How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Master Class Auto Your Own Question
Master Class Auto
Master Class Auto, ASE - Master Auto Technician
Category: Car
Satisfied Customers: 253
Experience:  20+ years, full time experience. Specialize in Diagnostics & Electrical
13828642
Type Your Car Question Here...
Master Class Auto is online now
A new question is answered every 9 seconds

03 SUBARU OUTBACK WAS 4 QUARTS OVERFILLED WITH OIL,CAME IN

Resolved Question:

03 SUBARU OUTBACK WAS 4 QUARTS OVERFILLED WITH OIL,CAME IN WITH MISFIRE CODES,SKIPS ONLY AT IDLE,COMPRESSION GOOD 175,ANY THOUGHTS
Submitted: 7 years ago.
Category: Car
Expert:  Master Class Auto replied 7 years ago.
Hi,

I've encountered such cases of gross oil over-fill. Generally, I simply drain oil and change oil/filter as required. Refill with proper oil type and amount. Then, remove plugs and spray a small amount of solvent, like fuel injecton-intake cleaner, into plug holes to break up residue a bit. (do not use a lot) I then check air intake boot and pcv for oil "push back". Clean as needed. Install new plugs and dry coils/boots as needed. When you restart it will likely smoke for a bit. Take a good highway run to burn oil off/out. Worse case is you may also have O2 codes now - or soon. They may have been contaminated. But this should really do the trick for you. OK? Thanks!

Master Class
Master Class Auto and 5 other Car Specialists are ready to help you
Expert:  Master Class Auto replied 7 years ago.
PS - My answer above stands.. But realize, if you needed more suggestions after you try that out.. I'll stick with you. See how it goes.

Best,
Master Class
Master Class Auto and 5 other Car Specialists are ready to help you
Customer: replied 7 years ago.
REPLACED,PLUGS ,WIRES,COIL,PCV VALVE,A/F RATIO SENSOR,CAR STILL RUNS POORLY AT IDLE,NO CODES YET BUT SHORT TERM FUEL TRIM READS -27% WHICH I BELIEVE IS WAY TO RICH
Expert:  Master Class Auto replied 7 years ago.
Hi John,

OK - I fully understand. Let's roll through this.. I'm very concerned with a couple thoughts. The Fuel Trim at -27% is telling us the PCM is trying to compensate for a rich mixture. The Negative Value is the PCM SUBTRACTING Fuel. This makes sense. Because for example, if the O2 (or air/fuel ratio sensors) were coated, the PCM "sees" and "thinks rich". And if the engine is leaned too much, it will MISFIRE. Have you inspected the MAF Meter? I feel it may have been coated with oil in a large way - or even (if in smaller way) received droplets, it may be enough to cause this issue since you seem to have replaced both A/F sensors.. I would pull the intake boot and MAF and inspect. If it looks really clean and perfect, you can consider dropping exhaust and looking for oil in exhaust - as that can ruin the new A/F sensors. Also, the catalysts can be damaged too now. (a clogged cat can cause masive problems) It's unfortunate but it's all possible. To summarize and give you things to test: 1) MAF and Intake Boot 2) A/F sensors (front sensors) 3) Exhaust and cats. 4) Aside from this you may need to even check main vacuum tubes at intake for oil intrusion. PCV PIPES too, even though valve is new. Wherever oil went, it can clog/restrict/contaminate and lead to poor engine performance and/or PCM errors based on a "contaminated sensor input" - furnishing erroneous data. OK?

Best,
Master Class
Expert:  Master Class Auto replied 7 years ago.
PS

Read above post but - Please also, if possible, add 1 bottle of Techron fuel cleaner to tank. But make sure tank is 1/2 - 3/4 full. Thanks..

http://www.chevron.com/products/ourfuels/prodserv/additives/tcp.aspx

Master Class
Master Class Auto and 5 other Car Specialists are ready to help you
Customer: replied 7 years ago.

THANKS FOR YOUR HELP,EGR VALVE WAS STUCK HALF WAY OPEN WITH A NASTY PIECE OF BURNT OIL HOLDING IT .CLEANED IT OUT ,NO MORE CRAZY FUEL TRIM NUMBERS AND IDLES GREAT

Expert:  Master Class Auto replied 7 years ago.
Hi John,

Glad this helped you. As I said in above posts, the OIL "worked its way someplace" - where it should not be. What this means - is the EGR being hung OPEN was causing a LEAN engine. I stated with your -27 Fuel Trim, you were lean. I wish I had told you directly, to remove that valve. However, I did get us real close in two ways. I stated you were very lean and that the oil - anywhere it went, can clog/restrict and contaminate. So, there you go, a "clogged" EGR port and the EGR gets hot enough that the oil 'baked itself' into a chunk - and held valve off seat. This made lean engine. I'm so glad you did find it. What a learning experience for you. This is valuable and makes you "think" clearer, on future, tough jobs. Thanks for being nice to work with and have a great weekend! (I'll close this post now as it's satisfied and complete)

Best,
Master Class