lets discuss Crank Position Sensors for a moment
#32
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At 24s cold start, the voltmeter reads 11v, you need a new battery. I can hear it cranks slower than normal too even when cold. Since you get 14v after the engine starts, I think your alternator is most likely fine but there are tests to verufy that.
Now hot start, you turned the key really quickly but I think I saw the same 11v right before you crank it. That means your battery is not charging properly during drive. Corrosion may contrbute but when the engine is not running, the voltmeter will show the full battery voltage even with corrosion. So I think your battery is weak.
i expect a full powerful hot start if you jump from the engine bay. If yes, do what Speed suggested to jump start from the frunk to eliminate the cables. You could have a parasitic draw that's draining your battery over night.
Now hot start, you turned the key really quickly but I think I saw the same 11v right before you crank it. That means your battery is not charging properly during drive. Corrosion may contrbute but when the engine is not running, the voltmeter will show the full battery voltage even with corrosion. So I think your battery is weak.
i expect a full powerful hot start if you jump from the engine bay. If yes, do what Speed suggested to jump start from the frunk to eliminate the cables. You could have a parasitic draw that's draining your battery over night.
#34
#35
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Maybe someone else can weigh in on whether they have ever seen this with P-cars, but I know some other makes have experienced this behavior when the starter heats up due to proximity to the motor, and the starter tolerances are so close that the resulting expansion causes the starter to bind It will not show up on a bench test because the starter is cold at the time.
#36
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Maybe someone else can weigh in on whether they have ever seen this with P-cars, but I know some other makes have experienced this behavior when the starter heats up due to proximity to the motor, and the starter tolerances are so close that the resulting expansion causes the starter to bind It will not show up on a bench test because the starter is cold at the time.
I found the + connection up under the transmission, it shows promise of being an issue. But will take to long to try to remove.
So
Tomorrow I will go buy what I need to bypass this cable.
If the problem persists after this, I will remove the starter again and find a shop that can heat it to 270* before they test it. And then I think the problem will show up.
#37
Captain Obvious
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I had this happen on my old Trans Am, during changing of the starter, I was too lazy to pu the starter heat shield back on and had the same exact issues that you have now. Ths starter would heat up from the aftermarket headers and do exactly what you have in the video. Therefore, I'm agreeing that your issue is probably a starter that acts up when it's heat soaked.
#38
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after watching your video i think my car had kinda similar attitude 2 years ago, so, i simply went to autozone and bought biggest battery i could fit into frunk, you have to undo a bolt in the stock battery holder to fit bigger longer unit in there.
it is heavier than a stock one, indeed, and it sux to haul more dead weight in the sports car but after that i never had issues with slow cranks and car can sit in a garage way longer now with no issues.
if you have good pro grade multimeter you can try to measure actual voltage drop at the battery terminals during fast cranks and during slow cranks, you will need an assistant for that.
you can always use an external battery and when car is shut off with key off apply voltage to starter directly when car is hot and off on neutral gear to check if you get mechanical issue with some bearings or starter itself.
it is heavier than a stock one, indeed, and it sux to haul more dead weight in the sports car but after that i never had issues with slow cranks and car can sit in a garage way longer now with no issues.
if you have good pro grade multimeter you can try to measure actual voltage drop at the battery terminals during fast cranks and during slow cranks, you will need an assistant for that.
you can always use an external battery and when car is shut off with key off apply voltage to starter directly when car is hot and off on neutral gear to check if you get mechanical issue with some bearings or starter itself.
#39
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I had this happen on my old Trans Am, during changing of the starter, I was too lazy to pu the starter heat shield back on and had the same exact issues that you have now. Ths starter would heat up from the aftermarket headers and do exactly what you have in the video. Therefore, I'm agreeing that your issue is probably a starter that acts up when it's heat soaked.
#41
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I have thought about a higher crank amp battery, but to me that is a band aid and not really fixing the problem. I feel eventually your problem will resurface with no where else for you to go as what ever the true issue is continues to get worse.
after watching your video i think my car had kinda similar attitude 2 years ago, so, i simply went to autozone and bought biggest battery i could fit into frunk, you have to undo a bolt in the stock battery holder to fit bigger longer unit in there.
it is heavier than a stock one, indeed, and it sux to haul more dead weight in the sports car but after that i never had issues with slow cranks and car can sit in a garage way longer now with no issues.
if you have good pro grade multimeter you can try to measure actual voltage drop at the battery terminals during fast cranks and during slow cranks, you will need an assistant for that.
you can always use an external battery and when car is shut off with key off apply voltage to starter directly when car is hot and off on neutral gear to check if you get mechanical issue with some bearings or starter itself.
it is heavier than a stock one, indeed, and it sux to haul more dead weight in the sports car but after that i never had issues with slow cranks and car can sit in a garage way longer now with no issues.
if you have good pro grade multimeter you can try to measure actual voltage drop at the battery terminals during fast cranks and during slow cranks, you will need an assistant for that.
you can always use an external battery and when car is shut off with key off apply voltage to starter directly when car is hot and off on neutral gear to check if you get mechanical issue with some bearings or starter itself.
#42
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Am having very same symptoms on my '99 996 C2 - at a DE this weekend. Tried jumping from my Highlander and from a portable battery pack at various moments and it didn't really help much - was jumping at the battery in the frunk - didn't occur to me to try the engine jump point - doh. Didn't have my DVM handy but will make sure I bring it next time.
I have a Durametric - any real time data I should try to capture during cranking ?
Anyways - subscribed - looking forward to hear when you do solve the issue.
I have a Durametric - any real time data I should try to capture during cranking ?
Anyways - subscribed - looking forward to hear when you do solve the issue.
#43
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Its either vapor lock or starter. I did the test with running a jumper cable from the Battery to the jump point in the rear of the car. Same exact situation. Maybe to night I will do it again and use a jump battery in the back.
#45
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