Fuel Dilution problem.

[StevieC]

So I just got my RLI sample test data back from Terry (See my other thread) and it was excellent except it had fuel dilution that was a cause for concern. Not exceptionally high, but needs looking into or else I can't extend my OCI's past 7K KM's (4K miles)

I cleaned my MAF tonight using the proper cleaner and rubbed the sensor wires very carefully with a Q-Tip coated in the cleaner. they were very clean already but I did it anyways. Then I sprayed it generously as well.

I also replaced the 2 up-stream 02 Sensors which had 200K KM's (120K miles) and 300K Km's (192K Miles) respectively.

Took the truck for a spin on some errands I had to do and noticed a big difference in performance and my Scangauge seems to be reporting less fuel usage per 100K so I will have to see if this fixes it for my next report.

Thoughts?

 

[digitalSniperX1]

Get some new fuel injectors?

 

[StevieC]

Well seeing as Fuel Injectors are $1200 for a set of 6 from anywhere I have called I wanted to try O2 Sensors and cleaning the MAF first seeing as I have high mileage on them without service/replacement.

The guy at Hyundai said they have never seen injectors cause a problem on them and that their is a guy that drives a sonata that is approaching 400K KM's (240K miles) with original injectors.

That was the other reason why I was thinking it might be some other problem.

 

[digitalSniperX1]

C'mon now, you've not cleaned the MAF or O2 Sensors? You must have some sooty tailpipes!

(I think I recall you telling us your oil was filled with gasoline)

Falling down on the maintenance job StevieC

 

[digitalSniperX1]

I just found a set of 6 for a LOT less.

 

[Steve S]

I am waiting to see if the new parts help. The change in performance seems like a good sign. the scanguage is by linear logic. If so I have one on my Toy P/U and the mpgs are pretty accurate.

 

[Steve S]

Originally Posted By: digitalSniperX1
I just found a set of 6 for a LOT less.
Canada = metric money.

 

[StevieC]

Originally Posted By: digitalSniperX1
C'mon now, you've not cleaned the MAF or O2 Sensors? You must have some sooty tailpipes!

(I think I recall you telling us your oil was filled with gasoline)

Falling down on the maintenance job StevieC

No reason to think there was a problem because my tail pipe is clean, the fuel economy is good and I look after everything else.

I had a premature spark-plug failure so I blamed this until now and now I see that it must be something else because although the F.D. got better it's still on this report after all the plugs/wires were replaced.

I don't clean the MAF or replace O2's until needed because I'm a "If it ain't broke, don't fix it" kind of guy. Hence the reason my water pump is original with 320K KM's (192K miles).

It's not the money or the time... I love my truck!

 

[StevieC]

Originally Posted By: digitalSniperX1
I just found a set of 6 for a LOT less.
Where?

 

[StevieC]

Originally Posted By: Steve S
Originally Posted By: digitalSniperX1
I just found a set of 6 for a LOT less.
Canada = metric money.

 

[digitalSniperX1]

Rock Auto...several other places.

 

[StevieC]

Thanks I will check it out... I only checked local parts stores here.

Are they OEM brand or knock-off after-market?

 

[OVERKILL]

Why would you need injectors? They are a "seldom fail" item; especially on anything I've ever owned (admittedly mostly Ford products).

 

[digitalSniperX1]

They are refurbished OEM (I think) and I am not saying you need to replace them. New are about triple.

 

[StevieC]

Originally Posted By: OVERK1LL
Why would you need injectors? They are a "seldom fail" item; especially on anything I've ever owned (admittedly mostly Ford products).


If I have one leaking down on engine-shutdown or that isn't closing fast enough when spraying leading to a rich burn.

I have never seen bad injectors in Hyundai/Mistu/Kia so I'm inclined to think this isn't the problem and that is why I went with O2's and MAF cleaning first. Then I will replace if no change on my next UOA.

Most likely it is fixed with the better performance and numbers from my scangauge after this.

Originally Posted By: digitalSniperX1
They are refurbished OEM (I think) and I am not saying you need to replace them. New are about triple.


I found original 7-Auto (Korean Brand which are in it now) on Rock-Auto for $41.39 an injector which means we are getting raped up here from our dealers and aftermarket parts suppliers.

 

[digitalSniperX1]

Lol parts from a dealer are not cheap here either but 1200 seems way over the top.

 

[Bill in Utah]

If you sit and idle you'll see more fuel than "normal".

Bill

 

[StevieC]

There was no idling at all other than at lights here/there in my last 2 used oil analysis on purpose to make sure that wasn't it...

 

[OVERKILL]

Comically, my driving style is probably the polar opposite of Stevie's; foot on the loud pedal much of the time. Yet I get ZERO fuel dilution on my used oil analysis, LOL. I'm lucky to see 500Km from a 110L tank if I'm driving in-town a lot.

Stevie: Normally, if you had an injector that wasn't behaving, there would be evidence on the plugs, which you already changed because you thought they were the issue previously, correct? Was there anything abnormal about the plugs? If not, then you likely are chasing the right path with your current course of action. At least in my opinion.

 

[StevieC]

I did have an ailing plug that showed signs that it was a problem. Because I was so close to changing the plugs anyways I pulled them all with the wires and replaced them.

The plug was definitely the problem as the fuel dilution dropped on this UOA versus the last one and I have since had the plug out of that cylinder (5,000 km) and it's clean like the others.

Problem is I have some other problem going on. After tonight it might just have been the O2's as I had 320K+ KM's (192K Miles) on one upstream and 200K+ KM's (120K KM's) on the other because 1 was replaced already so it's quite possible that was the problem. Also the MAF was never cleaned until now. Mind you it looked clean and nothing came off on the Q-Tips pretty much with the cleaner.

Another UOA is the only way to tell for sure... If I'm looking at injectors so be it... The truck hasn't cost me a dime in mileage I have owned it other than maintenance items so I'm fine with it and it's cheaper than a new car...