toyoglenn

Im at a witts end and need help just bought a 96 ranger 2wd 2.3l vehicle has a lean miss and very sluggish. I inspected the timing belt and found it was off a tooth replaced the tbelt but miss was still present. I figured I should do plugs and wires(which did not look bad) did that still missing it does have a code p1131 o2 sensor not switching (stuck lean) it seems to me that if the o2 sensor was bad vehicle would run fine until closed loop operation i have also inspected compression 150 psi @ all four cyl. fuel pressure 35 psi suspect possible m.a.f. but on a scan tool i had 3.82 gm/sec at idle and 12.5 at 2500 rpm. if it was ignition related i would expect to see the plugs fouling but thats not hapening. has anybody ran into this any ideas please help

rhandwor

Check the operating fuel pressure and compare it to ford spec's I would suspect a bad pressure regulator. Also check for an egr stuck partially open.

toyoglenn

i did check fuel pressure was 35 psi ford spec is 30 -40 psi and when a vacuum pump was put on egr valve the truck died

rhandwor

I had a thunderbird with a 302 and the egr would stick and the car would stall. I cleaned it good and it would work for a couple of weeks so I went to ford and bought a new one. I think it gets worn and out of line and sticks clean and lube it good if it solves your problem get a new one.
O2 sensors will go bad also they have a heater which goes out and go on the lean side.

toyoglenn

what do you clean egr with carb cleaner or like silicone? also if the o2 sensor is sticking wouldn't it run fine at startup until vehicle enters closed loop? or will that have an effect at start up?
thank you for your help

rhandwor

I used carb cleaner to clean it out real good. Then use some spray greese on the stem on the outside. Silicon might harm your o2 sensor. I think a bad enough leak would effect it some cold. Even a new egr if leaking is cheaper than a new o2 sensor.
Normally an o2 will stall it on startup until the engine is hot. I got some cheap silicon years ago that was not o2 sensor approved. My boy used it on a valve cover and it damaged two o2 sensors.

DonSor

Looks like it's piecemealing you to death. Suggest you have a complete diagnostic test which will pinpoint the problem/s. Lean codes could be 02 sensors or leaking intake manifold which was the cause of my problem at one time.

toyoglenn

I FINALLY figured out the problem and found it completly by accident the camshaft position sensor was bad. The thing that blew me away was the truck still ran with the sensor unplugged! I guess that my experiance with toyota led me to beleive that if there is no cam sensor signal vehicle will not run but i guess you learn new things all the time anyway thank you all for your help