Skip the auto shop - Our mechanics make house calls

Q: Oil burning off 1 1/2 quarts every 200 miles

asked by on

After my pickup was leaking oil, I replaced all of the gaskets and seals that were leaking. My pickup now has a spotless engine. But after this, the oil kept reducing by 1 ½ quarts every 200 miles. I changed the PCV valve to see if that was the cause, but that did not make any difference. When I looked at the oil, it looks normal in color and consistency and so does the coolant. The exhaust is not smoking. Running a compression test, without oil, was 120-130 psi on all cylinders. It seems to me that burning 1 ½ quarts every 200 miles would be showing some smoke. I am using old oil because purchasing new oil on a constant basis was getting too expensive! I am wondering if perhaps it is running a little rich and that is why it’s burning oil so quickly. What is your advice for fixing this problem?

A: Hello there, thank you for asking about you...

Hello there, thank you for asking about your 1994 Isuzu Pickup. For your vehicle, minimum compression is 114 PSI and all cylinders should read within 70% of each other. So, according to your results, compression is good. My guess is that the clearance between the valve guides and valves is excessive or that the valve guides seals are worn. Either scenario could result in an engine that sucks down oil but still has good compression. Either way, a quart and a half every 200 miles means something is wrong, very wrong. I suggest you have a professional, such as one from YourMechanic, diagnose your low oil problem and repair your truck firsthand.

Was this answer helpful?

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・Fair and transparent pricing

Get a quote

What others are asking

Q: My AC bearings are making noise - what does this mean?

Hi there. I am not quite clear which bearings or other components you may be hearing. The most likely noises coming from the engine compartment would be the AC compressor clutch bearing, and the compressor itself. While the clutch bearing...

Q: How Do the Cylinder Numbers Impact Vehicle Performance and Reliability?

Engines in today’s automotive vehicles come in different sizes and number of cylinders depending on the vehicle size and weight or the work the engine is expected to do. The engine may also be used for performance or for better...

Q: Car stalls, P0685 code

Hello. Most of the time this is caused by one of two things on your vehicle. It is either because the powertrain control module, or engine computer, is failing internally, or the main relay that supplies power to it is...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
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 to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...