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Wiring harness for m278 is not replaceable without engine pullout, that reflects in the dealership price. There is a part of wiring running under exhaust manifold on passenger side. New harness cost about 1500.
Personally I would not replace harness, just wash all connectors with brake cleaner and blow with compressed air, and replace camshaft sensors and magnets.
I have two sensors where the plugs were dripping wet, all the others were dry or just a teeny bit of oil. No oil had reached the ECU, yet. No way I'm changing the harness or paying someone to do it so I decided to suck the oil out.
The two problem sensors, Intake 1 & 2, I drilled a hole as you can see, inserted 1/16" tubing and let engine vacuum suck on them. Not much oil has come out, maybe 6 drops total when I checked it, which was after about 90min drive time. Since then, another 90+ min driving it seems barely any more oil has come out but I'll leave it like this for a while. I tapped vacuum from a connection point for the brake booster using the same 1/16" tubing and a small bottle to collect the oil rather than let it get sucked into the main vac line.
I also drilled a small hole in the ECU, in the cavity where the plug attaches to allow air to enter. If not it would likely reduce air flow down my oily wires, or worse, suck oil up the other wires. As long as the eng is on, it's sucking those oily wires. I'll install new sensors once I feel there is no more oil to suck.
I don't see how this would not be a fix for anyone who has oil in their cam wires. Even if you had to drill all four sensors and actuators it would, imo, beat paying the redonklous bill to replace the harness and time without your car. Note the holes are drilled above and between the metal pins so I'm not touching them.
I also wonder about ECU's with oil in them. Seems to me it would only be a little oil and you could simply wash it out? If it happened to me I'd certainly try cleaning it. I've had my ECU open I don't see why it can't be washed, nor do I see why oil would hurt it. Maybe someone here will give it shot and post the results.
I considered another option for the wires, which was to use air pressure at the connector on the ECU to force oil out. I'd need to have an air compressor hooked up and running when not driving it but maybe a few hours is all it needs to blow it out? Maybe it would work better than vacuum, maybe not, but vacuum is what I went with.
Anyway, fyi:
I have two sensors where the plugs were dripping wet, all the others were dry or just a teeny bit of oil. No oil had reached the ECU, yet. No way I'm changing the harness or paying someone to do it so I decided to suck the oil out.
The two problem sensors, Intake 1 & 2, I drilled a hole as you can see, inserted 1/16" tubing and let engine vacuum suck on them. Not much oil has come out, maybe 6 drops total when I checked it, which was after about 90min drive time. Since then, another 90+ min driving it seems barely any more oil has come out but I'll leave it like this for a while. I tapped vacuum from a connection point for the brake booster using the same 1/16" tubing and a small bottle to collect the oil rather than let it get sucked into the main vac line.
I also drilled a small hole in the ECU, in the cavity where the plug attaches to allow air to enter. If not it would likely reduce air flow down my oily wires, or worse, suck oil up the other wires. As long as the eng is on, it's sucking those oily wires. I'll install new sensors once I feel there is no more oil to suck.
I don't see how this would not be a fix for anyone who has oil in their cam wires. Even if you had to drill all four sensors and actuators it would, imo, beat paying the redonklous bill to replace the harness and time without your car. Note the holes are drilled above and between the metal pins so I'm not touching them.
I also wonder about ECU's with oil in them. Seems to me it would only be a little oil and you could simply wash it out? If it happened to me I'd certainly try cleaning it. I've had my ECU open I don't see why it can't be washed, nor do I see why oil would hurt it. Maybe someone here will give it shot and post the results.
I considered another option for the wires, which was to use air pressure at the connector on the ECU to force oil out. I'd need to have an air compressor hooked up and running when not driving it but maybe a few hours is all it needs to blow it out? Maybe it would work better than vacuum, maybe not, but vacuum is what I went with.
Anyway, fyi:
Impressive work, well done.
Unfortunately, capillary action is molecular in nature and will occur in opposition to external forces such as gravity and vacuum.
Replacement of sensors and magnets is the corrective action. Cleaning a saturated harness, or replacing it, is a necessary part of the repair.
Wow, that's a lot of effort. I found oil in all 4 cam sensors and at the large ECU plug. It wasn't causing any issues. I just cleaned out the harness connectors with electric cleaner spray, put in new sensors, and kept going. Checked on it a couple of times since and don't see any oil to speak of.
Oil can't flow up a wire when air is pushing it down. Sure a thin film will coat it but it won't be able to dump into the ecu plug, which was the point. I'd also like to run solvent through it to actually clean it, but unsure which to use because I don't want to ruin the seal on the ECU plug.
I will likely replace the sensors, but I'd rather use solvent first to get all the oil out or it'll pool up in the new sensors and I'll be wondering if they're leaking. Or I may simply leave it like it is and call it good, because why not.
Then there's people with a real issue, with oil in the ECU plug. Most people aren't like me and would just pay to have the harness replaced, maybe the ECU too, but I would never. So if any others feel the same way, this is an option.
It wasn't much effort. Took substantially less time than driving to the dealer and waiting for them to tell me it's $5-10k to fix. The two sensors came right out, no other parts in the way. Can't say that about the others but I got lucky. Drill holes, shove tube in, reinstall. Maybe an hour including the catch can and vacuum tap? For the harder to reach ones I doubt I'd pull the sensor/actuator, I'd likely just drill and insert tube as-is. I think the harder part for most would be finding the tubing, which was scrap I had lying around. I'd imagine McMaster has it?
