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Car slowing on downhill coasting ?

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Old 09-19-2015, 10:03 PM
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Car slowing on downhill coasting ?

This just smacked me on the head today, been trying to figure it out, would like to know what could possibly be wrong with the car, or am I just stupid and everything is ok.
I thought according to physics the opposite is supposed to happen, as you see in the picture below the stretch I took approaching the bridge is a downhill,
I was doing about 120km approaching the bridge so I let go off the gas around the same spot at the edge of the picture where you see that white car, and I let the car coast...

But by the time I reached the bridge I was almost down to 100km... am I stupid or just missing something here ??
I know I got -2 camber front and -4 rear, my toe in check, slammed to the ground but is all that possibly a reason ??


 
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Old 09-19-2015, 10:41 PM
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Physics doesn't really work that way. If the grade isn't steep (gravity) enough to over power the friction of your car (stickiness of the tires, coeffient of drag,weight of the car, bearing friction, temp of the road, ambiant temp) your car will most definitely slow down. Every grade will be dependant on these factors. The grade minus your friction will only let you go so fast.
 

Last edited by ScraggleRock; 09-22-2015 at 05:53 PM.
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  #3  
Old 09-20-2015, 02:51 AM
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are you an AT or 6mt? do you put the car in neutral or leave it in gear? if you leave it in gear that will slow the car down. and like scraggle said if the grade is not too steep gravity will not overcome friction.
 
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Old 09-20-2015, 01:25 PM
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Yea I'm aware of the basic things you guys mentioned, I thought I might be missing something else... I just didn't think these things would come in play on a slope like this as you can see in the picture it's not that small, I know it's not big either...


Anyway the reason I made the post is I was actually worried about something wrong with the engine possibly, decelerating like that or something, I don't know... because I've just recently had ALL OF MY DASH LIGHTS turn on, like every possible warning light that could be on is on, event the damn battery light.
I also have issues turning the car on, it takes an extra 2 seconds to turn on from the usual time....

I'm taking it into the shop soon, so yea I just hope it's what you guys mentioned and not something more serious with my engine or transmission
 
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Old 09-21-2015, 09:12 AM
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Bad ground, faulty fuse, starter, battery not charging so alternator issue...
 
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Old 09-21-2015, 10:40 AM
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The downhill slope on the Port Mann isn't too steep in my books. Try a pain in the *** downhill like Royal Oak or anywhere in White Rock.
For me (Auto), I generally slow down too on a slope similar to that if I was sitting at 120KM/h.
 
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Old 09-22-2015, 03:02 AM
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^ yea it's not that steep i know....

I been having engine issues like I said, both in idling and throttling, when I was driving on that section, it kind of felt the engine was battling me throttling down a bit, it almost felt like the car was slightly braking.

Venom I got my starter and battery replaced few months ago, and spark plugs 3 years ago... my problems are something else, I'm gonna have to have a shop figure it out, because I don't fck with electrical, done almost everything else on my car, but the electrical I leave to the experts.
 
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Old 09-22-2015, 09:14 AM
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I concur, I can't do electrical very well. It was nice growing up with my brother around because he was a wizkid with it...picked up a few things but not my style.
 
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Old 09-22-2015, 12:05 PM
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^ I used to do complete headlight modifications for my local Nissan/Infiniti club, done dozens of them, and doing the wiring and LED's n all that ****, always made me cringe.

But yea I just immediately thought it was some kind of issue with the car because I've never felt it slow down like that before, and not that it wasn't steep enough.
I remember years ago I had a problem where one of my pads was stuck on the rotor slightly and it would make constant contact with it even when I let go of the brake, would slow the car down constantly, had to replace the pad turned out it cracked right in the middle.
And I know the only other thing that could be slowing me down would be extreme toe and camber or super sticky tires, but I know that isn't the case.
I suppose I can rest easy and chalk it up to the grade not being steep enough this time, still gotta fix my car issues though.

But yea that's what I wanted to know guys, to see if it could be anything else possibly that's out of my understanding of some of these basic things I mentioned, something I may have missed or not thought about, thanks for suggestions.
 
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Old 09-22-2015, 03:56 PM
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Nicely said Scraggle.

I too had that issue with my old engine, not sure about this new one yet.

I fixed up the grounds, I was blaming the extended crank on low compression. If it continues with this new motor who knows. I would hate life a little bit tbh.
 
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