I have to pull my codes; somethings up. I am following the test procedure from the Haynes manual, and consulting fordfuelinjection.com.
I have two questions,...My truck.... 1992 F150Xlt 4.9L E4OD w/AC, 2WD built Nov 1991
1 How do I know if I have a truck with a power steering pressure sensor, this changes the engine running test, where do I look to find this sensor?
2 How exactly should the WOT (wide open throttle) test be performed when prompted by the EEC self test?? Do I put the gas pedal to the floor all the way, or do a quick rev?? I hate the idea of stomping hard on a sick engine in neutral gear. Thx in advance for replies,ladies and gents!

 

Just turn the wheel left and right about 1/4 turn right after the 3 "cylinder ID" flashes come out during the KOER test. If the computer is looking for a PSPS indication, this will provided it. If the computer does not care, it doesn't hurt anything.

When the computer asks for the "goose test" quickly depress and release the pedal. Just stab the pedal with your foot and immediately release -- 3/4 of the way to the floor seems to do it. The engine does not accellerate fast enough for this to feel like you are abusing it -- it might reach 3500 RPM but that is about it.

Be aware that the computer has aggressively advanced the timing and expects to hear from the knock sensor when you do this. You should not be surprise to hear the "death rattle" of spark knock as you hit the gas -- in fact something is wrong if it doesn't knock.

The computer runs this test for at least two reasons:
1) To see if the knock sensor works
2) To see if the TPS sensor registers something more than "idle position"

 

Allright FeFarms thx for being first on the job. I did the test right. Here are the results for the world to see. /...KOEO..pass code 111 / Continuous stored codes.. 327, 328, 332, 452,

327=DPFE or EVP circuit below minimum volt. of 0.2Volts
328=EVP circuit below minimum voltage of 0.24 volts
332=EGR valve opening not detected
452=Computer detected an error in the VSS or PSOM signal during the last 80 warm-up cycles.

KOER codes 225 and 632
225=Knock sensor signal not sensed during dynamic response test
632=Overdrive cancel switch not changing state(E4OD)

Check engine was coming on while running to and from work on the coldest days this year, 8 or 9 degrees in the morning and 17 to 20 degrees coming home.
I can't sense any problems with the truck, acceleration is fine, shifting is fine. Gas Mileage is a little low..maybe.

Darn coolant is missing!!! Down 1 and1/2 inches in the radiator. I'll be very mad if this lousy Jasper engine with 12,000miles on her has popped a gasket from the coolant to the exhaust!!!!

 

Any other tests I can do for the KNOCK SENSOR? I have 4.65 volts reference coming from the 2-wire harness, I banged on the manifold next to the sensor with a big bar and can't see any change in ignition timing using a light. I think this sensor is gone. Any ohm readings or other static tests I can do? Come on Good Buddies.

 

Code 225 -- If you heard the engine knock during the goose test, and got code 225, the knock sensor is bad or the wiring to it is suspect. Banging on the manifold is worth a try, but not as definitive as running the KOER test. Banging may not even work at idle or light loading -- the computer may assume the engine will never knock in this situation. If you didn't hear the engine knock during the KOER goose test, you didn't goose the gas hard enough or there is a problem with SPOUT going to the TFI module.

4.65 volts going to the knock sensor is too high -- it should be more like 2.5 volts. The knock sensor output is biased to Vref/2 by the computer. The other wire to the knock sensor is SIGRTN which should be 0 volts. The knock sensor does not get VREF. Are you sure you were measuring the knock sensor and not something else? If it was the knock sensor, disconnect it and probe the two wires in the harness. Spec for the knock sensor signal is between 1 and 4 volts. Any higher and you could start to suspect a short to VREF or a problem with the PCM.

Code 632 -- Press and release the O/D cancel switch a couple of times after the cylinder ID pulses during the KOER test. This will satisfy the computer and eliminate this code. You are supposed to push the button, step on the brake, and turn the steering wheel as part of the KOER test process.

Code 327, 328, 332 -- Best guess is the EVP sensor is bad. Possible, but somewhat less likely is the EGR valve is sticking closed, or not getting any vacuum. Since you don't report any EGR codes during KOEO or KOER testing, this problem may be intermittant and not a hard fault. Check the wiring to the EVP for chafing, loose connections, etc.

Code 452 -- VSS input suspect. Bad VSS or PSOM. Does your speedo/Odo/cruise control work OK? Does the transmission shift about when it should? I forget which year F150 they switched to the PSOM box instead of providing a separate VSS input. It is close to the year of your truck. Clear the codes and see how long it takes for this to come back. If it isn't too frequent, don't worry too much about it.

 

When measuring the knock sensor I just stuck the probes into the two female plugs, I had 4.65VDC, the sensor was unplugged also. I didn't use chassis ground as a reference, I'm sure I have the right sensor, it is screwed right into cylinder#1 exhaust manifold.
I never heard a knock during the test, I have never heard my engine knock while on the road.

I will disregard code 632, as usual, the Haynes manual left out details. They always leave out just enuf to confuse a person thoroughly!!!

I'll clear the codes and keep an eye on that 452 code, thx.

I guess my next move is new EGR and EVP, the vacuum lines are in great shape. I may have screwed up the EGR during an engine swap, I recall getting some kind of cleaner in the EGR that didn't agree with the rubber boot inside the housing.The original EGR has made it 13 1/2 years and 163,000miles ....I guess it can retire now.

 

The knock sensor should be screwed into the block, although I can't tell you where it is on a six cylinder.