Rick's Free Auto Repair Advice

P0174

P0174 System Too Lean (Bank 2)

If you have a P0174 System Too Lean (Bank 2)  trouble code, read this to understand what it means

Lean codes are incredibly difficult to diagnose. And it’s one trouble code where you don’t want to start throwing parts at the problem. The guys at the parts store will tell you to replace the Oxygen sensor. Nice guess, but probably wrong. They’re assuming that the fuel mixture is correct but the sensor is reporting it wrong. Oxygen sensors DO wear out. But what if the mixture really IS lean? Can it be lean on only one bank (of a V-6 or V-8) engine? You bet. This kind of code screams out for a little diagnostic work. First, check all the vacuum hoses for cracks and correct placement. Next, spray carburetor cleaner around the intake manifold gasket and listen for an increase in engine RPM. Any increase after spraying indicates a vacuum leak.

The Bank 2 indication tells you that the problem is located on the cylinder bank that does NOT contains the #1 plug. That bank varies by make and engine style, so make sure you check the shop manual.

For more information on this repair or any others for your vehicle, buy an online subscription to either Alldatadiy.com or eautorepair.net. Click on this link to compare the two services: Compare Alldata and Eautorepair.

You need a professional shop manual to work on a late model vehicle. And you need access to the latest technical service bulletins so you don’t waste time and money replacing parts that may misbehave due to a manufacturer’s software glitch. Forget about those cheap manuals you find at the auto parts store. They will just lead you astray. Here are the two best online shop manuals around.

Eautorepair.net is really Mitchell On Demand with a consumer style interface.
Get a 1-Month subscription (31 Days) for $16.99, 1-Year (Best Value!) for $25.99, or a    4-Year (Best Value!) for $39.99. I like the wiring diagrams in Eautorepair.net better than the hard-to-read factory diagrams on Alldatadiy. However, Eautorepair.net doesn’t show how to remove trim or door panels. Alldata does.

AlldataDIY.com is simply Alldata with a consumer style interface. They have a different pricing model. But a 1-year subscription for $26.95. Add additional vehicles for $16.95 for a year. Or, buy their 5-year subscription for $44.95. Add additional vehicles for $29.95 for five years.

© 2012 Rick Muscoplat

Posted on by Rick Muscoplat


Custom Wordpress Website created by Wizzy Wig Web Design, Minneapolis MN