Kreen and check engine light.

Status
Not open for further replies.
Joined
Apr 1, 2019
Messages
561
Location
Ohio
My son was back from college which is a 400 mile each way trip. I added a half quart to the 5 quart sump and the other half to a 20 gallon fuel tank. I drove the car approximately 80 miles around town before he headed back yesterday so basically 500 miles on the Kreen. He called last night and said as he was getting home, the check engine light came on. Also said he started the car a little while later and it hesitated but has ran fine all day today. I'm obviously gonna have him go to auto zone and get i it scanned. The cars used oil but never in 111k threw a cel. Anyone have a Kreen related cel or other problem after using it I should be aware of?
 
What car? Keep in mind that many cars use oil for the Variable Valve Timing, etc.. and the kreen may have altered the behavior of this/these systems, and may also have loosened up some crud which, at least temporarily interfered oil flow or fouled up a sensor.

Did the CEL disappear on its own, or is it still there? Either way, it will need to be checked.
 
09 Altima 2.5. He just informed me the light went off after he came out of class. Maybe something in the fuel system burned off and fouled an 02 sensor or something. If the light went out I'm not real concerned at this point. I'll report back if it helped with consumption or if the light comes back on.
 
Often with fuel system cleaners the computer just notices that something different is going on and triggers the CEL. It doesn't necessarily mean something has failed. A fresh tank of gas and most likely all will return to normal.

It may have been slightly overdosed even if the doseage was correct. I had a Lexus that would trigger the CEL everytime I added a FSC. So, I stopped adding them.
smile.gif
 
What issue did you have that caused you use Kreen in the first place?
That being said, I am a true believer in Kreen and have never had a problem with its use. Follow up and have your Son get the code read...…..It should still be stored in memory.
Curious as to what triggered it.
 
Good to hear the light went out, but I think I'd still want to get a code pulled. If it lit, there should be a historic fault in the system which can be read. Autozone and other auto parts shops can usually pull the codes, so you might suggest your son have one of them do so.
 
Probably a gas cap code, I'd check the codes as others mentioned to be certain nothing is wrong. My bet is it had nothing to do with the Kreen.
 
Does your college aged son have a history of failing to tighten down gas caps? Is he unfamiliar with that particular car?
I'd prefer to accept a "giggling prankster" gas jockey leaving caps loose to be passively mean.

I'm thinkin' Char Baby is onto something with "renegade fluids" in the fuel system.

I like what I hear about Kreen but with my luck I'd clog my injectors with "crud putty".

Fuel injector embolisms
 
A loose gas cap isn't gonna magically tighten itself, it takes force to tighten..if anything, a loose cap will become even looser as it rattles around.

What's the viscosity of the oil you added the Kreen to?

Solvents can thin out the oil to the point the ECU throws a DTC. Even though the CEL went off get it scanned and see if the DTC is still stored. It's also possible some sludge temporarily blocked a passageway.

Fwiw, I never ever run a mild solvent based cleaner (like an MMO) more than say 100 miles and I never ever leave in an "engine flush" like a Motor Medic at all beyond 10 or 15mins of idling.

I'm assuming the other half of Kreen was apprx 16oz? Adding that to a filled 20gl tank shouldn't be an issue. I've added that much mineral spirits into gas tanks in the past and never thrown a CEL.
 
Last edited:
The cars an oil burner at 112k or so and was since new, sadly not enough to appease Nissan. I filled the car up before he left and the CEL didn't come on till over 400 miles later which he hadn't got any more fuel so i doubt loose fuel cap. I followed the directions on the Kreen can and did half in the oil and half in the tank. Oil had 3000 miles on it and was PP 10-30. He hasn't gotten the code pulled so I'm not sure yet, cars running fine and no more CEL. For an 09 it's mint and Nissan installed a new cvt under extended warranty so it's now a college car that uses oil but gets 30mpg. I'd be willing to bet some crud in the fuel system loosened up. Nissan had this thing tuned super rich as evidence of the sooty tail pipe. I was hoping that the Kreen would attack it from both ends and slow the consumption down.
 
Same thing happened to me, but i used Seafoam instead of Kreen on an 00 Civic EX. Started the car up after adding it to oil and gas, and also sucked some into the intake through the brake booster hose. Car started fine, started smoking from exhaust immediately, right as i went to give it some gas, it hesitated, skipped and almost stalled then smoothed right out but triggered a CEL, never got a chance to check the code because after about an hours drive CEL light went off. My guess is that all the carbon being burnt off the pistons and cylinders fouled or dirtied the O2 sensor but after letting it get up to temperature and running it a while, it cleaned itself up. But it definitely free'd up a stuck ring or multiple stuck rings because the car stopped consuming oil after that and ran much smoother.
 
Originally Posted by D1dad
Ran the scanner on it and nothing stored. Got me??

Then I'd say you're good to go.. don't worry about it any further.ðŸ‘
 
Originally Posted by Mad_Hatter
A loose gas cap isn't gonna magically tighten itself, it takes force to tighten..if anything, a loose cap will become even looser as it rattles around.

What's the viscosity of the oil you added the Kreen to?

Solvents can thin out the oil to the point the ECU throws a DTC. Even though the CEL went off get it scanned and see if the DTC is still stored. It's also possible some sludge temporarily blocked a passageway.

Fwiw, I never ever run a mild solvent based cleaner (like an MMO) more than say 100 miles and I never ever leave in an "engine flush" like a Motor Medic at all beyond 10 or 15mins of idling...



For sure I would change the oil and filter after running any cleaner that can thin the oil.
 
2008 Nissan Sentra 123,000 miles 2.0L. Fresh oil change with Super Tech 5w-30. Oil capacity is 4 quarts. I put about 14 oz in the oil and the rest in the fuel tank. Topped off the tank. After about 25 miles I got a "Service Engine Soon" light. Drove to Advance Auto Parts and had the codes read. I got 2 PO420 and 1 PO725. I am going to run the tank of gas till empty and refuel before I get concerned.
[Linked Image]

[Linked Image]
 
Last edited:
The service engine soon light went off once the tank got below 1/4. Filled it back up and the light remained off. So I guess it just burned off a bunch of crud?
 
Status
Not open for further replies.
Back
Top