lennyzx11

I bought a 92 F150 yesterday with the 5.0 and E4OD. 4x4.
I limped it home running rich and pulled the codes KOEO.
I got a 116 and a 558.
Checking the Coolant Temp sensor I found it cracked and replaced it.
Checking the EVR Solenoid I didn't find anything visual and went on.
Disconnected Battery for 15 min. (shorted cables together for a few minutes) and put it all together.
Drove a lot better but the CEL came back on. 558 is still there.


1. Checked pos side of EVR solenoid via backprobe. 14.5 volts.
2. Checked across terminals of EVR with meter(calibrated) 34.6 ohms.
3. Checked for continuity from neg side of EVR to PCM connection. 0.6 ohms
4. Pulled EVR off. blew through both sides with finger closing vent tube on top. (after removing cap)
5. backfeed (only for a few seconds) 12 volts from battery to pos and neg on bench and no change. Smacked on bench and an internal rattle started that wasn't there before like a PVC check valve check sound. Blowing through it now caused changes when solenoid was energized and deenergized.
6. Put back together and drove it and ALL WAS WELL ! Codes 111 showed up.


Part two.
Started next morning drove about a mile and CEL come back on.
Code 558.
Went to Oreillys and bought EVR solenoid and swapped it in parking lot. And drove it. Came back on.
No change. Hooked up old one back up, drove it Came back on.
Checked resistance across both EVR solenoids (old and new) 34.6 and 36 ohms.
Pulled ECM, opened it. Checked resistance from EVR negative to PCM connection 33 at the internal board connection and had 0.6 ohms. (continuity)


Though I disconnected the battery neg each time, the 558 is a hard code immediately upon KOEO test. THE CEL isn't on until later which I know the EGR is ignored until certain parameters are set after truck is driven.


Ordered a PCM this morning for delivery tomorrow.


I'm fixing this because I believe that the EGR system does in fact put the truck in "limp home" mode locking the timing and richening the fuel mixture 15%. Or I'd consider blowing it off as it seems to be running well. (I doubt that. I'm already on a mission to find it now!)


Can any gurus tell me if that is a fact or not?


Any other tests I shoulda done before ordering a PCM? I hate throwing parts at something and the running perfect with no codes before the night has me puzzled. I drove the truck about 30 miles to verify that. highway, town, romping on it and a couple of steep grades. Rechecked codes before, during and last thing after. 111 was only thing in memory.


Thanks for any comments. I let you know if the PCM does clear it.

wde3477

IIRC, somewhere along 91-92, the EGR controls were changed to some kind of differential pressure pickup thing, where some members talked about the ports being plugged and needed to be cleaned out. Haven't personally fooled with this type, just remember it being discussed here on the board somewhere.


At any rate, my experiences have been with problems on the feedback sensor located on top of the EGR valve and the vacuum solenoid that controls the EGR valve operation located on the intake manifold over by the driver rear side.


As far as the sensor, I recall it being important to get the right color - e.g. grey, black, white.


Had a problem with the solenoid which had me stumped for a while. Found there is a very small breather filter on the underside that got plugged up. One supposedly can take the solenoid apart and replace it with a piece of that bubbly stuff room air conditioners use, but I ended up destroying it in the process, so bought a new one. This cleared the code at the time.


Hope this helps...

lennyzx11

Just wanted to let you all know that the replacement PCM fixed it. 95 bucks at Oreilly's auto Parts.


I left out one test that I did that should be done before buying a new ECM.


Disconnect PCM 60 pin connector and EVR connector.


Probe from the 60 pin with meter set on resistance(continuity) check with one lead on 33 pin (EVR solenoid) to each of the following to ensure that greater than 10,000 ohms resistance is observed. This ensures that the wires are not shorted together somewhere in the harness to the wire going to the EVR solenoid from the ECM.


I found this test in one of the links here.


From 33
to 37 IGN Power
to 57 IGN Power
to 40 Ground
to 46 Signal Ground
to 60 Ground


Should be open circuits on all checks.
If you plug the EVR solenoid connector back in,(or forget to unplug it) one of the checks will show the resistance across the solenoid coil of the EVR.
20-70 ohms is the specs. My old one was 35 and the new one was 37 FYI.


Trucks is running like a top!