Cold Starting - RPMs rev high
11-02-2010, 08:35 AM
#1
Administrator
Thread Starter
Join Date: Oct 2002
Location: ɯooɹpǝq ɹnoʎ
Posts: 13,943
Likes: 0
Received 0 Likes
on
0 Posts
Vehicle: ǝdnoɔ sısǝuǝƃ
Cold Starting - RPMs rev high
I'm new to turbo setups. I've got a new Genesis Coupe 2.0T.
When I refer to a cold start, I don't mean environmental temperatures. I keep my car garaged and it's usually 60-75º in there. From a cold start - meaning hasn't been started in 12+ hours - the RPMs will jump to 1,000 (normal) and steadily climb for 3-5 seconds until getting up to 2,000 or as high as 2,500, then drop back down to around 1,200 before resting just under 1,000.
This is fairly consistent, and I know it's been doing it for several weeks. I don't know if it was doing this BEFORE my first oil change (3,000 miles) or immediately after. I'm at 6,200 miles right now and I'm about to change the oil. I was running 5w20 but will be switching to 5w30, Running Mobil 1 Full Synth & OEM filter. Does the oil viscosity have anything to do with this? Is this normal?
When I refer to a cold start, I don't mean environmental temperatures. I keep my car garaged and it's usually 60-75º in there. From a cold start - meaning hasn't been started in 12+ hours - the RPMs will jump to 1,000 (normal) and steadily climb for 3-5 seconds until getting up to 2,000 or as high as 2,500, then drop back down to around 1,200 before resting just under 1,000.
This is fairly consistent, and I know it's been doing it for several weeks. I don't know if it was doing this BEFORE my first oil change (3,000 miles) or immediately after. I'm at 6,200 miles right now and I'm about to change the oil. I was running 5w20 but will be switching to 5w30, Running Mobil 1 Full Synth & OEM filter. Does the oil viscosity have anything to do with this? Is this normal?
11-02-2010, 10:49 AM
#3
Administrator
Thread Starter
Join Date: Oct 2002
Location: ɯooɹpǝq ɹnoʎ
Posts: 13,943
Likes: 0
Received 0 Likes
on
0 Posts
Vehicle: ǝdnoɔ sısǝuǝƃ
Sorry, made a mistake. I'm running 5w20, switching to 5w30 next time. Owner's Manual suggests 5w20, 5w30, or 5w40. Oil Cap says 5w20 on it. That wasn't the focus of my question, just wondering if it was contributing to RPMs at all.
11-02-2010, 11:52 AM
#4
Senior Member
Join Date: Sep 2009
Location: Denver, CO
Posts: 576
Likes: 0
Received 0 Likes
on
0 Posts
Vehicle: 2003/Hyundai/Tiburon
When a car's ECU is in 'cold-start' mode that is referring to the temp of the coolant. If the car sits for 12hrs then the coolant will be completely cooled off and trigger 'cold-start' mode. Its perfectly normal as long as once the coolant warms up the idle goes back down to where it should be stock. 1000 RPM with a warmed up engine and A/C off sounds a little high to me.
11-02-2010, 12:38 PM
#5
Administrator
Thread Starter
Join Date: Oct 2002
Location: ɯooɹpǝq ɹnoʎ
Posts: 13,943
Likes: 0
Received 0 Likes
on
0 Posts
Vehicle: ǝdnoɔ sısǝuǝƃ
I don't know what the actual idle point is, haven't really paid attention other than glancing at it. I would suspect it's around 800 rpm, but it probably takes it 20-30 seconds from startup to settle at that point. I realize that it hovering slightly above 1,000rpm is fine until it warms up. Maybe I'll post a video later to help show what I'm talking about. Some times it will spike at 2,000 rpms, rarely as high as 2500.
11-02-2010, 04:19 PM
#6
Senior Member
Join Date: Mar 2006
Location: tacos
Posts: 9,533
Likes: 0
Received 0 Likes
on
0 Posts
Vehicle: 2000 Elantra
and it usually takes a few moments for your car to warm up to the point that the thermostat opens
it raises it to get the motor nice and warm, cuz a warm engine is a clean burning engine
it raises it to get the motor nice and warm, cuz a warm engine is a clean burning engine
