2007 Hyundai Sonata camshaft misfire / sludge prob

[melonhead]

Hello!

First let me say I've found this forum to be insanely informative. Actually in some ways there's just too much info which is why I've decided to start this thread to try and keep all the relevant info in one place.

I have a 2007 Hyundai Sonata V6 that I did not keep up with the proper OCI. About a month and a half ago my car began running poorly so I decided to give a little love to it myself and do my own oil change. When I took the filter out it was extremely crusty and brittle. I replaced it with a new filter and some valvoline 5w20 and went on my way. It ran a bit better for about a week and then I got up one morning, started the car and had a blinking CEL. The car ran a bit sluggish and didn't feel right so I turned around and came home.

I took the car to a friend of a friend mechanic and he was unable to tell me much that I hadn't already figured out from googling but he pointed me in the direction of another mechanic who has a proper shop. That mechanic ended up replacing my camshaft sensor and replacing my valve gasket. When he replaced the valve gasket he discovered what he said was a lot of sludge. He said it wasn't the worst he had seen but said it needed to be resolved right away. He also noted that the sludged up oil was clogging the camshaft sensor.

So here's the question, his plan of attack is to drop the oil pan and run some sort of flush at a total price of about $450. I've read so much on this forum and others that I'm wondering if he should be using the flush. I also believe this is a project I would be capable of doing myself. I'm not sure what the brand of flush is that he intends to use but I believe it was in a grayish plastic bottle. I've talked to other mechanically inclined individuals I know and have heard everything from adding any old flush to adding gumout and general talk of generic flushes. My CEL light is on and I believe I've had 2 more misfires in the last couple of weeks. I am due for emissions testing for the first time this year and won't pass because of the CEL.

What would someone recommend I do to both eliminate the sludge / camshaft error as well as get my CEL to go away so I can pass emissions? I'm certain if I can solve problem 1 then problem 2, the CEL, will go away. Am I wrong? Thanks in advance for all of your help!

FILTER HOUSING

 

[yonyon]

You are beyond the point where you can do a quick fix. It may be possible to clean that horribly abused engine without opening it up, but you'd be looking at a timeframe of months to years, not hours to days.

 

[melonhead]

Fair enough. But what steps do I take in terms of months? Also, I don't think the motor would have "years" on it if this problem continues.

 

[clarklawnscape]

id drain 1/4 the oil, add some kerosene to replace the oil, run a few hours and hope for the best

 

[yonyon]

You're going to get a few opinions on that very soon. I don't have one that's worth listening to, but expect:
-Use Mobil1 or Pennzoil oil.
-Use ARX.
-Use Kreen.
-Give up now because you won't get anywhere until you open it up and mechanically clean it.

My opinion, which isn't worth the a half a cent, let alone two being as I've never dealt with a pile of sludge like that:
Change your oil twice at a 1k interval to get the junk off the top, then switch to a 3k interval with Xw40 HDEO and a low dose of Kreen. The solvent should help clean the crud out, but thin the oil which would be a reason to go with a thick one that can handle a lot of [censored].

 

[GumbyJarvis]

Originally Posted By: clarklawnscape
id drain 1/4 the oil, add some kerosene to replace the oil, run a few hours and hope for the best


How about we dont.
Run a high detergent oil in it.
Suggestion would be Rotella T5 HDEO 10w30, >13$ at WM, with a bunch of filters.

Kreen could be a possibility too.

Id Run a 3K short OCI, Replacing the filter every 1K-1.5K

 

[oggb]

You're going to need some kind of solvent to get rid of that much sludge as quickly as you need to. High detergency oil alone might work - six months from now.

 

[OtisBlkR1]

pull the valve cover and clean by hand..

then start a flush, (Kreen's been popular lately) consider more than one.. like 2-3-4 flushes. Ive actually had some luck with "Restore" Brand cleaner..

then use high detergent motor oil/or detergent added to motor oil and do very frequesnt oil changes..

your going to need to change the oil ALOT, as when this stuff starts breaking free it will clog the filter fast..

 

[simple_gifts]

The guys on Car Talk often refer to a device called MotorVac; It could be the time to look for a shop that has one. Might be expensive, but also might be worth not having to try to mitigate the situation yourself.

 

[BearZDefect]

Originally Posted By: OtisBlkR1
pull the valve cover and clean by hand..
...

It is a V6 so there are two of these, and the rear may be partly covered by the intake.

What is the mileage? And if you've owned it since new, how many (or few) oil changes in this period of service did it take to build up that much sludge? I am only curious, not trying to criticize - you already realize the cause and effect by now.

 

[stephen9666]

What was the specific error code or codes?

 

[jim302]

That's a lot of sludge. These engines aren't known for being particularly hard on oil. How long did it go without an oil change?

Unfortunately, there's no good cheap way to deal with this. My suggestion would be to have as much sludge as possible cleaned from under the valve covers, then drop the oil pan and clean it out, along with everything that is easily accessible. After this, perform a flush with something like Kreen and then change your oil very frequently until you are sure it is cleaned up. Cleaning as much as possible before using the chemical flushes will reduce the chance of dislodging a large piece of sludge and causing even more damage.

 

[GumbyJarvis]

Oh and dads L200 looked really similar to this first OC I did on it, I did a 5K OCI, with a 10w30 PHM vs the 5w30 Reccomendation, cleaned it up really nice, so If you DO clean by hand, in a 3K OCI it should be better.