Help with 2002 4.6is rough running

[upallnight]

Originally Posted by murf

Thanks for the heads up on that. My cam locks have the cylinder banks etched on the top, so hard to mix them up.

So just to be on the same page, which bank of cylinders are you calling Bank 1 and which bank of cylinders are you calling bank 2?

[murf]

Originally Posted by upallnight

So just to be on the same page, which bank of cylinders are you calling Bank 1 and which bank of cylinders are you calling bank 2?

Bank 1 passenger side.

From the front of the engine: 1-4 passenger side 5-8 drivers side.

As mentioned before, I've done this procedure to 4 M62TU engines. All were done on my personal cars.

[J.Belknap]

IIRC, the TIS cam timing procedure is slightly different for the 4.6, the acoustic continuity test is not performed. Basically the step is omitted. If the procedure was followed correctly, it is possible that the Vanos gear has failed.

I think you're getting close. It seems that intake cam timing on that bank is slightly off....

[murf]

Update:

Pressurized the intake and found a small vac leak coming from the crank vent valve mounted to the back of the intake manifold. I replaced it. It has a small tear in the diaphram.

Still didn't fix my problem. I messed with the cam sensor wheels and now have both cam right in the middle of the expected range. I ran a full diagnostic check with the DIS software and it comes back with lean on bank 1. I checked the voltage at each injector and they all read 3.6v with the key in the run position. So I wonder why just bank 1? I did the intake pressure test again and there is nothing passing air. There is no check engine light.

[Rockit]

I always look at the most common problems first. Check what spark plugs you have...some spark plugs can make it run rough.

I don't know what OEM plug to use but I would try them.

Also how long was the truck not running before you fixed the timing chains? make sure the fuel is good and the fuel filter is good.

[mam4.6]

I've replaced sparkplugs and had a vehicle run terrible, only to find 1 of the plugs had a microscopic crack. Replaced it and it was fine...

[murf]

I installed new spark plugs towards the beginning of this project.

I expected to see 12v at the injector connector. Is the 3.6v telling me something?

Has a fresh tank of gas.

[murf]

just checked the injector plug voltage on my 540 and it is the same.
I get 3.6v on one pin and 12v on the other. same as the x5.
so that's not it.

[David.X5]

Sorry that this is dragging on for you.

After reading through all these posts again, I am starting to wonder if you aren't having trouble with the Vanos gears. When you did the timing chain, did you check the vanos sprockets for play? Did you already do the Beisan vanos repair? Raj is very good about responding to emails - I would suggest you send him a synoposis and ask what he thinks it might be.

I did the timing chain and Beisan vanos rebuild on a 2001 4.4 (just one car for me) and did not have to tweak the timing gears or anything else. Was within limits shortly after starting up.

Cleaning the MAF with the CRC MAF cleaner killed mine. I guess the dirt was all that was holding it together...but that would affect both banks equally for you.

[murf]

I did do the beisan repair on the vanos. it went very smooth this time, got the teflon ring in there the first try

I am beginning to wonder if the air tube that goes from one head to the other could be letting in air into the exhaust. Item 11. That would cause the lean condition I am seeing on the o2 sensors. Once I get it back together I will take the hose off the vacuum operated valve and see if it is pulling in air. I did a full diagnostic procedure with the GT1/DIS software and attached is what came back.