actuator finally bit me

In for answer. We have 2 Acerts also and I'd like see what the repair process is.

 

Flash code 93 could be a few things. You are correct as far as cylinder 3 or 4, but it could be low current, not responding, or high current. You need cat ET to diagnose it correctly by running an intake actuator test and solenoid test.

For not responding, most of the time it is a bad actuator, which are changed in pairs, so you change 3 and 4 at the same time. It is an easy job, but most people don't have a torx set that goes down to T6, which you'll need.

For low current codes, it still can be an actuator, but just as often a bad injector harness, which have a lot of issues and are quite involved to change. How many miles are on your truck? My opinion, is if it's over 500,000, your lucky the harness's lasted that long and should bit the bullet now and change them both.

 

I have had this problem a couple of times with my 05 mxs. If its the solenoid then it's an easy and cheap fix. Just make sure that they put new connectors to the solenoids as well. I had a prob as the solenoid was changed but the connector was not and it wasn't making good connection and I had to get into cat to get a new connector put on. So make sure if it is needing solenoids replaced ( which is what it most probably is) that you get them to put new connectors on as well to save you trouble.
Also maybe consider having them all replaced as I had trouble with two cylinders then not too much later had the same thing with two more cylinders. It may just be worth replacing all the solenoids and connectors at this time if that's what it is. Also get them to have a check of the wiring under the valve cover as it tends to be exposed to rubbing and chaffing , if it looks dodgy then think about getting the harness replaced while you're in there as well.

 

If those iva solenoids are the originals, then they all need replaced regaurdless. cat has updated these to a different style to fix a couple issues. also, while your in the engine and if you have the extra cash ,somewhere around 300.00 last time i done mine, the injector/vva wiring harness under the valve cover spacer should be replaced as the above post mention. if you check the pass through connector plugs, they probley have oil in them.besides that, they get hot and brittle and cause voltage issues. they are two seperate harnesses and arent really that bad to change if you have a little mechanical skillsand some time. get some good rtv silicone and fill the ends where the wires go into the backside of the plug.that helps to keep the oil out.

Just be careful with the torx screws on the solenoids on the actuators. when tryin to take them out, sometimes they can be in there really tight and i have seen guys strip or even break them off in the actuator housing. they are very small and can be an EXTREME pain to get out if they break or strip. new solendoids come with new screws as well, so if you destroy screws while getting them out. make sure the torx socket is a good solid one and not a cheap china bit if you can.

last thing, once you have the solenids off, take some brake clean or good electrical cleaner and spray and clean the oil passages out. i have seen some with really nasty oil and soot caked in and that cause problems also.

Good luck!

 

The actuator kit # is 10R7302, it comes with 2 actuators and 2 different sets of screws, you wil use only 1 set. It comes with instructions, please read them. There are tiny T6 torx screws to hold them together until they're intalled, they MUST be removed when finished.

I wouldn't bother changing any plug ends unless it's a temp fix until you can change the whole harness. The harness's are known to fail and fixing a plug end will only buy time until they all start to go 1 by 1. I've been down that road before.

I made a rig to load test th harness's with Load Pro test leads. We unplug all the actuators, brake solenoids and injectors, power each wire in the harness, then load test and look for voltage drops. If it fails on any wire, it's time for new harness's.

 

Yes, the 4 little torx screws will remove it. The new ones will come with 2 tiny screws in the top to hold them together, they need to be removed once the other 4 screws are tight.

When the harness's go bad, the wires break internally, so the rarely look bad. They usually break at the plug ends, you can tug on each wire in the plugs with needle nose (about 10lbs of force). If they pull apart, the harness is bad. If not, you can clean up the plugs with contact cleaner and give it a try. I'd also unplug each harness where it bolts through the valve cover base and clean that. If there's oil in there, the harness is wicking (another sign that it's on it's way out). The oil wont hurt anything in there, it's just a sign that oil is getting between the wire and insulation, which means that the harness is starting to deteriorate.

With 750,000 and not knowing if it's ever been changed, I'd put it on your things to do list. Changing actuators may solve your problem for now, and they're not a big deal if they fail on the road, but an injector with low current is a bigger issue, so I'd set some time and money aside for in the near future. It is a job that anyone mechanically inclined can handle, it's not a quick job though. On our Pete's, we can do them in about 4 hours now, the 1st one was almost 8.