CRC intake valve cleaner experience

GP 2004

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2015 CX-5 GT AWD liquid silver
Today I used the CRC intake valve cleaner for the first time. I have 28K miles and have had a rough idle and rough acceleration, so I decided to try an intake valve cleaner and bought the CRC product.
https://www.amazon.com/dp/ (commissions earned)
I followed the rather complicated instructions, warm the engine, introduce the spray into the engine after the MAF sensor, while a second person keeps the engine at 2000 RPM and spray in 30 second intervals. I assumed that meant to spray for 30 seconds and then wait for 30 seconds before spraying again, the instructions were not clear about how long to wait between sprays. When the can is empty raise the RPM to 3000 RPM, but not over 4000 rpm 3 times and then turn the engine off and connect the PCV hose. Again the instructions were unclear about this. Wait for 1 hour and then drive at expressway speeds for at least 10 minutes.
After an hour wait I drove to the expressway and when I accelerated to highway speeds, the engine stumbled and blew out a huge cloud of blue-white smoke, the flashing engine symbol light and the traction control light and the low tire pressure light all came on. The engine went into limp mode and I could barely go 40 MPH. I exited at the next off ramp and when I came up to a stop light the engine was idling so rough I thought that the engine would die, so I put it in neutral to rev it up to keep it running so I could drive home. Then the engine ran smooth and the flashing service engine light turned off! Since the car was running I got back on the expressway and drove back, but the low tire pressure light and the traction control light were both still lit. As I was driving I noticed that I was low on gas, so I stopped and filled up. When I started the car after getting gas all the warning lights were off! A bizarre experience for sure!
The car now runs very good, smooth idle and acceleration like when it was new! I don't know whether to recommend this product or not. The engine runs smooth, but what a way to get there!
 
That limp can be reset by stopping and restarting the car. Pr selecting neutral and quickly restarting (done it to reset a limp mode after a misfire before). I've used it twice with no odd effects.
 
Make sure you use a top tier gas and you may not have to go through this again.
No way at 28k should you have carbon buildup that bad.
 
Not sure gas has anything to do with carbon build up on the valves because the gas never touches the intake valves. This carbon build up is from the PCV system that vents engine fumes into the intake. If the gas was injected into the intake manifold that gas would help to 'wash' the intake valves.
 
Not sure gas has anything to do with carbon build up on the valves because the gas never touches the intake valves. This carbon build up is from the PCV system that vents engine fumes into the intake. If the gas was injected into the intake manifold that gas would help to 'wash' the intake valves.

Right. Blow by and PCV products cause this. Oil catch can helps minimize deposits and maximize power (cleaner air charge).
 
Today I used the CRC intake valve cleaner for the first time. I have 28K miles and have had a rough idle and rough acceleration, so I decided to try an intake valve cleaner and bought the CRC product.
https://www.amazon.com/dp/ (commissions earned)
I followed the rather complicated instructions, warm the engine, introduce the spray into the engine after the MAF sensor, while a second person keeps the engine at 2000 RPM and spray in 30 second intervals. I assumed that meant to spray for 30 seconds and then wait for 30 seconds before spraying again, the instructions were not clear about how long to wait between sprays. When the can is empty raise the RPM to 3000 RPM, but not over 4000 rpm 3 times and then turn the engine off and connect the PCV hose. Again the instructions were unclear about this. Wait for 1 hour and then drive at expressway speeds for at least 10 minutes.
After an hour wait I drove to the expressway and when I accelerated to highway speeds, the engine stumbled and blew out a huge cloud of blue-white smoke, the flashing engine symbol light and the traction control light and the low tire pressure light all came on. The engine went into limp mode and I could barely go 40 MPH. I exited at the next off ramp and when I came up to a stop light the engine was idling so rough I thought that the engine would die, so I put it in neutral to rev it up to keep it running so I could drive home. Then the engine ran smooth and the flashing service engine light turned off! Since the car was running I got back on the expressway and drove back, but the low tire pressure light and the traction control light were both still lit. As I was driving I noticed that I was low on gas, so I stopped and filled up. When I started the car after getting gas all the warning lights were off! A bizarre experience for sure!
The car now runs very good, smooth idle and acceleration like when it was new! I don't know whether to recommend this product or not. The engine runs smooth, but what a way to get there!

