As far as the boroscope, I've been seeing a lot of ads for one that hooks to a smartphone. Looks very promising and quite a good deal. But if you can get your hands on a really good one, (like the Snap-on unit); that's better. I know some of the more recent high end models have an optional head for the probe that can look up and in different directions. You're not really interested in a view of the piston; you want a close look at how the valve is seated.

As far as the decarbonizer set up, where are you located? Close enough to borrow mine?

Just north of Atlanta, so not too far away. :D

Mine came with a mirror attachment, but it was too unstable to risk losing it in the cylinder.

Another Update:

Got the new camera Friday and tinkering with it this afternoon. Much better image quality than the other one I had. Only issue is it's focus distance made it hard to get a good clear image of the valves.

Video of the valves closed - trying to see if they were seated properly - if you're curious: https://youtu.be/2GxCPxO9ZjU

(Didn't see any signs of a bent or burnt valve, just covered in gunk- though I'm certainly no expert)

I've been looking at the kit, but the decarbonization fluid was discontinued (OTC 7904A1). I called OTC and they didn't have any replacement. I've googled around and haven't found anything I'm confident using + buying the kit. Any thoughts?

I found someone on eBay selling 1 can for $80 + $20 shipping :bustingup

I've used MotorVac CarbonClean MV-6

Here's a link: ($11.38)

https://www.ntxtools.com/network-too...=NTX%20Desktop

Thanks! Will be purchasing the kit Friday and see what happens.

In the mean time, I finally got a new OTC compression set, which actually worked. The one I had from Sears now seems much lower in quality.

*Cylinder 1 measured just a hair over 70 dry, I think. 90 Wet.

Attached a pic of Cylinder 2 intake valve for comparison to the other pics previously posted of Cylinder 1. So clean in comparison.

*my son thinks he hit the schrader valve on the gauge before giving me the number, but forgot to tell me until after I did the wet test. So... will do it again before the OTC cleaner/decarb run.

Ordered the OTC 7448A, OTC Adapter 549578 (per OTC should work with 07, 4.8i), OTC 7000A cleaner - 1 can, CarbonClean MV-6 Max Strength - 2 cans. Spent $100 less for all the above compared to just the 7649A kit. The adapter #'s OTC gave me for the X were not listed with that kit and I'm assuming there's no need for the decarbon adapter since the CarbonClean is designed to work through the fuel rail.

If everything comes in before next weekend, I'll do it that Sunday, but the shipping dates for some items range past that time so may have to wait longer.

The plan at this piont:

1. Pick up a combustion leak detector to make sure nothing is found (doesn't appear a single drop of coolant has been lost since the valley pan was changed, but...)
2. Leak down test on Cylinder 1
3. Test compression on all 8 Cylinders
4. Take 'Before' picks of all 8 with boroscope, try to look at valves too
5. Run the 7000A Fuel injector cleaner first
6. Test compression on all 8 Cylinders
7. Take 'After picks' of all 8
8. Run the CarboClean Decarb
9. Repeat compression test/s / take 'After' pics

I know that the fuel injector cleaner probably wont do anything for compression or change the state of the combustion chamber, at least for cylinder 1 since it has a brand new injector, but would be good for others to see separate 'proof' images anyway for both banks.

My assumption is running the fuel injector cleaner first will help maximize the effectiveness of the carbon cleaner solution. ?

Of course, on additional step; pray that one or more of the steps above solves the misfire.

The way this cleaner works is that you shut off the fuel pump, and run the car on the pure solvent. The kit comes with a book that will tell you the pressure to set the device valve at, so you're matching the normal fuel pressure. Or you can put a fuel pressure gauge on before disconnecting the fuel pump and measure the pressure.

The two tricky things are getting the proper fittings to hook up to the fuel rail, and disabling the fuel pump while still allowing the car to run. Pulling a fuse doesn't always do it; some cars you have to physically unplug the fuel pump. I don't know the procedure on the X5. BTW, on the last car I did, (an infinity G35,) the car ran about 1/2hour on one can of solvent. I would guess the X5 is a little more thirsty, so figure 20min or so.

Given that you are burning this solvent instead of fuel, it can definitely have a positive effect the combustion chambers. How much is anyone's guess. Since both the fuel injection cleaner and the decarbonizer are going exactly the same place, I'm also not sure how different their impact will be. I know I have seen distinct drivability improvements from the fuel injection cleaning. But there's a reason walnut blasting is done; the solvent might not be enough. But walnut blasting is far more invasive. It's absolutely worth a try, and the results of your "scientific" methodology will be very interesting.

Finally received the cleaner, so have just done a compression test on cylinders 1-6. 7 and 8 I really don't want to fool with since the fuel and power lines are in the way and just removing the bracket that holds the ignition coils down was frustrating enough to stop. :D

1. 55
2. 195
3. 200
4. 205
5. 211
6. 194

(11 yr old son provided a 'grid' to keep the plugs/coils organized :D )


The adapter for the canister to the fuel line doesn't seem to be correct, so will be calling OTC tomorrow to make sure I have the right one.

Also, I switched plugs 1 and 2 the last time I attempted a compression test and it seems cylinder 2 'cleaned up' the plug that was in cylinder 1, while cylinder 1 'fouled up' the plug that was previously in cylinder 2 (worse than before). :dunno:

Also, one of the first things I did when I picked up this X5 was change out the struts for the trunk and assumed the hood struts needed to be replaced as well. As soon as I hung the empty canister, the hood came down. Thank fully I was prepared. :(

Update: Had to talk to OTC again to get the correct adapter, which arrived today, so did one run of injector cleaner and one run of carbon clean.

On the injector cleaner, it ran like normal, no noticeable difference once I dialed in the right pressure (33psi). The carbon clean ran like I've seen people using stuff like seafoam, where it bogged down, nearly died several times, etc. No smoking out of the exhaust though. I went to run the second can of carbon cleaner but couldn't get it started, so hooked the regular fuel line back up and gave it a quick spirited drive. All the numbers I normally look at didn't seem to be different (INPA, OBD Fusion).

Misfire still there. :(

Also, did a compression test after and will take some pics tomorrow after it's cooled down, and then run the second can of carbon clean through.

Compression Numbers:

Before cleaner / After cleaner

1. 55 / 22 <-- seems strange it went down ??
2. 195 /208
3. 200 /215
4. 205 /210
5. 211 /207
6. 194 /200

(didn't bother with 7 or 8 due to difficulty/laziness with access)


I reset all error codes before and then after all of this, no change, yet.

By far the. most. difficult. part of this process was getting that fuel line disconnected. Next after that would be tying into the fuel line with the adapter, without removing anything from the engine. :D

Rest was easy. Hook up canister, add cleaner/solution, add shop air, get pressure correct, disconnect fuel pump (one relay in the rear cargo area), start vehicle, wait.

Note for anybody who might want to try this in the future: the adapter I ended up with, which worked like a charm, was OTC's 518476, 5/16 Ford Inline Adapter.

Lastly, it did feel slightly smoother and even more so at higher RPMs (3000+).