No Overdrive

[TedDRondeau]

OK, so I've since replaced the ECM & battery that fried on my last long haul. The net result of the failure of the battery & ECM was a power surge that seems to have fried several items, some simple (headlights, turn & tail lights) and maybe some not so simple (radio, cruise control) but the one that perplexes me is that I seem to not have any overdrive now as demonstrated by high tach reading and no difference when I engage/disengage the "O/D Off" button on the dash. I've checked fuses - all OK. What's should I check next?
91. 5 CTD auto

 

[JLEONARD]

Have you looked at the TPS?

 

[TedDRondeau]

no... what would I check? where?
I'm new to CTD's

 

[JLEONARD]

Throttle Position Sensor. On the injection pump. A TPS is not diesel specific in function.

There is a procedure to adjust but I no longer have a manual.

 

[csnider]

The TPS is the little square thing on top of your injection pump with a wire harness connected to it. . sometimes you can adjust it to make a bit more(or less) ressistance to control when (and if) you OD will engage. . give it a good tap first it may be dirty inside. . Also if your speed sensor at the back of your transmission is malfunctioning , OD might not engage. . clean the contacts at the speed sensor if the TPS is not the culprit. . I think I cleaned out my TPS with contact cleaner once to get it working again... Good luck