Entire bank 2 misfire

[jlglr4]

Fuel pressure shouldn’t affect one bank only. I’d be thinking the vvt or cam solenoid as someone else mentioned, or o2 sensor - except op said fuel trims look okay. Fuel trims checked after warm up I trust - if not, check again warmed up.

The VVTs are oil pressure actuated as I understand it. solenoid opens a valve to let oil pressure adjust cam timing. Oil pressure is also supposed to keep the timing chain tensioners tight. So, while the solenoid is most likely, I’m also wondering if there might be an oil delivery problem on that side of the motor.

 

[Cowinthefog]

Opposite of fun....ha! That's funny.

So it did it agin to my wife again today separated by several hours. This definitely seems to be isolated to cold starts. The second time she said it took 4 tries and still did it, but when I got there as she shut it off for the 4th time, it of course worked fine for me....Murphy's law strikes again! That guy.....

Anyone know of a solid wag to isolate pumps? When using the iCarsoft to look at high and low pressure sensor voltages, LP is around 2.3 and HP is around 1.25. HP reads about 470 in drive and if I goose it a little to 1300 rpm the pressure rises to close to that.

Josh

 

[Cowinthefog]

Jlgl4-I wonder about the electrics as well since it is one bank only. And have only gotten misfire codes-though none today even after two episodes. When I did the timing chains this weekend, everything LOOKED clean and the vvt buttons moved freely as well as whatever mechanism is inside the solenoid on the front covers. I know cleanliness isn't a definitive test, but thought it was a good sign. I don't know how to test those solenoids yet.

 

[jlglr4]

most vvts you just pull them off and put 12v to them - see if they move (or click if enclosed). not sure if these have anything else that can go wrong with them. i haven’t had to mess with them yet.

 

[Cowinthefog]

Still does it intermittently. It only does it at start up idling. Once it has done it and cleared itself, it seems to be fine the rest of the day. It does not always do it first thing in the morning, but the engine does seem to be cold or cooled off. It always does it immediately when it happens. Out of curiosity, I unplugged each of the 4 sensors (cam position and vvt) on bank 2 (driver side) to see if symptoms mimic the issue. The ground is clean and tight there, wire checks good. None had any perceptible affect when unplugged and node codes came up. I put it in drive each time with no issues while unplugged.

Josh

 

[Tapps33]

So, I’m jumping in here as I’ve been trying to diagnose something similar in my 2010 LR4.

So, this started about 3 years ago. I thought I’d get it when I did the chains. FYI, when I did the chains, I replaced the injectors, plugs, coils, can variators, water pump, front and rear cross overs.

Shortly afterward, I got a Bank 2 Sensor 1 cam position issue, and I swapped the position sensor and both intake cam solenoids. Problem solved…or so I thought.

For me, it’s always left bank misfires, and misfires within the first 1000 revolutions.

I swapped coils from one side to the other, put new plugs in it, swapped injectors from one side to the other….still nothing.

I swapped out the LPFP, nothing (but I needed to do that for the recall anyway) then I swapped the HPFP’s out and thought I had it…nope.

Then, I swapped the O2 sensors and the random misfires MOSTLY went away. Then I figured out I had a bad MAF…swapped them out and got rid of the rich mixture codes. Then I swapped the crank pos sensor…no change, then the cam position sensors, all 4, no change. Then I swapped the MAP sensor, and that has helped startup a little, and the rpm’s are now responding to things like the AC being on or turning the steering wheel.

However, it still struggles to start a little when cold, and I officially got the dreaded misfires on 2,4,6,8 and misfires on first 1000 revs again today.

Here’s what I did notice, at least in mine. I didn’t pop the codes until I let it sit for a while at idle on start, then drove away. (It was hot and my son started the car up to cool it down before we got there). As soon as the engine is halfway warm, there’s no struggling to start issues. Although it does high idle a little rough.

I’m pretty much at the point when I’m almost out of ideas. I looked at the temp sensors and they’re all reading the same when the engine is really cold, so I don’t think it’s anything there.

The only things left to check are the exhaust can solenoids and the cats.

I’ve smoke checked this thing, checked voltage after start up (typically 14.2) and done everything else I can think of.

I’m about to compression check and borescope it tomorrow. We’ll see what I find.

All the above is to say, it sounds like we all have similar problems…hopefully one of us will figure it out!!