93 940 codes

jim234 · Post by **jim234** » 24 Feb 2009, 14:23

Hello

I have figured out the fuel injection diagnostic codes on my 93 940 Turbo. They are reading:

231 Adaptive fuel trim to lean or to rich in part load range
113 Short term fuel trim (Lambda control) too lean/rich

does anyone know if I can adjust this myself or is it a sensor that needs replacing?

Thank you for any help

Jim

Post by **billofdurham** » 24 Feb 2009, 15:22

Welcome to Matthew's Volvo Site.

Both codes are pointing to a possible fault in the heated oxygen sensor (HO2S).

1-1-3 could be caused by a short circuit to earth (ground) or in the cables to the HO2S. Check the cables for a possible break in the insulation.

2-3-1 is a little more complex as it can be running lean or rich. If it is running lean it may be caused by a faulty HO2S, an air leak or low fuel pressure. If it is running rich it may be caused by a faulty HO2S, high fuel pressure, contaminated oil, a leaking injector, an exhaust leak or a leaking canister purge valve.

Bill.

jim234 · Post by **jim234** » 25 Feb 2009, 16:45

Thank you Bill

I have ordered the sensors just to have on hand. Friday I will see if I can figure her out.

Thanks again

Jim

jim234 · Post by **jim234** » 03 Mar 2009, 17:52

So, I found an old dried out vacuum hose that was connected to the exhaust system. Replaced it, checked and cleared the codes. Check engine light went off. Good to go! Passed the inspection. I was happy to return the $280 worth of oxygen sensors.

Thanks for you help

Jim

Post by **billofdurham** » 04 Mar 2009, 12:36

Thanks for the update and congratulations on a 'Cheapo' type repair.

I have split your other query into a separate topic as it relates to a different model.

Bill.