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Stbd Engine rough when cold

10-8

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Sup Y'all? My Stbd engine starts right up every time and idles fine. But as I raise the throttle it runs rough and RPMs really jump around at cruise speed. Once the engine is at temp, it runs smooth and the same as port side. If it was a carb engine, I would say it is acting like it is running lean. Is there something to look for on the FI engines that is supposed to richen the mix when cold?
 

blacksapphirez

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we have a twinsie haha

I would check spark plugs for gaps and signs of rich/lean fuel mixture.
 

buckbuck

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Good to hear from you @10-8
I would suggest changing the spark plugs. However, this almost sounds like a throttle position sensor. We are here to help you.
 

Neutron

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If it has them(not sure if they do) Air temp sensor or maf sensor dirty
 

blacksapphirez

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If it has them(not sure if they do) Air temp sensor or maf sensor dirty
I don't think these do have MAF sensor... I did the ribbon delete and did not see anything in the intake (outside of manifold)
 

Neutron

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I wasnt sure. Never really looked over my motors to see
 

10-8

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Good to hear from you @10-8
I would suggest changing the spark plugs. However, this almost sounds like a throttle position sensor. We are here to help you.
Yeah, I was going to check the plugs before I took it out again. Pretty new platinums are in there. But being it's only rough when cold, I was looking for whatever sensor tells it the engine is cold and richen the mixture. All engines run different between cold & hot and thought they must have something on there that determines that.
 

buckbuck

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I am not as familiar with the 1.8 liter motors but they have to map the fuel injection with the engine temp. Perhaps an easy start would be to open up the electrical connections and dry them out and put di-electric grease back in. I would think you could pull the sensor and test it. Probably an RTD and maybe a thermocouple.
 
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