The front two O2 sensor connectors are behind and underneath the coil pack. In other words, they're on top of the bell housing. They're close together and easy to get switched accidentally. Your engine will definitely not run correctly if they are disconnected or switched.

 

Excellent point Eric.

 

THanks Eric, so the test would be to switch those 2 sensors. I can't imagine anyoue has been that deep into this thing, but could failed sensors at this point cause the problem. If so how do you test them?

 

The front two O2 sensors are critical. Using an OBDII scanner with live data readout should show the voltages slowly rising and falling in a wave. O2 sensors go bad regularly. They can be purchased for about $60 each.

 

The sensors and the time you say it takes to change to wimpy mode may be linked. When the engine starts, it is "open loop" meaning the ECU uses estimates to control the fuel air mix. Mine will switch to "closed loop" in ten seconds or so sometimes, where the O2 sensors and other sensors are used to compute the ideal fuel air mix. The ECU is deaf (except the knock sensors), can't hear how ragged the engine sounds, if a combination of sensors is bad, the ECU does what they dictate without question up to a point. Your same live data scanner will show open/closed loop fueling. It is normal to drop out of closed loop on wide open throttle (hammer down).

 

Don't switch the sensors. Pull the coil pack out of the way and switch the connectors they each plug into.

It is very possible they are plugged into the wrong connectors, especially if the connectors are just hanging there and not in their brackets.

 

Wouldn't those 2 sensors blow an OBD code? I have a cheapo code reader and cannot anylize real time. I think it'd be more likely a connector is unplugged than they have been switched. All 8 cylinders soot the plugs so again i think unlikely that one bank is rich and the other lean. All the bottom side of the engine is pretty greasy so it doesn't look like the heads were done recently. Although the one odd bolt in the manifold says it has been off. The little fiberglass cover on the Crankshaft sensor was not bolted on properly and in pretty ratty shape and fastener areas are damaged. I'm thinking it has been removed but again really greasy/oily. Sensor area is clean.

 

I think you should look in the classifieds. There was an ad for DI parts blowout, listed among the items was ECU and alarm unit. Buying a married set allows you to plug in both and go without having to get them sync'd.

This is starting to sound like my truck when I got it. The PO had fed 12V directly to the ECU via the CTS plug attempting to diagnose the electric condenser fans. It took me a few weeks of going through what you are doing. I ran into the PO at the super market and he said he "may have fed 12V+ to the ECU by accident". After inspecting the comp I finally found the burned trace on the circuit board. I jumped it with wire and the truck ran fine, but I got another ECU and alarm because I didn't trust either at that point.

You wouldn't have high rail pressure if an injector was stuck open, and you wouldn't have all 8 sooted up if it was 1 injector. I think either the CTS is flaky or the ECU is brain dead.

You have exhausted everything else at this point.

 

Thanks Higgs I am making contact with Lincoln

 

Hello all,
Got the ECU today along with a smaller 3x5x1 green box(security brain?). Are there any tricks to R&R these units. Rave manual says the ECU is either below the washer fluid reservoir or at the passenger kick panel. Where does the green box go? What about the reprogmming I read about. Not supposed to be needed if both are replaced together. There were 3 gaskets(total 6) on the exhaust manifold to head. Do I use all these Rave pictures only 2 total. No gaskets were present at the exhaust pipe to manifold connections (one side had been leaking) Rave shows a gasket there. Any other tips, I may get to this tomorrow. I hope this works.
jd