2011 LR4 Misfire/rough idle

[michael weiner]

My 2012 LR4 still going good since fuel injector cleaner, no misfires and no codes. I have noticed, though that in reverse the truck kind of makes a put feel or sound. Only in reverse, and all the time in reverse. Saw possibility this is a strange possibly normal thing in these vehicles. ????

 

[L Crist]

UPDATE: Truck is all good since the LR Dealership swapped out my LPFP and HPFP's. Whew. That cost a fortune but they were able to work out a discount with me on the parts. I am simply glad she's running great on cold start up! Of course though, as soon as I got her home, the driver side door lock actuator went kaput on me.

 

[feathersg]

New to the site. I have owned a LR4 2010 HSE 5.0 for two years now.

A couple of weeks ago I noticed I had a coolant smell but no obvious leaks. I ordered a water pump and thermostat to replace and kept an eye on the coolant. A few days later while driving the vehicle stumbled and threw a restricted performance MIL. I managed to stumble home a couple of miles and parked it. Codes were all sorts of misfires and ran horribly at idle and low battery. I pulled it into my shop and tested the battery - all good - alternator was charging fine - thought maybe I had a high or low voltage issue - easy stuff first. As I started to research other problems, I changed the water pump and thermostat and decided to change the plugs - original with 150000 miles. Buttoned that up and started to tackle the misfire that was still there. That's when I found this thread. I have fluid coming out of my driver's tailpipe, but doesn't smell like gas and isn't flammable - I tried to burn it. The misfire is now showing 1,3,5,7 but that is the passenger side - right? I listened to the injectors with a stethoscope and they are all clicking. The last time I ran it coolant started to leak out around the pump, about a quart, onto the floor. I thought maybe I didn't get the pump or oil cooler tube installed correctly, but it didn't leak until the last time I started.

That's when I saw some people talking about the crossover tubes.... searched on that and my heart sunk. Is it a blown head gasket now? I pulled the plugs again and did a compression check.

2 = 165 1 = 151
4 = 155 3 = 165
6 = 160 5 = 175
8 = 165 7 = 165

I don't see any obvious issues here. They are not perfect, but I don't have the exact compression specs. Is it the injectors?
Obviously the crossover tubes are getting an inspection today or tomorrow as well as a leakdown test. I also plan to check and clean the valves when the intake manifold is off. Any suggestions would help.

 

[DaytonaRS7]

New to the site. I have owned a LR4 2010 HSE 5.0 for two years now.

A couple of weeks ago I noticed I had a coolant smell but no obvious leaks. I ordered a water pump and thermostat to replace and kept an eye on the coolant. A few days later while driving the vehicle stumbled and threw a restricted performance MIL. I managed to stumble home a couple of miles and parked it. Codes were all sorts of misfires and ran horribly at idle and low battery. I pulled it into my shop and tested the battery - all good - alternator was charging fine - thought maybe I had a high or low voltage issue - easy stuff first. As I started to research other problems, I changed the water pump and thermostat and decided to change the plugs - original with 150000 miles. Buttoned that up and started to tackle the misfire that was still there. That's when I found this thread. I have fluid coming out of my driver's tailpipe, but doesn't smell like gas and isn't flammable - I tried to burn it. The misfire is now showing 1,3,5,7 but that is the passenger side - right? I listened to the injectors with a stethoscope and they are all clicking. The last time I ran it coolant started to leak out around the pump, about a quart, onto the floor. I thought maybe I didn't get the pump or oil cooler tube installed correctly, but it didn't leak until the last time I started.

That's when I saw some people talking about the crossover tubes.... searched on that and my heart sunk. Is it a blown head gasket now? I pulled the plugs again and did a compression check.

2 = 165 1 = 151
4 = 155 3 = 165
6 = 160 5 = 175
8 = 165 7 = 165

I don't see any obvious issues here. They are not perfect, but I don't have the exact compression specs. Is it the injectors?
Obviously the crossover tubes are getting an inspection today or tomorrow as well as a leakdown test. I also plan to check and clean the valves when the intake manifold is off. Any suggestions would help.

the liquid coming out of your tailpipe could be water. 100% normal. Its more noticeable in winter as exhaust gases cool faster and condense.

has the car been overheated?
The crossover pipes don't directly cause blown head gasket. its the lack of coolant and overheating that causes head gasket issues.
with 150k miles, you should replace the crossover pipes. they are well overdue. this will not solve your misfires. but obviously solve the misfires before throwing other parts at the car.

those compression test results all seem ok. 1 is a little low, but nothing alarming. they are all within 10% delta.

