cyl bal tst=90 but pulled code 136

[ShiftTheDrift]

Okay, I've been banging my head so hard on this one, I've got one helleva sore spot on the `ol noggin.

We warmed up the car last night to operating temperature and ran the 5min cylinder balance test. The results came back with 90..pass of course. However, we're still pulling code 136, a.k.a.:

136 (R) Oxygen sensor not switching/system lean Left or Front HO2S - Fuel control

Does this indicate a bad O2? I'm thinking we're going to check resistance on the sensor this afternoon and/or swap places and run ODBI again to see if the problem changes sides. In the meantime, I'm just looking for a little insight since brand new O2's are roughly $80.00!

 

[HISSIN50]

That can be just a bad O2. If you had a vac leak, weak FP, etc, then it tends to make both lambdas pop a code. The one lambda could have gotten long in the toof (sic) a little before the other, the wiring could be resistive, the sensor could be contaminated, etc.

They switch from .1 to .9 volts several times a second. As they age, their frequency and range diminishes.

FWIW, the CBT and lambda code are really not related. The CBT pass tells you that you dont have a miss, and that is about it (it measures RPM drop as each injector is cut).

I hear ya on the price of O2's. I could use a couple hundred bucks worth of them myself.

Good luck.

 

[mo_dingo]

You should yank all of the spark plugs on that bank and see if that entire side is running lean, or maybe one cylinder is. Could be an injector problem.
Scott