10-23-2020, 05:35 PM | #1 |
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8ZHP cold start & engine jerky?
I am noticing that when starting up my car in the morning or a cold start, while still in park mode, the engine or whatever the car feels like a tiny jerk/shift motion. It's a brand new F32 stock car and no engine mods, etc. Maybe as a result of engine piston/block working harder upon a cold start being that it's an automatic.. but I do not ever recall this situation when I had my F30 6-speed manual. It's always in neutral gear anyways during a cold start.
Does anyone share similar experience what i am going through, or it is normal operations of the 8ZHP. |
10-23-2020, 10:23 PM | #2 | |
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10-23-2020, 11:37 PM | #3 |
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Yeah I probably will take it in, because no idea why it does that. The engine jerky/movement only last for like a quick second, then engine idles like normal and I drive off after few seconds of the cold start.
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10-24-2020, 01:45 AM | #4 |
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This is normal. I too get that sudden/random jolt. I feel it on my car and have felt it on new cars as well.
The worst car that had it was my Alfa Romeo Giulia where it would constantly rock the car back and forth when cold. You can try the dealership but they won't find codes for it and you'll more than likely get hit with the "cannot replicate" diagnosis.
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10-24-2020, 03:50 AM | #5 |
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+1 to the "cannot replicate" diagnosis or the "it's normal".
Dealer told me it's normal since the car is priming up. |
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10-24-2020, 09:10 AM | #6 | |
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Jolt is a better word to describe the situation as well. Figured it was kind of normal, I don't get this during car temperature gauge when it is in operational 195F-220F degree range. |
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10-24-2020, 09:13 AM | #7 |
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10-24-2020, 09:46 AM | #8 |
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They run these things SUPER lean for efficiency, so it is normal during the idling/warmup phase. You might get a bit of a stutter as well when you first take off when cold.
Once engine warms a bit, you should have none of this. |
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10-24-2020, 10:01 AM | #9 |
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At what RPM does this happen? At what temperature? When cold the engine will stay at a higher RPM than normal when started for faster warm up, which can cause some jerkiness when you put it in drive. I'd chalk it up to cold weather if I knew your location, but 'NA' isn't exactly specific.
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10-24-2020, 11:48 PM | #10 |
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i have this on cold start as well, if you warm the car up it goes away.
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learntocode53.50 |
10-25-2020, 10:22 PM | #11 |
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Above comments were pretty spot on. Today, almost noon time I went out for some errands, and RPM was at/around 1,100 with outside temps being 71F degrees. First start up of my car didn't have the jerky motion, or engine jolt.
My early morning commute to work during the week and cold weather seems to be root cause then on a cold start. I will take into account the RPM and outside temps. Thanks everyone for their input. |
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