What does the TPS (Throttle Position Sensor) do in a Diesel Delica L300 with EGR Delete?

sck_nogas

sck_nogas

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After fixing the TPS connector problem I had on my 1991 Diesel Delica, I had this question...

What is the TPS doing? I mean I understand it's function, That a TPS "moves with the throttle and sends a voltage signal to the computer indicating throttle angle and speed of movement data. The computer uses this data to measure engine load, adjust timing, fuel delivery, EGR, converter clutch operation and clear flood mode."

But, if the only thing that the TPS on a 90s era Diesel L300 is doing is sending a signal to the EGR, which I've removed. Then apart from having a loose wire in my engine compartment, why should I have fixed it?
 
If it's the right temperature* for the glow plugs to cycle off and on after starting, turning the TPS above the idle position will increase the duty cycle. On my engine it only lasts for about 30 seconds, maybe a minute if I let it sit there and idle rather than driving straight away.

Which reminds me, I really must check the TPS calibration after losing a glow plug: it's possible the plugs have been running too much.

*If it's too cold they just stay on all the time (100% duty cycle) until the engine's warmed up, too warm and they stop glowing once the engine starts.
 
So, if my Glow Plug controller is toast and I just manually cycle them... My TPS is sending signals to
  1. EGR (removed)
  2. Glow Plug Controller (broken)
  3. ??? :p
 
TPS on L300 Star Wahgon with 4D56 EGR delete and ECU bypass does nothing. There are two vacuum control solenoids beside the Fuel Filter that enable/disable the EGR valve that lets dirty exhaust into your Clean intake. I have been inside the Diesel ECU and done countless repairs to leaking capacitors and the end result is the same; delete/bypass and remove all the piping on top of the Valve cover. Plug the line coming from the Alternator vacuum pump. When we do the upgrade to the D4BF Hyundai replacement, we get the engine in with NO EGR system. The AC is usually not working either so I Block the AC vacuum line and the EGR line from the alternator permanently.
 
EGR blanking plate at exhaust then gets an EGT gauge fitting. You need a Exhaust Temp Gauge to see how hot your little diesel is getting on Hill Climbs. Standard Upgrade at my shop...
 
Manual Glow Control is the best way to go. You are now the Diesel ECU!! I usually install a Guarded Aircraft style Switch with LED in the tip. Shows when the Glow Plugs are on..
 

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You can tap into the wires at the GCU and leave it in if you want to.. I usually jumper into the 12v Feed and the 12v O/P from GCU to the Glow Plug solenoid behind the driver seat. These two new wires go directly to the switch and are still controlled by the ignition switch. Safest way,,..
See photos.
 

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