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2011 GL 320 CDI, 2004 E320, 2000 C230, 2004 Toyota Sienna
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Discussion Starter #1
Does the 1990 300E have a thermo time switch? If so, where would it be on the engine? I want to replace it as I have cold start problems. If not, what would be activating the cold start valve in cold and damp mornings? Thanks
 

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99-C43, 05-G55K, 71-280SL, 94-E320 CAB
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Does the 1990 300E have a thermo time switch? If so, where would it be on the engine? I want to replace it as I have cold start problems. If not, what would be activating the cold start valve in cold and damp mornings? Thanks
What engine do you have?
Typically the cold start valve is activated by the fuel pump relay on the M103-12V or from the MAS on the M104-24V.
 

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2011 GL 320 CDI, 2004 E320, 2000 C230, 2004 Toyota Sienna
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231 Posts
Discussion Starter #3
300E cold start

What engine do you have?
Typically the cold start valve is activated by the fuel pump relay on the M103-12V or from the MAS on the M104-24V.
I have 124030 chasis and 103983 engine. I checked the MAS (opened it) and all solder joints were intact. I resoldered them stronger). My problem is that in the mornings or after 4-5 hours, I have to crank it 5-6 tomes before it starts to stumble, hasitate and slowly pick up the rev. Once it warms up, it runs very smooth and nice. All electricals ( plugs, ignition wires, rotor, dist. cap, battery, air filter, fuel filter) are new.
The 10 amp fuse in OVP is ok.
Thanks for responding.
 

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99-C43, 05-G55K, 71-280SL, 94-E320 CAB
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I have 124030 chasis and 103983 engine. I checked the MAS (opened it) and all solder joints were intact. I resoldered them stronger). My problem is that in the mornings or after 4-5 hours, I have to crank it 5-6 tomes before it starts to stumble, hasitate and slowly pick up the rev. Once it warms up, it runs very smooth and nice. All electricals ( plugs, ignition wires, rotor, dist. cap, battery, air filter, fuel filter) are new.
The 10 amp fuse in OVP is ok.
Thanks for responding.
If your engine has a combined MAS/Fuel pump relay then checking solder joints will not indicate a thing.
The loop starts with the engine temp sensor which will send a signal to the MAS / Fuel pump relay when it sees temp below a point.
The relay only pulses the cold start valve for a max of about ten seconds.
 

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2011 GL 320 CDI, 2004 E320, 2000 C230, 2004 Toyota Sienna
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231 Posts
Discussion Starter #5
Thanks RBYCC.
I will try to put new engine temp sensor and let you know. Is the sensor with 3 terminals near the cold start valve? My MAS/fuel pump relay are combined.
 

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1989 300 E 96 Dodge Ram 2004 Custom Chopper 2006 Harley Heritage
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If your engine has a combined MAS/Fuel pump relay then checking solder joints will not indicate a thing.
The loop starts with the engine temp sensor which will send a signal to the MAS / Fuel pump relay when it sees temp below a point.
The relay only pulses the cold start valve for a max of about ten seconds.
Does some of the Engine Temp sensors have 2 prongs instead of 3??? I think i have a Cal edition here cause it has the Cal Diagnostig thingy bye the battery!
 

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2011 GL 320 CDI, 2004 E320, 2000 C230, 2004 Toyota Sienna
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Discussion Starter #8
I rewired the cold start with a push button switch and installed it near the foot cover on the left. When I want to start in the mornings or having it sat for hours, I press the switch for 3-5 seconds to open the cold valve to spray gas in the manifold. Is starts good. I had replaced the cold valve, temp sensor, MAS, but did not work.
 
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