My truck has ran like crap since I bought it ('97) and I finally found out whats wrong. I finally got a code to come up and it says 'O2 sensor calibration window out of range'. I have all new O2's and the local shop here says its a problem with the computer and needs to be recalibrated. Does this sound right. He says that the calibration on in my computer is out of range and is not reading the O2's correctly. I have a severe hessitation whenever I let off the gas and coast for a bit (ex. toll booth, off ramp, turning off the cruise, etc). Another question, since it's out of warranty, should I look for a used computer or pay to have Ford do it? I took the tech at Ford for a ride and he agreed it should be recalibrated, but until I have a check engine light, there was nothing they could do under warranty. Now that the warranty is over, I have the check engine light on. Can you help?

Jeff C.

 

What numeric code are you getting? PXXXX?

 

Just like PC's, vehicle computers can be reprogrammed with the bugs removed. You might need the PCM reprogrammed or "Flashed". Did you actually get an OBDII "P" code or was the mechanic simply scanning real time and found it? You might give him a call and look around for TSB's on your truck.

 

No, the code I got was something like P1150 or P1151..I don't remember which one. It was the one that said "O2 sensor calibration window out of range". I am not sure if I can just take it to Ford and have them 'flash' the computer or are they going to drag *** and diagnose it themselves for $1000 per hour just to find out they need to 'flash' the computer. What to do....


Jeff C.

 

How along ago were the new o2 sensors installed and who installed them?

 

I installed them about 2 years ago. I could install new ones if it would help.

Jeff C.

 

Jeff,

Did you get the sensors from Ford parts or from somewhere else. I would think the o2 sensor should be replaced if it has gone outside the calibration range unless Ford has a TSB out because of some problem they have discovered.

On the other hand, maybe something else is the real problem that is causeing the o2 sensor to go outside calibration. See the following link and use the P1130 code as the P1150 will tell you to look at the P1130 code. Look at the possible causes in the right most column. It points at a whole range of components other than the o2 sensor.

http://www.v8sho.com/SHO/TSB0197HO2SServiceTips.htm

 

Thank you very much for the info. I will prolly start with changing out the O2's and also check the fuel reg. to see if it holds pressure after shut off and also my fuel pressure to see if it's where it's supposed to be.

Again, thanks for the great start.

Jeff C.

 

How's the exhaust smell? being a '97 and if you have 150k + you could have a cat failing.

 

P1151 means that you've got an overly rich condition that the PCM is trying to correct by going overly lean. This is on 2-1 HEGO (driver's side, upstream). P1150 means that the PCM has reached it's correction limit and can't go any further, the HEGO doesn't know what to do so it stops switching. That's the "calibration window out of limit."

Start looking for vacuum leaks...follow the PCV valve tube to the rear of the throttle body, make sure it isn't collapsed or rotted out. Make sure you have no vacuum leaks after the MAF. Check for visable fuel leaks at the injectors and regulator. Apply vacuum to the EGR valve with the engine at idle, look for the engine to stumble and maybe stall. Check for exhaust leaks before the O2s allowing outside air to be measured by them.

Standing by...
Q

 

I'll check on the vaccum leaks and replace all 4 O2 sensors with Ford ones. I only have 80k on the odometer so for a '97, it's not to used up. I love the truck, just need to figure this out. Thank you all for the pointers, I will let everyone know what the cure is when I find it.

Jeff C.