Drive Cycle Issues

[secondnature]

Hello! I own a 1999 Ford Ranger. In October I attempted to take my truck through DEQ and it my results came back "unready". 4 of my OBD sensors were unready for testing (?).

Took it into shop #1, they diagnosed and found that my thermostat was in need of replacing (not keeping engine hot enuf) and that there was a vacuum leak in my fuel injection (repaired that). Once those things done, retested and the computer will not clear these 4 status points. This shop feels it has to do with the computer.

So, was advised by shop #1 to go to dealership and ask about computer reflash. Dealer says that it is probably not computer (he says they rarely have issues...?), but that it appears that the engine is still not up to temp and a Ford-brand thermostat needs to be installed, not a universal thermostat as was installed the week before.

Take truck back to shop #1 and they replace the thermostat with a MotorCraft thermo. Truck is running hotter, but still they cannot clear the computer drive sensors.

Mind you, my check engine light has never went on. I only found out about this issue when trying to take the DEQ test.

Does anyone have any ideas or knowledge on this topic? My truck just needs to pass DEQ. I am not able to dole our major dollars to figure out what is wrong (and not wrong!). shouldnt a shop be able to figure this out?? thanks

 

[secondnature]

***NOTE: the four OBD sensors that are "unready" are the Catalyst, Evaporative, O2 Sensor and O2 Heater. They have not changed wven with a new thermostat (two of them!!) and some vaccuum repair to the injectors.


Hello! I own a 1999 Ford Ranger. In October I attempted to take my truck through DEQ and it my results came back "unready". 4 of my OBD sensors were unready for testing (?).

Took it into shop #1, they diagnosed and found that my thermostat was in need of replacing (not keeping engine hot enuf) and that there was a vacuum leak in my fuel injection (repaired that). Once those things done, retested and the computer will not clear these 4 status points. This shop feels it has to do with the computer.

So, was advised by shop #1 to go to dealership and ask about computer reflash. Dealer says that it is probably not computer (he says they rarely have issues...?), but that it appears that the engine is still not up to temp and a Ford-brand thermostat needs to be installed, not a universal thermostat as was installed the week before.

Take truck back to shop #1 and they replace the thermostat with a MotorCraft thermo. Truck is running hotter, but still they cannot clear the computer drive sensors.

Mind you, my check engine light has never went on. I only found out about this issue when trying to take the DEQ test.

Does anyone have any ideas or knowledge on this topic? My truck just needs to pass DEQ. I am not able to dole our major dollars to figure out what is wrong (and not wrong!). shouldnt a shop be able to figure this out?? thanks

 

[secondnature]

*** Has anyone ever had to replace a computer module before on a Ford Ranger? I just hate to think that I might have to pay out another $700 to have a new module installed, when I have already paid $500 to just "try this and that" to see if it helps.

Frustrating.


Thank you!!