Crank sensor problem possibly

2011 AUDI A5
120,000 MILES • 2.0L • 4 CYL • TURBO • 4WD • AUTOMATIC
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MICHAEL5RUEDA
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So I had this mild off road incident a few weeks back, and I had to get my vehicle towed back home as it wouldn’t start because of a few sensors that got damaged. I first tried starting it and it wouldn’t turn over or do anything so I changed out a sensor that was located in the back of the battery as it had blown out from the curtain air bag that deployed. Then the car cranked and turned over but shuts off right away. My question is if possibly the crankshaft sensor got damaged or like a short although the front end and engine didn’t get damaged at all (not a single scratch) just mild damage on passenger side rocker panel and suspension damage. There’s not check engine light on the dashboard or anything either so I’m not sure what could be the issue. I’m going to check out the crank sensor to see if it has any damage or try ordering a new one to see any results. If you could please help and trigger what could be the issue not to remain on when I crank it i would greatly appreciate it very sincerely.
Oct 16, 2020 at 1:39 AM
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KASEKENNY
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If the engine starts then shuts off the crank sensor is fine. The PCM will not fire the engine if the crank sensor is damaged because it will not know when to fire the plugs and injectors as the crank is the "timing" sensor. The fact that the airbags deployed and the start and stall tells me that we are in a security event. Does the theft light come on then go off when you turn the key on or does it stay on or flash when the key is on?

When airbags go off, a lot of times we have damage to a crash sensor which is what triggered the airbag. So we need to scan for codes and go from there. Even though the check engine light is not on we may still have some codes.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Are there any other warning lights on?
Oct 16, 2020 at 8:36 AM
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MICHAEL5RUEDA
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No there isn’t any warning lights on the dash other then a suspension light.
Oct 19, 2020 at 1:01 PM
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KASEKENNY
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Okay. Have you actually checked for codes? If not, we will want to do that and see what is there.

Also, does the engine start and stall every time you crank the engine? Can you get a video of what it does when you start it?
Oct 20, 2020 at 7:42 PM
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MICHAEL5RUEDA
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I haven’t been able to get a hold of a odb scanner yet. hopefully this week but I uploaded a short clip of what it does when I start it up so you can take a look of what it actually does. By the way I appreciate your time to respond and help out! Blessings.
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Oct 20, 2020 at 10:32 PM
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MICHAEL5RUEDA
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The whistle you hear in the background is from a loose hose on the passenger button side where it directs into the inner cooler. I need to order a new one as that one is loose from breaking off from the inner cooler.
Oct 20, 2020 at 10:35 PM
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KASEKENNY
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Okay. Code check is great and then we need to start with the basics. Start with ruling out the fuel pressure.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Then does the engine start and stall like this every time you try to start it? Of does it only do this once and then just crank?
Oct 21, 2020 at 6:57 PM
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MICHAEL5RUEDA
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I tried checking for codes but didn’t throw any at all and yeah every time I try starting it it does that it cranks over then after like 2-3 seconds of feeling weak like startles then turns off. I have a stock hose on the front left bottom side that goes right into the Inter cooler detached from it as air escapes as you can hear in that video and I’ve seen symptoms of a bad or broken hose to Inter cooler to make the vehicle lose power or not start as you can see in the pic the circled part is what’s detached from the intercooler and I don't know if that could maybe be the problem. Also the I’ve noticed that on the MMI screen it says battery weak I’ve read that symptoms of weak battery could cause to struggle to turn on too but way before that sign every popped up of the battery being weak the car was still doing the same I’ll need to check voltage storage in the battery as well see if it does anything different.
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Oct 22, 2020 at 1:34 AM
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KASEKENNY
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I am sorry. I didn't pick up on that when you said that earlier. If you have a leak in the intercooler hose then that will allow air to escape and not enter the engine. This will definitely cause this issue. Since you have this issue and have that broken, we need to fix that first and then see if this is still an issue.
Oct 22, 2020 at 3:04 PM