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Slightly rough idle in neutral - noob question

Hey guys,

Very new to performance cars. My cars to date were a 1983 BMW 6 series, 2005 GMC truck, 2010 VW CC(heavily tuned), 2013 F150, 2013 Boss... Anyway, my Boss has a very slight rough idle - I almost can't even say it's rough but don't know how else to describe it. The rpm dial doesn't move between individual tachs, but it also doesn't stay perfectly at one position. Is this normal? Is it how a big v8 should act?
 
Sounds like the lopey idle to me. ;) Mine's isn't the smoothest idle I've ever had but I wouldn't call it rough. Take it to your dealer and have them look at it.
 
Do you have the track key installed ? You should have 2 keys with your Boss a black and a red one , the track key is the red one. Ford puts a program into the car computer and one of the TK function is a lopey/rough idle...If not The Boss engine is pretty smooth at idle
 
Compared to the WRX I had. The BOSS is very smooth at idle. It does need a few minutes to warm up so you may be experiencing the 'fast' idle. Does the issue last beyond a few minutes?
 
NFSBOSS said:
Sounds like the lopey idle to me. ;) Mine's isn't the smoothest idle I've ever had but I wouldn't call it rough. Take it to your dealer and have them look at it.

Mine has always had a slightly shaky idle since I bought it. It almost feels like a slight miss, but the engine has yet to throw a code. Took it back to the dealer when it was less than a month old and got the "it's a performance car, not a Lexus" comment. I still don't think it's 100% right, even though it hasn't gotten any worse over the 4k miles I've put on it.
 
I don't have the trackkey installed - so it's with the regular key...

Also it does occur after the car is completely warmed up.

Again, it's not a rough idle necessarily, but you can certainly feel the engine movement. I'll take it in and see if I can get something other than the "not a lexus" comment. Thanks for the replies.
 

NeuRon

2012 500A #1626
108
0
I think I know exactly what you're talking about. I experienced what I think is the same thing and just chalked it up as being a civilized but perceptible reference to what the Lopey Idle of TracKey would be like. A little 70's programmed in.

It was, as the TracKey magnified it greatly. ;D. Same rhythm, etc. Activate the TracKey and see if you find the same when using the red key. I bet you do.
 

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