Another Rough Idle - set screw moved?

[Rearanger]

Meter set to 200k Ohms

Cold reading before starting: 26k
Operating temp reading is : 2.5k

http://repairpal.com/obd-ii-code-p0118

Lots of places to look for this code fix.

 

[MrDonivan]

ECT and EGR Valve were both replaced last fall.

 

[MrDonivan]

Could the EGR Valve Pressure Sensor be throwing this 332 code? I dont mind spending another 23 bucks for the ECT, but the EGR valve is 42 (which was already replaced) and the Pressure Sensor is 53 - but has not been replaced.

 

[Rearanger]

Always test before replace.

 

[MrDonivan]

I am awaiting the Haynes manual so I have the specs I need. Thank you sir, I appreciate the help keeping this old beast on the road.

 

[MrDonivan]

Can anyone confirm if the ECT Ohm ranges are indeed present in the Haynes manual? I am unable to locate the stats for it within the book I purchased. Or the O2 sesor tests for that matter.

 

[Rearanger]

Yea, my Haynes very poor compared with other vehicles. I have the full FSM, expensive but worth it.

I think the operation is the same even if the years are different.

The higher resistance (rich) = colder temperature. 248F = 1.18 Kohms
-10F = 160.31 Kohms

At 194F you should see about 2.8Kohms
At 176F you should see about 3.84Kohms

Ford states variance of 15%. After about 145F the computer stops rich flow.

The O2 sensor is harder as it's voltage switches (very fast) depending on rich/lean from about .9v to .1v with midrange about .45v. Best way is with graphing software. You might be able to just verify heater operation (if heated) and continuity. My FSM does not give pinpoint test value.

 

[MrDonivan]

Turns out my 1994 truck is rolling a '93 engine. My ECT is the round connector instead of the rectangular.

a 94 ECT sensor costs 22 dollars. a 1993 is 45 dollars.

Sounds legit. sigh.

Cold (75 degree air temp) : 26 kOhms
Operating Temp : 2.5 kOhms (taken just below mid point on temp gauge)


Just going to say hell with it and hope the Autozone warranty is still legit and get another one. I replaced it last Sept and there is a 1 yr warranty. I replaced both the top and front mounted Coolant Temp Sensors back then.

 

[MrDonivan]

Bought the 45 dollar ECT - replaced it and no dice, but in the process, I located a vacuum leak so that is probably it. This EGR Pressure Sensor ???

Has 2 mounting bolts to the upper intake - 1 bolt is missing. I recall replacing them both when I did the upper intake gasket, but the lower mounting bolt is missing now, must not have tightened it up properly.... sigh.

Damn it Jim - I'm a geek not a mechanic! lol

Will take the other bolt out and see if I can find a match for it at lowes or something. Will update thread with result. In the meantime I blew out the low beam on a headlight and got that replaced, and still need to figure out how all 4 blinkers are no longer operable, gotta be a fuse under the dash....

 

[MrDonivan]

Issue with COld Idle - - - RESOLVED.

Thank you all.