You squeezed a giant zit out of the engine.
 
30 seconds per spray... yikes!!!! I thought 2-3 second sprays at a time were the way to go.
 
You definitely had some instructions mixed up. I believe to avoid flooding they recommend spray and wait for 30 seconds. I do not believe it is spray for 30 wait for 30. But anyhow you did really good. Is there anyway you could tell via a scope or something if there was gunk to begin with and if it was gone or reduced after application?
Also a couple of things if you may notice -
the black puff was noticed by others too.
You should see a slight mpg increase if build up was severe - I would guess 1 mpg.
What are your plans on changing oil at this point? - how many miles later will you change it?
Do you notice any reduced RPMS at highway cruising speeds? (the saving mpg part).
 
An opinion on GM forums warns about using CRC in running form like OP did. It argues that debries of carbon build up can damage pistons and cylinders. Also believe that it can ruin the catalytic converter.
It suggests walnut blasting or a manual method to get build up out. It needs a vacuum pump and some tools along with CRC for cutting the build up but it sucks the debris instead. Seems like a progressive method where each turn might loosen some build up.
 
Removing the intake manifold and walnut blasting the valves is really the way to go with direct injection engines. It is also very labor intensive and time consuming. It can be expensive if you don't have the skills or tools to do it yourself.
 
Removing the intake manifold and walnut blasting the valves is really the way to go with direct injection engines. It is also very labor intensive and time consuming. It can be expensive if you don't have the skills or tools to do it yourself.

There is a manual time consuming method that uses CRC as well. For a 6 cyl chevy from colorado forums but seems an interesting take:
Once it is off, look closely into each intake port at the valves themselves. As the engine stopped, there should be 3-4 of the 6 cylinders that the valves are fully closed in, and those you will clean first. Clean around each port with a rag and some brake clean on the rag to remove any oil. Then with wide masking tape (I prefer the blue painters tape) tape off the 2-3 ports that the valves are open in so no debris falls into the cylinders. Then, take a long shaft flat blade screw driver and pry off as much of the deposits as possible with a shop vac to suck out the particles. Blow out with compressed air nozzle and make sure you get as much loose with the screw driver (a long Pic set helps as well). You will NOT hard the metal!! So no need to be worried. Now spray a good amount of CRC/Seafoam/GM induction cleaner, or any brand (all are close to the same ingredients) to soak the valves and let sit for 15-20 minutes to let the cleaner soak in good and loosen further. Do this in each of the ports with valves fully closed. Then take a universal shot gun cleaning kit brushes in a cordless drill (or by hand) and brush all around every inch being careful not to push to hard and break off the brush, if you do it is easy to fish it out. When finished, spray and soak again and move to the next one. If severe, you may need to repeat this several times. Once you have all deposits removed and have sucked out and blown out all residue and debris, then with a socket on the crank pulley bolt, rotate (you can do so if a manual trans in 2nd gear and pushing it to rotate slightly.) until the valves are fully closed in the last 2-3 cylinders and then wipe off around ports already cleaned, and tape them off and clean the remaining ports.

