Q I have a 2006 Jaguar X-TYPE 2.2 Diesel Premium Sport Estate that was purchased almost two years ago with 84,000 miles and it now has 99,800 miles. I have had a niggling oil leak since I purchased the car. According to the vehicle’s history, the previous owner looked into the leak but failed to establish its source. I have narrowed the leak down to the front right-hand side of the engine (behind the EGR). In addition to this, the engine does not idle properly from cold. I have searched on the Jaguar forums, which suggests the cold idle issue could be my MAF sensor. But an article in the January 2015 issue of CM about a leak on a Vauxhall Vivaro from the diesel leak-off pipe across the top of the injectors could suggest otherwise. I have also noted a slight oily covering in and around the injectors on top of the engine. I do frequent checks of the undertray, which is always covered in fresh oil, mostly on the driver’s side, but I have not noticed a massive drop in oil on the dipstick. Work done so far includes:
- Service and fresh oil every 6000 miles.
- New oil sump (the original was damaged and the seal was broken).
- Crank pulley changed to upgraded version and all drivebelts replaced. The engine plate was inspected and deemed to be fine, because I understand that the crank pulleys can wobble when worn, causing damage to the engine plate/end cover.
- Upgraded intercooler and intercooler pipes changed for silicon. A Jag specialist informed me that, following the drivebelt change, that the intercooler pipes had split.
- New EGR valve.
A My first question is whether you are sure that it is engine oil leaking and not diesel? We often see engines with a slight diesel leak, which appears to be engine oil because the diesel discolours as it washes down the engine. Coupled with the fact that you are also suffering from poor idle when cold, I would carefully check the injector leak-off pipes. The connector relies on a small O-ring held into the injector by a plastic clip and these are a common failure point.
If the leak is definitely oil, there are only a few places it could originate. Unfortunately, due to the amount of work you have already had completed, this may not be easily pinpointed. The most likely area for such a leak would be the timing chain cover. This is fitted using a sealant and it may be the case that the seal has failed, allowing the oil to escape.
I understand that, with the limited access to the relevant area, it can be very difficult to pinpoint an oil leak, but the best method is to clean the affected area and persevere with careful inspection after a short run before the leaking oil begins to spread.
Have A Problem Vehicle? Get In Touch…
Car Mechanics has the answer in the shape of technical editor Steve Rothwell. Email your questions to firstname.lastname@example.org.
Car Parts and Accessories? We can Help!
Looking for a specific car part or accessory? Need help choosing the right part?
Autosessive.com 0844 736 9933 email@example.com