[Coachkwj]

Just got a 2008 Frontier with V6 and absolutely love it!
However I do have one concern. No matter what the temperature, when I start it the engine revs to 2000 rpm for a few seconds then drops down to 1500 for about 30 seconds then drops down to normal. Is this high rpm at startup doing the engine harm? I took it to the dealer as it is still under warranty and they assured me it is normal and will do no harm. I'm not so sure. Any thoughts?

 

[quadracer200]

Nothing to worry about....they all do that.

 

[colin123]

warm up cycle, one of the many benefits of modern fuel injection

 

[davidapplewhite]

it seems to me like it promotes dry starts. Just my 2 cents, I don't like it.

 

[HKYStormFront]

^^^ yea i agree but it's for emissions sake... yay tree huggers :thatswck:

 

[Mathster]

gotta get those cats up to temperature as fast as possible.
fuel economy doesn't matter as long as the NOx is right.

 

[HKYStormFront]

^^ yup that's it :comphead:

 

[bwarren228]

Every vehicle made does this except for hybrids. You haven't noticed?? lol

 

[Mathster]

Every vehicle made does this except for hybrids. You haven't noticed?? lol

no.
Not to the extent my gen 2 does it. my gen 2 does it EVERYTIME. My gen 1 does it on a cold engine and maybe 1200 rpm in the summer, maybe 1700 - 2000 rpms in the winter.
My 71 Chevy with a manual choke, didn't high idle at all.

 

[quadracer200]

Well your '71 chevy didn't high idle because it had a caburetor instead of modern fuel injection.... Modern vehicles have an ECU that tells the engine to idle up on a cold start. Ever notice your new frontier never has a problem starting? Modern electronics my friend. I don't know for sure if it's really to warm the cats or not, but it definitely helps the engine reach operating temp better.

 

[HKYStormFront]

yea cats operate at peak efficiency when heated up (some cars even come with electrically heated 02 sensors to pass emissions because without them they will fail during cold startup). to do this they raise the idle up so that the engine warms up faster if idling. i believe the fuel mixture is also a little richer too.

 

[rcr_kx250f]

The truck also does this in case you have crappy fuel in there. I don't think you would be very happy if you started your truck up and it barely ran for a minute until the cylinders heat up.
As far as dry starts go, there's a ton of oil in the heads at all times, and cranking oil pressure is almost 60 psi, which keeps the cylinder walls nice and wet.

 

[Coachkwj]

Thanks for the replies.

Thanks to everyone who posted. I was worried about the high RPM dry starts but it appears it is not an issue.
My wife has an '09 Murano V6 and it starts cold at around 1500 rpm which got me to wondering. Hers is a 3.5L though so maybe there is a difference from my 4.0L.

 

[eckemoff]

Basically, due to this, making short trips SUCKS on the frontier as far as MPG.... I make a lot of trips on our ranch and it literally kills overall MPG.

 

[chainsaw]

Yes this is normal as stated before, nothing to worry about. Ever work around a gen set? They got straight to running speed the second you start them. The oil pressure is up in milli seconds, much faster then the gauge says.