97 Ranger throttle cuts out?

[troutski]

Hi HiveMind,
This one has me totally baffled. 97 ranger 4.0 lots of miles, it runs well. Driving along at a constant speed, it feels like everything shuts off, pump the throttle, and all back to life. It does NOT throw a code. All the electricals stay on, gages, dash lights, etc, so not electrical, per se. Doesn't seem like a common TPS failure. Will stay dead until the throttle is pumped. As in, let off and reapplied. The constant throttle has no effect This one really has me stumped.
Any ideas?


Thanks,

Mark
97 Ranger 5 sp 4.0 4x4 XLT 245K miles

 

[RonD]

Welcome to TRS

TPS is a 5volt sensor, works like a volume control or light dimmer, a variable resistor
Computer sends it 5volts with key on, and gets back .69-.99v with throttle closed, and 4.5-4.8volts with throttle wide open
Computer uses this along with other sensors to adjust air/fuel mix
When you take your foot off the gas pedal while cruising, so TPS voltage drops, the computer shuts off the fuel injectors to save on gasoline, until engine RPMs are down to 1,500 or so then it turns them back on to idle levels

So there could be a dead spot on the TPS where voltage suddenly drops, so injectors off, when you move TPS again voltage comes back

This is all a guess of course, you are there we are not, but if it seems to happen with gas pedal at a certain place it would point to TPS, it wouldn't set a code because computer just thinks YOU took your foot off the gas pedal