Most people aren't like me and would just pay to have the harness replaced, maybe the ECU too, but I would never. So if any others feel the same way, this is an option.
It wasn't much effort.
Actually, I think that now most people are NOT paying to have the cable replaced. Many of these X166 models are now old enough and cheap enough and on the second or third owner and are not dealer maintained or serviced, and many (like my 2013) are long past any extended warranty too. The X166 is moving more and more into the DIY community, where creative, inexpensive ideas like this are appreciated. Sure, if you read old comments people are talking about "the dealer said this" and "the dealer said that" but not as much anymore. Thank you for taking the time to share your solution. It's a little risky to drill and insert a metal pipe into the electrical connectors, but the pictures make it look like you did a pretty clean job of it.
Oil can't flow up a wire when air is pushing it down. Sure a thin film will coat it but it won't be able to dump into the ecu plug, which was the point. I'd also like to run solvent through it to actually clean it, but unsure which to use because I don't want to ruin the seal on the ECU plug.
I will likely replace the sensors, but I'd rather use solvent first to get all the oil out or it'll pool up in the new sensors and I'll be wondering if they're leaking. Or I may simply leave it like it is and call it good, because why not.
Then there's people with a real issue, with oil in the ECU plug. Most people aren't like me and would just pay to have the harness replaced, maybe the ECU too, but I would never. So if any others feel the same way, this is an option.
It wasn't much effort. Took substantially less time than driving to the dealer and waiting for them to tell me it's $5-10k to fix. The two sensors came right out, no other parts in the way. Can't say that about the others but I got lucky. Drill holes, shove tube in, reinstall. Maybe an hour including the catch can and vacuum tap? For the harder to reach ones I doubt I'd pull the sensor/actuator, I'd likely just drill and insert tube as-is. I think the harder part for most would be finding the tubing, which was scrap I had lying around. I'd imagine McMaster has it?
Let's try again. Capillary action is molecular in nature, not driven by air pressure or vacuum, or gravity. But rather by molecular attractive forces, aka surface tension. It's not the mechanism of action which you are attempting to counteract. Capillary action is not a problem of a pipe that can be sucked backwards.
I know capillary action, which is why I said a film could coat the wires but it cannot leak into the ecu. At least not via those two leaky sensors I have vacuum on.
Any amount of oil in the wire that would be enough to leak into the plug, would be more than a molecular film and get sucked back. Not my first time doing this redneck mod on whatever misc leaky thing.
I've been hoping someone with a really bad leak, into the ecu plug, will try this and post results. My guess is nobody will, because I've been dealing with car issues for a loooong time and the vast majority of people are scared to try anything outside the box.
ygstraps; nice pix! I was wondering how the hell oil was getting past those things in the first place, now I know. Thanks
I'm not mechanically inclined however, after reading this entire long post, I was able to successfully inspect and replace all of my 4 position cam sensors and 4 magnets.
My SUV did not have any engine codes or miss fires, I decided to verify and notice all my 8 sensor were all soaked in oil heavily and I was concern that it may have going into the ECU. I decided to take on this project for preventative maintenance. I rather spend a few hundred bucks on doing this than a few thousand dollars and dealing with a bigger issue.
Tools: You're going to be frustrated without these tools
CRC Electronic cleaner (use to clean ECU wires that connect to sensor and magnet solenoids)
T30 torx bit (Removal\add cam position sensor)
8mm gear wrench (Removal\add magnet solenoid)
Zip tie cutters (use to cut zip tie that holds the ECU wire going on driver side magnet solenoid)
mini zip ties (use to zip tie back the ECU wires back near driver side magnet solenoid)
74mm 14 flute oil cap wrench (removal of oil filter)
Torque wrench (add back the oil filter cap to 25nm spec = 18.4lbs)
I wanted to document the process but I was in a time crunch to get the family SUV back on the road. The job is very easy with the right tools and looking at the videos. Overal, I was happy that I was able to tackle this job myself and not have to spend a few thousand bucks in taking it to the dealer or indy.
I hope this post helps everyone to tackle this job. If I can do it, so can you!!!
(I can finally add this patch to my shirt)
when you reconnected your ECU, did the fan kick on automatically? Mine is and I’m wondering if I missed a crucial step in disconnecting the batt first?
What is the magic secret to getting the electrical connectors off? I can't get them to release and I believe that I am releiving the locking tab correctly.
What is the magic secret to getting the electrical connectors off? I can't get them to release and I believe that I am releiving the locking tab correctly.
Wiggle.
1. Retract locking tab
2. Squeeze locking tab
3. While squeezing the locking tab, push connector in the insertion direction
4. Wiggle the connector while pushed in the insertion direction and while squeezing the locking tab
5. Remove while wiggling and squeezing the locking tab
What is the magic secret to getting the electrical connectors off? I can't get them to release and I believe that I am releiving the locking tab correctly.
this guy does a good job of explaining the release procedure:
Update:
It's been over a year since my post 153 about sucking the oil out. It has continued to collect oil and the ECU plug is still bone dry. Not sure how long it was leaking before I noticed, or when exactly I did this mod, but obviously over a year.
I don't know how long it takes to go from dripping wet sensor plugs to the ECU plug, but if it was going to I'd imagine it would've happened by now.
04-18-2023, 10:10 PM
