Discussion:
Trim Valves

This unit was running rough. So far we've replaced the plugs, coils, mixer, regulator and vapor hose. It runs great if trim valves are disconnected but as soon as you plug the trim valve connector in it has a horrible idle. If I bypass the valves and leave them plugged in it runs great but the check engine light comes on. Any tips or knowledge on why the trim valves would cause such a rough idle would be great! Both trim valves have been replaced.
  • Posted 17 Apr 2017 23:15
  • By jeremy_u
  • joined 17 Apr'17 - 3 messages
  • Louisiana, United States
Showing items 1 - 4 of 4 results.
It ended up being , that I needed to reset the fuel trim with the laptop. Once I did this, it worked great. Thanks for the reply.
  • Posted 15 Mar 2022 22:21
  • By Jay_Gamache
  • joined 26 Mar'21 - 3 messages
  • West Virginia, United States
Jay gamache
check the mixer (carb), it should have an screw where you can set the CO.

The trim valves are supposed to be set 50/50 (duty cycle), this way they can adjust mixture up or down, setting them to 50/50 value is done by the mixture screw. Diagnosis software is needed to set the duty cycle.
Also, you can adjust the range of mixture setting by adding thin plastic shims under the cone of the mixer.
Daewoo/Doosan had lots of issues with this in their 2-3 series, also different spring rates for the mixer and regulator where available at that timespan.
  • Posted 14 Mar 2022 22:21
  • By Speedfreak
  • joined 24 May'18 - 103 messages
  • Niederlande, Netherlands
.
Hi,
The Doosan Forklift Truck showing error D4 and D6 within 10 second after engine start and also light On which for engine check on dashboard. Please help me for this.
Model: D80S-5
Serial Number: FDB0D-1270-02180
Type: D
Industrial Truck: 2F61
  • Posted 11 Mar 2022 00:42
  • By Syed
  • joined 14 May'15 - 192 messages
  • Sindh, Pakistan
swasiquehussain at gmail dot com
When you disconnect the trim valves the truck is designed to run rich so that's why it runs better-more fuel. I would check for a vacuum leak on the hoses. You can double check those FTV's with an ohm meter (26-28 ohms) and you should not be able to blow through them.
  • Posted 28 Apr 2017 06:05
  • By sirthor1881
  • joined 15 Mar'11 - 24 messages
  • Georgia, United States

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