Its interesting that all misfires are on the same bank. Possibly a HPFP failure.
https://www.landroverworld.org/threads/lr4-front-fuel-pumps.27220/
https://www.landroverworld.org/threads/high-pressure-fuel-pump-question.41999/

 

[jlglr4]

HPFP sounds like something to check. There have been some problems with them in the SCV6 models, not sure about the V8. Also, possibly an O2 sensor or catalytic converter.

 

[feathersg]

Leak down results

2 = 89% 1 = 90%
4 = 25/50/75 3 = 81%
6 = 85% 5 = 94%
8 = 99% 7 = 83%

#4 was concerning. One of the intake valves was leaking all the way around the sealing edge. First pass was 25% so I cleaned it the best I could and then it went to 50%, cleaned once more and cycled a few times and got 75%. The thing I noticed when cycling through the firing order a few times was a clicking noise from the bank 2 valve cover. Once the valves on #4 jumped from fully open to half-closed. This can't be normal. I haven't pulled the valve cover yet. Intake valves were pretty dirty.

 

[ktm525]

How did you clean the valve?

 

[feathersg]

With the valves closed, I cleaned the valve with a plastic scraper to knock off the large chunks of carbon and had a small vacuum tube down in there to clean it up. I then used air intake cleaner to dilute the rest and vacuumed it out. I saw the thread about walnut blasting as an option as well. If i can get this thing running again I plan to run a cleaner through the intake that will hopefully clear up any small deposits lfet behind. My objective was to remove the large debris.


The clicking noise I hear under the valve cover is at 48:06 in this video. Must be normal but I don't know what it is. It is something he references too in the video as two revolutions of the cam and each click is a revolution.

 

[feathersg]

As a follow-up to my issues. I put everything back together and it ran fine again, for a couple of tanks of fuel. I added seafoam the first tank and BG44 the second. The next tank was premium only and my misfire immediately returned. I pulled the codes and again it was 1,3,5,7 misfire. I pulled the trigger and bought 4 bosch injectors from eeuroparts.com along with thew clips.
https://www.eeuroparts.com/Parts/187708/Fuel-Injector-0261500298/

I already had the battery tray and heat shields removed from the previous work. I waited to reinstall them, glad I did. It only took 1.5 hours. I used a similar method to pull the rail as others using a jack. I also used the injector puller to pull and reseat the injectors. Pretty easy, max ten pulls to get them off.

Runs great now. Acceleration is back. It always felt like the clutch was slipping under hard acceleration and all along it was misfiring, but not enough to throw a code. Glad I found this forum. All in all, I replaced my coolant pump, radiator, radiator hoses, thermostat, front and rear crossover tubes, cleaned my intake, intake vales, changed plugs, changed 4 injectors.

Now I have an oil leak...

 

[djkaosone]

With the valves closed, I cleaned the valve with a plastic scraper to knock off the large chunks of carbon and had a small vacuum tube down in there to clean it up. I then used air intake cleaner to dilute the rest and vacuumed it out. I saw the thread about walnut blasting as an option as well. If i can get this thing running again I plan to run a cleaner through the intake that will hopefully clear up any small deposits lfet behind. My objective was to remove the large debris.

I was the one walnut basting and found it to be the only real way to clean them up safely. I walnut blasted, vacuumed, and wiped down with electric cleaner spray (what I had on hand). Harsh dissolving chemicals are typically not good for your intake and shouldn't be poured onto the the valves to clean them, so I'm told. Either way, good job! You got it running again!

As a note, direct injection causes a lot of carbon build up on the valves. The valves cannot be cleaned through gas lines. The workshop manual recommends running bg44k through the intake phlegm. I forgot the intervals, but I'm assuming at least once a year.