I have been lurking on the forum for quite some time. I have been searching for an answer to my issue. I have a 2013 LR4 HSE 5.0. I just clicked 105k. My wife decided she wants to keep the truck so I do what any red blooded man would do. I took a perfectly good working truck and tried to do a 100k tuneup.

I replaced injectors, spark plugs, coil packs. It was supposed to be simple. It has been anything but simple. Bank 2 consistently misfires, and bank 1 randomly misfires. If the truck sits for a while it starts and runs perfect. Turn it off and try to restart it, it diesels and wants stall.

At this point in addition to the tune up items, I have replaced bank one valve cover w new pcv valves, fuel filter, low press fuel pump, both hpfp, and map sensor. I have ruled out maf sensors by swapping out w known good sensors.

Fwiw, I can hear the pcv closest to the firewall hissing with the engine burble. If I put my finger on the tiny hole the engine changes idle and almost stalls.

it’s been almost 4 weeks of hell. I hope someone can help.

 

Do you have a GAP tool or other reader for diagnostic codes, fuel trims, etc.? I don’t think that PCV should be sucking air. Sounds like the diaphragm is torn or not seated properly. When the car is at idle, the vacuum should suck the PCV diaphragm closed or nearly so. A leaking PCV will give you a lean condition and rough idle. Check your fuel trims if you have a scanner that can see them. It will show up as a vacuum leak, so lean condition with highly positive fuel trim (at least in closed loop after it warms up).

Hope that’s all it is. I’ve also heard non-oem coil packs don’t play well with these cars - not sure what you put in.

 

Are you using a genuine JLR PCV? I purchased one for speedy delivery from Amazon when the main dealer had none in stock for Land Rover (later realised they had jaguar version in stock). The aftermarket one did not work and caused all sorts of issues including hissing as you describe. Once I had the genuine Jaguar version and compared side by side there were distinct differences and the JLR version was easier to fit and worked perfectly as it should.

 

I replaced bank one valve cover. It came w pcv valves pre installed. I did use aftermarket coil packs, but I have 12 packs to test. I have tried to replicate the issue on other cylinders based on swapping parts. At this point I have got bank one running perfect and bank 2 will run well until the engine gets hot. Then it will start to minor misfire w rough idle. If I cycle the engine it will diesel almost die and kick off the batt symbol on the dash. No solid error codes. I am about to replace the upstream o2 on bank 2. Not sure if that is the right direction. I was also thinking the brake booster might cause some of this as well because I saw some oil in the plenum. Any thoughts or suggestions from the forum will be greatly appreciated. Thanks in advance everyone .

 

Sounds like you have a few leaks to correct. Gaskets, PCV, vacuum lines, Air intake. Not sure why you want to change the upstream O2 sensor without any codes identifying an issue. And cheap aftermarket injectors are never a bargain.

 

Do you have a smoker? I’ve found that working on locating all the vacuum leaks it’s an invaluable tool.