Q: Vehicle won't shift into 4th. High rpm at 60 and won't shift but get a pcv code

asked by on September 05, 2017

Car jerks when shifting into gears. High RPM at 60 and above and won't shift into gear but when using a scan tool it pulled up a lean code. What shall I do?

My car has 160000 miles.
My car has an automatic transmission.

Too much air flowing into the intake causes the engine to lean out, as a result of too much air in relation to the fuel and misfire. At an idle, the PCV valve restricts air flow, to reduce this problem. At high manifold vacuum (idle), a spring loaded valve is drawn up and partially restricts flow to the crankcase. The PCV system is relatively simple. An inlet hose connects to a filtered air source. This is used to supply clean air that is drawn through the engine. Most of the time this air is supplied through the engine air filter. On a few designs there is a separate inlet filter that cleans the incoming air for the PCV system only. This filtered air flows through the engine, picking up fumes and vapors. The air exits through another hose, connected to manifold vacuum. The flow of air draws fumes from the crankcase and burns them harmlessly in the engine. This also creates a slight vacuum, relieving any pressure that may build. Negative pressure helps to prevent oil leaks and oil consumption by the engine. The PCV valve also helps regulate the amount of air flow, which helps prevent oil being drawn out of the engine. When the PCV valve is not working correctly, this will cause an imbalance in air flow and vacuum causing the check engine light to come on. This may also cause problems with shifting due to the ECM attempting to identify shift points that are inconsistent with what it thinks they need to be as a result of the lean fuel condition. I would recommend having an expert from YourMechanic come to your location to diagnose and replace your PCV valve.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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

We have a 2003 ford explorer four door 4 wheel drive, the other day her son was backing up and said it felt like he hit something,

If the vehicle rolls in Park, and that problem is not caused by a cable adjustment or linkage failure, that likely means there is a broken mechanical component in the transmission. Often a parking pawl type arrangement is used and...

Periodic TPMS fault

Yes, firmware, the BCM (body control module), temperature outputs, the harness, faulty batteries, could all be potential causes of this sort of intermittent fault. The problem you having is probably not common though because I do not see a pattern...

Van surges and transmission shifts hard. Driving down the road you can feel the engine kick back. Sometimes will die down and cut

Hey there. The transmission control module (TCM) helps regulate fuel efficiency and power while storing information about the transmission system in its memory. A faulty transmission control module may cause a delay in acceleration or erratic shifting of gears. ...

Related articles

The Best Used Cars to Buy if You're Hauling a Horse Trailer
Horse Horse owners need a vehicle with towing capacity. Depending on the size of your trailer and the weight of your horse or horses, you probably won’t be able to get away with less than a 3,000-pound towing capacity, and...
The Best Used Cars to Buy If You’re a Massage Therapist
If If you're a massage therapist, one of the cornerstones of your business has to be that you don’t keep your clients waiting. That means you need a vehicle that’s reliable. You also will have to move your gear, including...
Top Five Selling Cars in Colorado in 2012
Colorado Colorado offers a varied climate depending on where drivers are located. Those in lower elevations see plenty of sunshine all year, while those in the mountain areas can see as much as 300 inches of snow. Due to this,...