Q: Idles up, burns 1 quart oil every 20sec with no oil leak.

asked by on

Hi there, my father in laws Bonneville blew the plastic portion of his oil sending unit clear off the 1 1\16" thread nut and we replaced it. After that I discovered the car he's ownered for 2 years had not seen an oil change in 8 years total so we did that. Then we got a low oil pressure read on the dash and saw smoke coming from the the engine right valve cover. When we killed the motor and opened the oil fill cap on that valve cover, we heard a relief of back pressure come from thru out the whole motor. I replaced the PCV valve today and checked the oil again and it was close to the max oil level. I started the vehicle and after idling down the normal operating RPMs the car, on its own started to increase rpm from 1,100-1,600rpm and a whining internal noise became gradually louder as the RPMs rose. I killed the motor and checked the oil and it was now at the minimum film line, about 1 1\2qrts down. I don't know if the rings finally gave or what but there are no leaks or dripping.

My car has 213000 miles.
My car has an automatic transmission.

A: You might not have burned that much oil in ...

You might not have burned that much oil in 30 seconds of running the motor but the oil is not draining back from the upper parts of the motor. The sludge that has built up in the motor has clogged the return drains in the heads and oil gets trapped up in the valve covers. You should look in one of the valve covers to see if the engine is sludge blocking drains in the heads. If it is then you may have to clean out both valve covers and heads of sludge and then run cleaner through engine several times to remove some of the sludge build up. If this does not help then rebuilding of the motor is only option.

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Heard a loud noise and the car turned off.

You have had a catastrophic failure of the rear end, transmission, or a component at a wheel. This is a major repair that will first require someone to determine which component failed. To figure this out, I would lift the...

Q: Muffler dragging

Hi. If your muffler has fallen and is dragging on the ground then it more than likely has a broken bracket. It can also be a broken pipe. If you need further assistance, I recommend you have a mechanic, like...

Q: hi do i need to remove the upper intake manifold to change the coil pack on a 2007 montana sv6. one bolt seems to be under the man

The process to remove the coil does not call for the upper intake to be removed. It calls for the upper trim cover only to be removed. You may have to use a small swivel socket with a short extension...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.