Audi q7 problem with start engine
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Audi q7 problem with start engine
Hello,
I have a problem with my Audi Q7 1st Gen, 2006 model.
The car was hit on the left/driver's side; the damage wasn’t too severe, it just bent the intercooler (it wasn’t broken).
Since then, it won’t start.
The diagnostics show that there is an issue with the fuel pump, but I can start it through the diagnostic tool.
The car cranks but doesn’t start; using a starting spray, I get it running for half a second.
The intercooler has been removed, and I’m waiting for the new one to arrive in a few days. Could this be causing the issue?
All fuses are fine, and the diagnostics don’t show any faulty sensors.
Is there any crash sensor that could be putting the car into safe mode?
I removed the bumper, intercooler, and left headlight.
The pump works through diagnostics, but as soon as the engine is cranked, it shuts off.
Does anyone have advice on what to pay attention to? Thank you in advance.
I have a problem with my Audi Q7 1st Gen, 2006 model.
The car was hit on the left/driver's side; the damage wasn’t too severe, it just bent the intercooler (it wasn’t broken).
Since then, it won’t start.
The diagnostics show that there is an issue with the fuel pump, but I can start it through the diagnostic tool.
The car cranks but doesn’t start; using a starting spray, I get it running for half a second.
The intercooler has been removed, and I’m waiting for the new one to arrive in a few days. Could this be causing the issue?
All fuses are fine, and the diagnostics don’t show any faulty sensors.
Is there any crash sensor that could be putting the car into safe mode?
I removed the bumper, intercooler, and left headlight.
The pump works through diagnostics, but as soon as the engine is cranked, it shuts off.
Does anyone have advice on what to pay attention to? Thank you in advance.
AudiWorld Senior Member
Joined: Mar 2017
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From: Fairbanks, Alaska
I don't know the technical aspects in these cars, but modern cars do have an impact sensor that trips the fuel pump to prevent fuel spills and fires in the event of a collision. IIRC, this requires a replacement of the relay. I am not sure what type of impact triggers it, though. I had a 2010 Forester that was in a collision years ago and the front airbag deployed, but it still started fine afterward. I want to say that the impact was at about 30 mph.
Last edited by -Wes-; Feb 8, 2025 at 04:41 PM.
AudiWorld Super User
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From: USA - NM
Yes, there is a fuel cut-off, so even though you categorize this as a 'minor' crash, it seems likely tripped the fuel cutoff/safety protocol, etc. It is normal to introduce exactly what year model, engine/fuel type, and mileage are on your Q7 when asking for assistance remotely.
When you say 'diagnostics', what type of scan tool was used; Audi's require you use a VAGCOM compatible scan tool that can speak VW coding, etc., although you mentioned a fault code is present. The thing about using a VAGCOM type scan tool is that it can show you all the fault codes your car has stored, not just the ones that trip a CEL, etc.
If you've got any fault codes, post up all that information up on here, as we know zip about your car except the data and details you share.
When you say 'diagnostics', what type of scan tool was used; Audi's require you use a VAGCOM compatible scan tool that can speak VW coding, etc., although you mentioned a fault code is present. The thing about using a VAGCOM type scan tool is that it can show you all the fault codes your car has stored, not just the ones that trip a CEL, etc.
If you've got any fault codes, post up all that information up on here, as we know zip about your car except the data and details you share.
Thread Starter
AudiWorld Newcomer
Joined: Feb 2025
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Likes: 1
I did it!
Thanks to everyone for the advice, I checked everything, but I'm still not 100% sure what exactly happened.
The fuel pump kept shutting off, and that confused me.
I opened the fuel tank, and I heard air entering it, creating a vacuum in the fuel system.
My assumption is that by removing the intercooler, an airlock was created, and when I turned on the pump via diagnostics, I created the vacuum.
After opening the tank and adding just 5 liters of fuel, the car started after some cranking.
It smoked quite a bit, probably because of the fuel that got on the pistons.
The intercooler should arrive tomorrow, but I believe everything will work fine after that.
Thanks again to everyone, I'll send further instructions regarding the car and the issues if they might be useful to someone.
The fuel pump kept shutting off, and that confused me.
I opened the fuel tank, and I heard air entering it, creating a vacuum in the fuel system.
My assumption is that by removing the intercooler, an airlock was created, and when I turned on the pump via diagnostics, I created the vacuum.
After opening the tank and adding just 5 liters of fuel, the car started after some cranking.
It smoked quite a bit, probably because of the fuel that got on the pistons.
The intercooler should arrive tomorrow, but I believe everything will work fine after that.
Thanks again to everyone, I'll send further instructions regarding the car and the issues if they might be useful to someone.
AudiWorld Super User
Joined: Jan 2021
Posts: 4,567
Likes: 1,456
From: USA - NM
That's great that it started.
How much fuel was in the tanks/indicated on fuel gauge? The Q7 uses a split fuel tank design to keep center gravity low an distribute weight evenly, so there are two fuel pickups...one for each tank. If the low pressure lift pump in the fuel tank (one side only) is pulling air that would seem to indicate either a distinct lack of fuel in the tanks OR that a fuel pickup line is broken loose or damaged, which is allowing it to siphon air.
How much fuel was in the tanks/indicated on fuel gauge? The Q7 uses a split fuel tank design to keep center gravity low an distribute weight evenly, so there are two fuel pickups...one for each tank. If the low pressure lift pump in the fuel tank (one side only) is pulling air that would seem to indicate either a distinct lack of fuel in the tanks OR that a fuel pickup line is broken loose or damaged, which is allowing it to siphon air.
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