I have heard that it will get tops of pistons really clean. So, I bought it!
Thanks Amazon!

I purchased this for a rough idle issue on my girlfriend's Jeep Wrangler. I decided on this instead of Seafoam because it is specifically recommended in the factory service manual. After first removing the air tube from the throttle body and making sure there was no carbon buildup on the idle air control or throttle plate I fired up the jeep and applied per the can instructions. If you are using it solo like I did wear gloves, as you have to hold the throttle slightly open to keep the engine from stalling - it takes longer than you would think to empty the can, and the intake manifold gets pretty hot. If you have a helper just have them goose the throttle a little if the engine is sputtering. After sitting for a few minutes get on a road where you can get up to 50 mph or so and hit 3000 RPM a few times to blow the crud out of the system. In my case this helped the rough idle considerably, but did not completely cure it. I ended up having to change spark plugs a few weeks later to completely eliminate the issue, but this was worth the money, especially for a high mileage engine (in my case around 150,000). This will probably not do much good for a newer vehicle. Oh, and you may get a check engine light due to "fuel mixture too rich" if you don't keep the RPMs high enough to get enough air flow, but it should self clear after a few driving trips, or you can disconnect the negative battery cable and it will reset.

It is what it is, however by following directions on can it did nothing for my 97 wrangler 4.0l.

Cleaned carbon from combustion chamber very well, easy to use

I have used this on every vehicle I have owned regardless if it was Chrysler or not. I have used Seafoam many times as well and personally I think this does a better job for the few extra dollars. Surprisingly I have been able to buy this at the stealership cheaper than Amazon sells it (go figure). MCCC is great though. I do a treatment typically once a year (usually during the first oil change of that new year) and it smooths out any rough idles or an idle that has a little stumble to it. I never had a vehicle that I slacked on the routine maintenance though so I can't tell you 100% truthfully if its a miracle fix for heavy carbon build ups.

1. Drive the vehicle until the vehicle reaches operating temperature.
2. Remove the air tube/intake that connects to the throttle body (be careful not to damage the wiring/sensors that may be attached)
3. With the engine at an idle, spray the entire contents of MOPAR Combustion Cleaner, P/N 04318001, directly into the throttle body. Allow the vehicle to load up with the cleaner to the point of almost stalling out. DO NOT LET THE VEHICLE STALL keep the idle around 1000-1200 RPM. This is much easier with two people since newer vehicles use electric drive-by-wire throttles and not a manual one. Keep this in mind when doing this. If you have a drive-by-wire throttle body DO NOT force the throttle body blades open with your hand. You can damage this part easily by doing so.
4. Shut the engine OFF after the entire can is ingested into the vehicle.
5. With the hood closed and the vehicle parked inside the garage, allow the vehicle to soak for 1-2 hours. This will ensure that the engine will maintain its temperature and will allow proper solvent penetration.
6. Drive the vehicle on a highway/freeway that will allow the vehicle to be driven safely at the posted speed limit. Upon entering the highway/freeway, accelerate hard to the posted speed limit and maintain speed. Slow down and then perform 5 to 10 Wide Open Throttle (WOT) upshifts. Continue driving at the maximum speed limit for 1-2 miles