Limp Mode Issue, Need advise

[fixkick]

Ok, so found a 58B30 computer and got it all plugged in and it started with very high idle and the CEL came on AGAIN..

So check the codes and now it is flashing 14.. Ok cool, I can replace the ECT. Ran to local part store, picked one up, put it in.. Still 14. Ugghh
key off
pull dome  fuse for say 1 minute
 , now 14 is erased by human. (you) most 14 codes are fast to set and fast to clear (5 seconds), and no need to do dome trick but just in case we do.

now dome fuse back in and key on and run engine see if 14 ECT pops again.?
if yes,...
14 means the 2 wires (either ) are cut! (broken end to end) or ECT is bad.  300 ohms hot and at 40f the ECT reads about 5000 ohms if it reads ok on ohms the 2  wires are cut.
I bet you tested the ECT and is good.


but wait,  test #1 is 5vdc. on the ECT pin, red-yellow strip wire key on ECT unplugged.


if ECU produces +5vdc there then 5vdc in the ECU is good (4.75 to 5.25vdc is spec actual)
there is no why any ecu pin B9 ect pin is blown up, I do not believe that short of lightening hitting car. inputs on all ECU are very robust and protected well.
outputs not so good.

or the ground wire to the ect is cut. the gray yellow.
testing 1,2,3...
key on , ECT connected and cold outside say 40F,  meter to battery neg lug, black meter lead (volts) and red test lead , key on, red wire 2.1v  and gray , 0v on ECT ground pin..
if red wire reads 5 the ect is open, if 0v the wire is cut. to ECU.
if the gray wire reads 5v the ground is open.  (we check ground last here )

warning some fake or wrong ECT exist some are switches, not ECT or other oddities.
but you can test your ect in pan of hot water, 180f is 300 ohms and on car if know it is at 180f. (im sure you did but put this here only to be complete)

I think the ECT wiring is  failing,. that is what I think, but your voltmeter can solve that riddle easy.
just 2 tests, both pins to battery neg lug, key on. per above.

14 means ECT is open circuited.


So checked to see if the resistance on the new ECT was in spec, and no issue there.. So now I have to ask did I get a bad ECU..  I DO NO THINK SO.

Any advise. Really would like to get this little guy running as love them.. but this is getting frustrating.  we will find it , for sure.
do not panic or worry or hot wire the ECU,, I think it is some simple cause, wires for sure.

Also know that the ECT plug can fail, the pins or worse the nasty thing that the wire inside the insulation is broken where eyes can not go.
I pull the plug in hand with about  5 lbs of force and see it see the insulation shrinks now, if yes wire is snapped inside,  use ohm meter end to end see same infinity = bad.

you  are getting close,  I am sure.(see schematic)

never see or heard any code 14 or 15 that could not be cured fast. (wires or ECT bad) is 99.9% cause, or no 5vdc out of ECU.
5vdc is ok otherwise huge  numbers of DTC  stored. all that use 5vdc will. if dead. for sure TPS errors max, and iAT if ECU uses it.

most DTCs on this car are DEAD SENSORS.  100% dead as a door nail and 14 too. I call bad wires.