Slight 'Stumble' at 4500 RPM
#1
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Slight 'Stumble' at 4500 RPM
Been driving my new (475 mile) 2014 modestly and shifting around 3000 to 3500 RPM, ran up to 4000 RPM a few times with no problem. Today I ran her up to 4500 RPM in 3rd gear and noticed an ever so slight hesitation about 4200 - 4300 RPM or so. Nothing major, but I could feel it, happened both times I tried it. Anyone else notice this? Cant' wait to hammer it..but I will wait for the first 1000 miles.
#2
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Been driving my new (475 mile) 2014 modestly and shifting around 3000 to 3500 RPM, ran up to 4000 RPM a few times with no problem. Today I ran her up to 4500 RPM in 3rd gear and noticed an ever so slight hesitation about 4200 - 4300 RPM or so. Nothing major, but I could feel it, happened both times I tried it. Anyone else notice this? Cant' wait to hammer it..but I will wait for the first 1000 miles.
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Been driving my new (475 mile) 2014 modestly and shifting around 3000 to 3500 RPM, ran up to 4000 RPM a few times with no problem. Today I ran her up to 4500 RPM in 3rd gear and noticed an ever so slight hesitation about 4200 - 4300 RPM or so. Nothing major, but I could feel it, happened both times I tried it. Anyone else notice this? Cant' wait to hammer it..but I will wait for the first 1000 miles.
Yeah I know what your talking about, I'm guessing its the VVT. If I haven't been driving for 10-20 miles and/or the motor is already warm, my rpms climb rather sloppy. Seems to be smooth until I hit 4k+ rpms. Other times its like butter. Not really sure what to think of it and taking it to my dealer would be pointless as half the folks there are tards.
I recommend both of you make an appointment with your dealers to get them checked out. Then, PM me with your VIN, dealer, full name, mileage, and best daytime number so I can escalate this to the customer service manager of your areas.
Deysha
#4
Shelby GT350 Member
Quickly looked through a couple dyno charts, there looks to be a slope change around the 4500 mark, probably something to do with variable timing? If you're holding the engine at 4500 RPM or so, I would guess you'd feel this, but if you pass through that point and keep revving, doubt you'd feel it. But like Deysha says, might be worth stopping by the dealer for a check
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Quickly looked through a couple dyno charts, there looks to be a slope change around the 4500 mark, probably something to do with variable timing? If you're holding the engine at 4500 RPM or so, I would guess you'd feel this, but if you pass through that point and keep revving, doubt you'd feel it. But like Deysha says, might be worth stopping by the dealer for a check
#6
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Quickly looked through a couple dyno charts, there looks to be a slope change around the 4500 mark, probably something to do with variable timing? If you're holding the engine at 4500 RPM or so, I would guess you'd feel this, but if you pass through that point and keep revving, doubt you'd feel it. But like Deysha says, might be worth stopping by the dealer for a check
Deysha
#8
Shelby GT350 Member
Anyone do data logging to see what is going on? That was always the first thing I would do in my previous car... log timing, fueling, MAF readings, knock sensors, etc. There look to be a couple good logging programs for iphones (with bluetooth OBDII connectors too)... Incredibly valuable tool.
#10
Shelby GT350 Member
Did you take it out for a ride with someone at the dealership? A mechanic preferably?
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