I recently did an oil change on my '95 GLT and noticed the oil smelled like gas and was very thin. I did put in some MMO to clean out the engine, but that doesn't explain the gas smell. Car runs great with no codes. I get decent mileage as well. Does not burn any oil either. Ideas?

 

did the car sit for a while? If it did, that could explain it. Other than that, you gotta question whether or not your rings are going.

 

No, I've been driving it to work almost daily. Trips are usually short, but I have taken it on a few long road trips that should have burned some of that fuel up. It also has no problem starting either.

 

I was thinking bad rings but doesn't appear to burn any oil. Maybe a leak down test is in order?

 

When I removed the oil cap today to check for the smell, I noticed the cam lobes are a slight rainbow of different colors, a sign of overheating. I assume this is due to the diluted oil....

 

If you've got gas in the oil either you're going too long between oil changes and/or you have leaky injector(s).

 

So I've changed the oil and now I'm running 15w40 additive free oil... It has only 300 miles on it and it smells like gasoline. I think the gas is thinning out the oil and causing the loud valve-train noise as well. The car starts fine, runs great, and has new plugs and relativity new cap/rotor/wires. I think I am going to test the fuel pressure regulator. My understanding is that after I shut the car off, the pressure should not bleed out to 0? Please advise...

 

Did you ever to the compression/leak down test?

 

+ 1 on the compression / leak down test. Will tell you a lot.

FPR: there was a thread the last couple of days about fuel pressure; Gdog wrote about testing the FPR.

I would read the spark plugs NGK Spark Plugs USA

Gdog is correct: gas smell can be caused by leaky injectors, which can be cleaned DIY Ford Fuel Injection » Fuel Injector Cleaning or even better outsource them like this Fuel Injector Cleaning and Testing.

Since you say the car runs great, I would exclude the possibility of deposits on intake valves.

Last and most important -- it sounds like you have lubrication problems, i.e. I would not drive the car very much until this problem is fixed.

 

you have a bad injector and the fuel is leaking past the ring DO NOT RUN THIS MOTOR until you fix the injector your motor can explode ! i had this happen on my 383 mopar engine due to a bad diaphram in the mechanical fuel pump BOOM !!! i open the hood and my valve covers looked like a jiffy pop tin and my oil pan looked pregnant . the friction from the oil pump is what made it ignite .pull the injectors and have them tested

 

Compression was good but I didn't do a leak down test due to the fact that it runs great and does not burn oil.

I only smell gas when I take the oil cap off.

I was planning on getting rebuilt injectors in case the FPR is good.

 

if you have enough gas in your oil to thin it out at 300 miles DO NOT RUN THE MOTOR! you more than likely have bad injectors, which is washing down your cylinder walls and going into your oil which is going to excessively wear on the rings and the cylinder wall and everything else in the motor. Take out your injectors and clean them or have them cleaned ASAP.

 

New rings will leak fuel, rings in ANY condition will leak fuel. Fuel in the oil is not a compression problem. It is incomplete combustion/leak.
You probably have one leaking injector and the engine is compensating by running the rest lean to get the A/F ratios right. If you had a leaking FPR etc, you would definitely notice it in fuel consumption.
I also agree that this engine shouldn't be run till you find the problem, it's probably already damaged.

 

Surely, injector is the prime suspect like most here pointed out. But, it may or may not be simply a 1-issue thing. Reduced compression / leaky seals (that may or may not be seen), etc. etc. may contribute some. To what degree? I would like to know, if it was my car....

In cases like this doing a compression / leak-down is good diagnostic practice, along with other very cheap or free tests (like the FPR).

If it was my engine, I would like to know if I f...ed up the engine by running it this way...

 

question I know its an old post why would fuel be in oil if car was sitting for awhile?