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Topic: What is a "Rolling Idle" exactly? (Read 1638 times) previous topic - next topic

What is a "Rolling Idle" exactly?

while chatting with a somewhat accquainted mechanic for some advice while i get the hang of troubleshooting my emmisions stuff he asked me if what i had was a "rolling idle" :wtf:
after asking him what does that mean exactly he said i should know already by now but couldnt give me an descriptive answer or as he put it "its a the kinda thing you just know"

Anyone?
"Beating the hell out of other peoples cars since 1999"
1983 Ford Thunderbird Heritage
1984 Ford Mustang GT Turbo Convertible
2015 Ford Focus SE 1.0 EcoBoost

What is a "Rolling Idle" exactly?

Reply #1 –
I would say it would be the same thing as a surging idle - the idle "hunts" up and down. Usually caused by a vacuum leak, but can also be caused by a bad sensor (MAP or TPS) or a sticky IAC valve, or if the battery has been disconnected and the idle relearn procedure not followed. My '91 did just that - I had disconnected the battery for some reason, then reconnected it and drove off. For about a month afterward every time the A/C kicked in the idle RPM would go up to about 1500 RPM. Was a real pain in the butt while sitting at a stop light in gear. I finally disconnected the battery again, started the car with the A/C off, and let it idle for about 15 minutes before turning the A/C on. Problem went away :D

It can also be caused by letting your T-Bird sit around for two years, only starting it to move it in and out of the garage while the gas in the tank gets old. New gas helps immensely :hick:
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

What is a "Rolling Idle" exactly?

Reply #2 –
From everything I read that is right on except, to be very clear, it's more of hunting UP and resettling back to set idle.  An abnormally low idle (one that drops beneath the car's set idle) or an idle that is high and stays high comes from a completely different set of problems.
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

What is a "Rolling Idle" exactly?

Reply #3 –
thanks for the explanation. my gut wasnt really set on deciding whether he meant rolling idle as a like a boggy, kinda missfiring idle or like how you explained it. what lead me off was normally you would consider that "hunting"(right?) like a vacuum leak and if thats what he meant he shouldve just said that:flame:
"Beating the hell out of other peoples cars since 1999"
1983 Ford Thunderbird Heritage
1984 Ford Mustang GT Turbo Convertible
2015 Ford Focus SE 1.0 EcoBoost

What is a "Rolling Idle" exactly?

Reply #4 –
Yeah, it struck me as strange that he couldn't explain it....?!?
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats
 

What is a "Rolling Idle" exactly?

Reply #5 –
word-a-mudalation

kinda like "wreckless driving".  seems we all should be wreck LESS.

ie-helpless = you can't help yourself so you need helpful people
or
hopeless = you have very little hope and you need hopefull advise

or even better and in the same context,,,wreckless driving
you dont wreck or cant wreck so you need help in that area as well, ie- wreckfull