I am looking at an s5 I want to buy, it runs great, pulls hella hard all the way to redline, and its only got 72k original miles. I noticed though, that on one of the reciepts for the last oil change, it said there is gas in the oil, so I pulled the dipstick and I could smell a faint smell of gas. What does that mean?

 

prolly leaky injectors...plus that is normal, to a small extent.

 

Maybe it flooded a few times. Oil should be changed after a serious engine flood, since raw gas goes right past the seals.

 

*wonder if you'll get flamed for using "hella"*

 

"Maybe it flooded a few times. Oil should be changed after a serious engine flood, since raw gas goes right past the seals."

how duz the gas get back into the oil pan?

 

Get the oil analyzed. My car had a fuel smell so I got it analyzed by Oil Analyzers for less than $20. Good thing I did because I had 6% by volume of fuel in the oil. Not good as fuel is not a good lubricant. Not sure why I get so much fuel in my oil ???

 

If you drive hard enough you could get out that way too,driving your 7 like a grandma is actually a no no because if you do the car can't burn it out the evaporative system.Same goes for pistons as well

 

Hmm, compression numbers are fine though, so I dont think its really a problem, just wondering...

 

It seeps past the side seals.

If the numbers are good, and its not smoking too much, go for it.

 

"It seeps past the side seals."

and then....
where duz it go? it can either go out the exhaust or up the intake manifold, right?

 

I just did an oil change on my car. My oil poured out like water, and it reeked of gas smell. I changed my oil 2800 miles before, and it was also very gas-smelling. I figured the previous owner flooded it. But now I changed my oil, and I never flooded the engine. I'm having a hard time figuring out how the heck fuel would get into the oil pan. So for the "seeps through the seals" thing isnt convincing me. Does anyone have a realy good technical answer? I've checked other threads, non of those help'd either.

 

It seeps through and gets between the oil control rings and then gets into the oil.When you flood a rotary gas is all over the chambers and rotor.Have you ever seen the plugs after a good flood.I flooded mine once and the oil was flammable(volitile like gasoline).And if you have leaky injectors your car isn't no longer metering fuel, it just pours in.

 

I guess my injectors are leaking then. Becaus as soon as I did my oil change, this morning I checked my oil, and it was gas smelling again already. Know where I can get some good injectors for cheap?

edit add: actually no, i can't be leaky injectors, i just had the car smogged a month ago, and it passed. anyone else have any ideas?

 

http://www.rceng.com/
Either get new ones mapped by them or get your old ones cleaned and remaped by them.

 

It still could be leaky injectors even if you just had it smogged.

 

thanks, I'll check them out.

 

Can this be done by a Mazda service department at a dealership?

 

mine started this at about 175,000 miles, right after I started premixing...oil "gains" about a quart every 2,000 miles or so, engine still strong...I've been wondering about the pathways, too, and like some of you have said, the chamber compression has gotta be pushing the unburnt fuel past the side seals & oil control rings (that also is is a good indicator of how rich the ECU runs these things...Just keep an eye on it, I'm changing the oil at 2,000 mile intervals now to keep the system lubricated properly...I figure if anything, it's actually cleaning the oil system components for us, as long as the ratio of gas to oil doesn't get too high (they are, after all, just different versions of the same base product)...I'm rebuilding in another 3 weeks, I'll let you guys know if it (new seals & rings) solves the problem

 

Are you also seeing a drop in oil pressure? When I first changed my oil, I noticed my oil pressure was higher. (Because of the fresh oil) Later, as I drove around, i noticed the oil pressure dropped a little, at 2k it seated at exacty 60 on my oil pressure gauge. Then today, it was right below 60 at 2k.

 

no, my pressures are fine- if your pressure drops that much with "thinner" oil, your oil pump rotor clearances are probably bad, or your relief valve is doing some funky things

 

Well, it doesn't drop drastically. I just noticed a slight change. Would it be a good idea to run "thick engine honey"? A thicker viscosity would be a good idea in this case im assuming.

 

why worry about higher viscosity oil if the seals are allowing gas to add to it? Like I said, I think a rebuild will fix it...

 

I've had the same problem with my 88 vert. Initially thought the gas was left over from a bad flood (previous owner...). But I've changed the oil several times and there's ALWAYS gas in the oil. Actually changed the oil last weekend and there's already a faint smell of gas on the dipstick.

Have to change oil often and/or get those injectors cleaned professionally.

I've noticed a very slight change in oil pressure after an oil change too.

 

Yeah I just find it kind of strange. Since I've had my car, it has never flooded. I've been able to turn it off and on right away with no problems, I never have problems starting my car, and my idle is fine. I plan on buying some new injectors in the future anyway.

 

what are good sized injectors? and where/how can they be mapped?