read here one time that P0447 could sometimes mean an issue with the CCV.

 

You have several issues to resolve, temperature being the most important. It's possible that the temp. sensor plug is not making good contact or the sensor is defective. It's located in the crossover pipe, the plastic pipie just below the thermostat. Disconnect the plug and clean with electrical contact cleaner. make sure it snaps into place. If that pipe has never been replaced that would be a good idea before it stars leaking. A new one has the sensor installed.

The thermostat should have a little bleed valve at the top, and I hope it's not installed backwards. A drop in fluid for the first few drives after changing the thermostat is usually just from air in the system, but if you still have the original plastic thermostat tower it could be cracked now. Get an aluminum one.

Code P1646 is actually a defective oxygen sensor, the upstream right side. Generic readers often misidentify that code.

You may be right about the CCV, but I think there are other possibilities. I'll leave that for someone who has resolved the code.

 

**Update** Added a new O2 sensor and car is running great, except for the P0447 code. Still keeps popping up. Local garage had the car for 3 weeks and could not figure out the issue. They had multiple mechanics look into it. Occasionally when the car idles at a stop light I'm getting a very slight "fuel" smell...

Any ideas would be tremendously helpful. Thanks!

 

Most possible causes, including several TSBs from Jaguar on the problem are in this thread : https://www.jaguarforums.com/forum/x...s-smell-50466/