Gas smell on dipstick!?

Question

I am looking at a 1500 silverado with a Z-71 package. It is a 2003 model with 67,000 on it. Fully loaded LT. I pulled the dipstick and could smell a faint odor of gas on in the oil. The tail pipe show black soot in the pipe. The engine is a 350 vortex. Any help here would be nice. I am looking to buy this truck from a dealer.

Peter

Answer 1

That engine is probably running rich for some reason.Could have leaking injectors.

Answer 2

I would bet that it is just common blow by. All vehicles have a certian amount of blow by meaning that when your engine is on it's compression stroke the air fuel mixture will allow microscopic amounts pass between the cylinder wall and piston rings. The more compresion you have the more fuel will pass by blow by. If the vehicle has been sitting longer than normal on a dealers lot the smell can be stronger due to the fact that the gas is lighter than oil and tries to seperate. as for the soot in the tail pipe i would agree that winter ideling is probally the problem or the truck may be mostly short trips. Bigger the engine the more soot will be present due to the amount of fuel required to run the truck. I would take the truck to a local mechanic and have it looked over before buying any vehicle I decided on. The 350 chevy engine is a proven design and is one of the most reliable engines out there. Then only problem i can think that those trucks have is a fuel pump and fuel sending unit problem that if it does break your looking at 650 dollar repair.

Answer 3

Running rich will cause both the gas smell in the oil, and the black soot in the tailpipe. Since it's now winter, this could be caused by the cold weather - the engine needs to run rich while warming up (in the old days, this was called "running on choke") - and it takes a lot longer to warm up when its this cold. On short trips (to the store, school, etc.), the engine probably doesn't reach operating temperature. This also means that the engine oil is still fairly cold, and the little bit of gas that gets into the oil doesn't have a chance to evaporate.

With so much running cold and rich running, it's no wonder the pipe is sooty and the oil smells like gas. If the smell of gas is strong, this could indicate that the piston rings are worn out (a simple compression test can confirm this), but if it's faint, I wouldn't worry too much about it.

Answer 4

the black soot and the gas smell on the dip stick means that the engine is running very rich (using too much fuel) and this is probably the reason why its being sold. There could be electrical problems with the cars computer system. A truck like this will not pass emissions and will get very poor gas mileage.

Answer 5

Well ofcourse ask him about the gas smelling oil dipstick, but usually that means that a oil ring on the pisting isn't doing such a great job in removing the oil from the cylinder walls... So eventually you may be burning large amounts of oil...

Answer 6

Have the oil analyzed. A sample can be pulled, and it will tell you if there is gas in the oil. Black soot means that the truck is running rich.

Answer 7

hi! i certainly have a ninety 3 GMC Safari van with the 4.3L CMFI (vin w) V6 engine, and that i'm extremely firmilar with the disaster you're having with your Blazer. From what you discribe, it feels like between the classic warning signs of a nasty gas injector. The nickname for the gas injector is stated as a "spider". it relatively is approximately as huge as your fist, has 6 hoses related to it, and it relatively is located decrease than the plenum on the appropriate of the engine. The injector additionally has a geared up in gas tension regulator which isn't replaceable. meaning in case you like a clean regulator you will ought to replace the whole injector. as quickly as the injector gets worse the automobile would be beginning greater stable, working warmer, burning greater gas, emmiting a nasty exhaust smell, and blackening your engine oil quickly! I drove with a nasty injector for rather much a year. It grow to be form of stressful, yet i had to get it replaced through fact the automobile grow to be hesitating relatively undesirable. From what i heard the injectors final approximately 50,000 miles.

Answer 8

gas smell on the oil dip stick could be from a few rerasons, the most commin are that some one flooded the engine and it just needs to be changed, but the most commin on the vortec motor is a bad fuel inlet pipe that leeds to the fuel injectors, this is a costly repair nad could cause motor damage if not taken care of.

Answer 9

Don't get it, it'll blow up eventually!!




Seriously now, you looking for advice on how to negotiate a deal? Oil smelling of gasoline is normal. Gas goes two places: Into the oil (a small ammount although) and out of the tailpipe. Expecially now that it's winter and the cars been idled more, the gas doesnt have a chance to burn off.

Answer 10

Excessive idling as well as repeated cold starts would cause that, and it's pretty much normal. On a malfunction side, I would look at the O2 sensor(s) first.