His reasoning for not using CRC on running engine:
Why to never use the engine running solvent method? These may be the same solvent used in the manual method, but when done while engine is running, it swells the deposits and up to 20-40% of them break loose and while most exits out the exhaust port, it gets stuck in, and shocks and shatters the red hot fragile strata inside the catalytic converter damaging it. The smaller hard particles are forced between the piston and cylinder wall, just like pouring a small amount of sand in your throttle body while running, and this scours/scratches the pistons and cylinder walls causing damage. Also, along with these abrasive smaller particles some solvent as well is forced past the rings, and this goes directly into the engine oil and requires an oil and filter change immediately afterwards or a failed (turned) rod bearing is most common following these cleanings. They pare pushed hard in marketing, etc. and to shops and dealer service centers as they are high profit generators costing less than $10 and charging hundreds to the customer, but this we have studied for years, and I would NEVER do one of these on a GDI engine. Now, the older port injection engines created a very soft powdery carbon that these can be safely used on.....but never use such a cleaning on a GDI engine as the higher heat of the intake valves with no fuel cooling them bakes these into a hard abrasive crystalline deposit. Anyone that has performed a cleaning, or when you do, save some of the stuff you first scrape loose with the screw driver and see.

I actually read all reviews on Amazon and someone had Cat convertors go bad. Also look at the recommendation on oil change after using CRC.
Another user on Amazon uses CRC to break loose the deposits and let it sit for an hour to make blasting easier. I really am in agreement. I do not doubt CRC's cleaning ability - but as he says it can damage and the damage can get worse progressively. Most people will not be able to recognize or link CRC usage with late engine failures.


This is the link >>> http://coloradofans.com/forums/185-...alve-cleaning-results-learn-my-mistake-3.html
where above comments were found.
 
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Whats the cost for walnut blasting valves? Can I buy a bag of walnuts, eat said walnuts, then throw shells with bare hands onto my engine cover? :)
 
You definitely had some instructions mixed up. I believe to avoid flooding they recommend spray and wait for 30 seconds. I do not believe it is spray for 30 wait for 30. But anyhow you did really good. Is there anyway you could tell via a scope or something if there was gunk to begin with and if it was gone or reduced after application?
Also a couple of things if you may notice -
the black puff was noticed by others too.
You should see a slight mpg increase if build up was severe - I would guess 1 mpg.
What are your plans on changing oil at this point? - how many miles later will you change it?
Do you notice any reduced RPMS at highway cruising speeds? (the saving mpg part).

As I said, the instructions were unclear to me. I have not driven much since the service. I guess I will change the oil, I was thinking I'd drive a few more thousand miles as I'm only at about 4K since an oil change. I don't want engine troubles, an oil change is cheap insurance. I haven't driven much to check any MPG change. You have scared me now. I am going to change my oil right now.
 
As I said, the instructions were unclear to me. I have not driven much since the service. I guess I will change the oil, I was thinking I'd drive a few more thousand miles as I'm only at about 4K since an oil change. I don't want engine troubles, an oil change is cheap insurance. I haven't driven much to check any MPG change. You have scared me now. I am going to change my oil right now.

Do the oil change but dont worry. You have not done it on a 75K mile engine. You have done it on an engine with many fewer miles. And like the quote said = if the build up is soft no worries.
 
Make sure you use a top tier gas and you may not have to go through this again.
No way at 28k should you have carbon buildup that bad.
Absolutely, you can and will have that much carbon buildup at 28k even 15k. It seems unlikely but once you know why and how the buildup occurs your suspicions will want. With no fuel to clean the back of the valves all the recirculated exhaust gas just cakes on the intake valves.
 
Hello all , first post here,

I did the CRC treatment twice on my '14 cx-5, at 55k and 65 k, the first time when I stated it, it puffed a big smoke cloud, when I took it on the road you could hear the pinging noise the broken loose carbon buildup made, soon after that the dash lit up like a x-mas tree, I lost throttle response and the truck stalled, waited a few seconds and restarted it and everything was fine, no lights, after that engine response was faster and it felt as it had a bit more torque. I did the treatment a second time 10k later, less carbon pinging noise, less smoke, engine didn't stall, every time after the treatment was done the engine was more responsive and smooth, will do another one at the required interval and let you know. Can't say if damage occurred in the engine head or the cat when carbon was dislodged, a leakdown test should be done to verify.
 
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