Check eng light
Thread Starter
8th Gear
Joined: Jun 2010
Posts: 8
Likes: 0
From: Raleigh NC
Check eng light
I get a check engine light that goes out after about 200 miles. The dealer checked and found code P104 and 107 I believe. Lt and RT bank lean. They could find nothing wrong except the dip stick was pulled out a little. This has happened before so I told them to install a now "O" ring and see if it happened again. How does the check engine light know the dip stick is not seated all the way in. Is it engine case pressure low. Why does the dip stick work its way out. I have 124K miles on the car but it does not use any oil nor does it smoke so I do not think the case pressure is high. Any ideas.
John
John
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
John
The engine crankcase is sealed and ventilated by the Positive Crank Case Vent valve (PCV ) The PCV allows a very slight vacuum to be drawn on the crankcase during part throttle operation.
If the dip stick is being blown out of the tube, you either have a bad defective PCV valve ( CLOGGED ) OR the rubber fitting that connects the PCV to the intake manifold is cracked/deteriorated and leaking manifold vacuum.
The vacuum leak can cause a bank lean condition.
OR
You have excessive piston ring blow by caused by worn or carbon clogged up compression rings.
Recommend that you carefully examine all the tubing and rubber fittings on the entire PCV pluming!
Bill
The engine crankcase is sealed and ventilated by the Positive Crank Case Vent valve (PCV ) The PCV allows a very slight vacuum to be drawn on the crankcase during part throttle operation.
If the dip stick is being blown out of the tube, you either have a bad defective PCV valve ( CLOGGED ) OR the rubber fitting that connects the PCV to the intake manifold is cracked/deteriorated and leaking manifold vacuum.
The vacuum leak can cause a bank lean condition.
OR
You have excessive piston ring blow by caused by worn or carbon clogged up compression rings.
Recommend that you carefully examine all the tubing and rubber fittings on the entire PCV pluming!
Bill
Thread Starter
8th Gear
Joined: Jun 2010
Posts: 8
Likes: 0
From: Raleigh NC
John
The engine crankcase is sealed and ventilated by the Positive Crank Case Vent valve (PCV ) The PCV allows a very slight vacuum to be drawn on the crankcase during part throttle operation.
If the dip stick is being blown out of the tube, you either have a bad defective PCV valve ( CLOGGED ) OR the rubber fitting that connects the PCV to the intake manifold is cracked/deteriorated and leaking manifold vacuum.
The vacuum leak can cause a bank lean condition.
OR
You have excessive piston ring blow by caused by worn or carbon clogged up compression rings.
Recommend that you carefully examine all the tubing and rubber fittings on the entire PCV pluming!
Bill
The engine crankcase is sealed and ventilated by the Positive Crank Case Vent valve (PCV ) The PCV allows a very slight vacuum to be drawn on the crankcase during part throttle operation.
If the dip stick is being blown out of the tube, you either have a bad defective PCV valve ( CLOGGED ) OR the rubber fitting that connects the PCV to the intake manifold is cracked/deteriorated and leaking manifold vacuum.
The vacuum leak can cause a bank lean condition.
OR
You have excessive piston ring blow by caused by worn or carbon clogged up compression rings.
Recommend that you carefully examine all the tubing and rubber fittings on the entire PCV pluming!
Bill
I just left Hendricks Chev who should be very good on Corvettes, they sell about 30 a year and they could find nothing wrong except the dip stick pulled out. I thought they would have checked the PCV valve and maybe they did. I will continue to monitor. Thanks again
John
Instructor
Joined: Aug 2009
Posts: 193
Likes: 0
From: Northern Alabama
Regarding potential leaks in the PCV line, see my post on what I found when I removed my PCV line this week - see the condition of the rubber at the y-joint that was out of view behind the intake ... 140,000 miles so I guess I can't complain too much 
https://www.corvetteforum.com/forums...errerid=341022
https://www.corvetteforum.com/forums...errerid=341022
