RPMs at idle

[rwyma]

Have a 2013 RT and when I start it, RPMs jump between 1300-1400 continuously. Is that normal? Just replaced spark plugs and wires.

[ARtraveler]

Yes, that is the range for idle. The 998 twins are high rpm machines. They like to be shifted and kept in the 5000-5500 range and higher.

In slow traffic, like 30 mph rush hour...you may not even shift out of first gear. We rented a Spyder in Maui HI, back in the day. Did the Hana Highway. Twisties, hairpin curves, etc. Never got out of first gear for the 100 mile or so round trip.

You will most likely not get to fifth gear until you reach 55 mph or higher...if you keep the engine "happy" in the 5000-5500 range.

[rwyma]

Thanks, I do know the 998 is high rev and should never let it get below 4500 when driving. I was just curious if the RPMs bounce around when at idle.

[DGoebel]

Mine does the same.

[Nobodyjj]

2013 STS, revs move up and down in the range at idle.

[Bfromla]

1300~1700 is fine for 998 the SE5 will start movement 1700+. Mine stalls if goes to 1100 or less apparently related to getting too much gas one time that screwed up the evap valve & canister. Very well may have led to my current starting issue found someone with trailer getting to tow to shop Monday or Tuesday

[davev1pa]

My 2012 RTL SE5 3500 miles is in the shop for idle at 1200-1600 which inhibits smooth acceleration and a bit of shudder in the tranny when it's low rpm.loud and annoying clatter ....then Zoom...it takes off. Code P1171 lean #1 check fuel system/injector. Replaced the vacuum lines off the MAP ..they were fine..checked o2 sensor wiring. No evidence of pug wire issue. Ran a bunch of Techron fuel injector and Techron fuel system cleaner plus some Seafoam thru it for 100 miles. Took it to the dealer. They checked the throttle body mounts-they're ok..they're a perplexed as I am. This thing runs awesome down the road . 29 mpg . No hesitation in higher rpms. Thoughts?

UPDATE: Took to dealer. They re-did vacu hoses off MAP sensor. Did the spark plugs. STILL had erratic idle 1200-1600 . Scratched their heads called BRP. Solution: reflashed the ECU with latest software from BRP. Works great now. Thanks for everyones help.

[safecracker]

Thank you for letting us know what the fix was. Bruce

[davev1pa]

Well my idle issue was not Vacuum hoses, spark plugs or evap hoses. They reflashed the ECU with a download from BRP on the BUDDS and that fixed it. And $506 dollars Yeah that hurt but it read P1171 for lean cylinder #1 so we went with mechanical stuff 1st...dang computers!!!

[johnc1921]

My idle jumps the same: 1300-1400. Weird, but it runs great. I just try to keep it above 4000RPM. Haven't had it in 5th gear yet. 4th gear at 70mph runs great. I'm glad I have cruise control

[davev1pa]

I think 1300-1400 is just normal but if the tranny shudders into gear at low RPMs it's not ok. My idle was 1200-1600 and the most god awful transition from a stop and not until 10-15 mph did I get a smooth acceleration.. A re boot of the ecu was the fix for me after many wasted hours and consternation.