Fuel tank/pump issues. PLEASE, PLEASE, yes I am pleading.
10-24-2008, 04:56 PM
#1
AudiWorld Senior Member
Thread Starter
Join Date: Aug 2008
Posts: 657
Likes: 0
Received 0 Likes
on
0 Posts
Fuel tank/pump issues. PLEASE, PLEASE, yes I am pleading.
All o-rings replaced, fuel pump replaced and the car will not drive after 7+ gallons are used (after tank is full)
There has to be a procedure to the fuel pump.
Does anybody have any clues or ideas.
It all started with the no start on first crank problem then the car died so fuel pump was replaced then it cranks fine but after 7+ gallons are used the car acts like if it's on empty.
I don't know what else to try at tis point.
There has to be a procedure to the fuel pump.
Does anybody have any clues or ideas.
It all started with the no start on first crank problem then the car died so fuel pump was replaced then it cranks fine but after 7+ gallons are used the car acts like if it's on empty.
I don't know what else to try at tis point.
10-24-2008, 06:56 PM
#2
AudiWorld Super User
Join Date: Oct 2006
Posts: 2,468
Likes: 0
Received 0 Likes
on
0 Posts
Bypass the fuel pump relay and give the pump direct power.
Listen for the buzz.
Crank the engine.
If no start, then verify fuel pressure.
If pressure low, check for plugs in the line (i.e. fuel filter clogged).
Crank the engine.
If no start, then verify fuel pressure.
If pressure low, check for plugs in the line (i.e. fuel filter clogged).
10-24-2008, 08:26 PM
#3
AudiWorld Super User
Join Date: Sep 2005
Posts: 2,666
Likes: 0
Received 0 Likes
on
0 Posts
in my early ownership I had a pump failure that was caused by the
failure of the evap valve.
After replacing the pump the car would run sluggishly until the tank dropped to 3/4 then all would come right.
Turned out the evap was causing the car to run rich until there was enough air in the tank to allow the vacum to reach a level that all would function ok.
Replaced the valve and all was ok.
During replacement of the pump there were issues like yours that were to do with placement of pickup hoses inside the tank-took some time to resolve and at least attempts.
Suggest that you remove pump and check placement of pick up hoses then refit exactly as procedure in manuals
After replacing the pump the car would run sluggishly until the tank dropped to 3/4 then all would come right.
Turned out the evap was causing the car to run rich until there was enough air in the tank to allow the vacum to reach a level that all would function ok.
Replaced the valve and all was ok.
During replacement of the pump there were issues like yours that were to do with placement of pickup hoses inside the tank-took some time to resolve and at least attempts.
Suggest that you remove pump and check placement of pick up hoses then refit exactly as procedure in manuals
10-25-2008, 03:59 AM
#4
AudiWorld Super User
If it's not the fuel pump
It could be the N80 purge valve. The only reason I say this is that my wife's A4 had problems starting after filling the tank. It was the N80 purge valve which caused some type of vapor lock on the system. It purges the tank through the charchoal canister.
I believe on the pre facelift car the valve is located under the plastic piece just aft of the air box.
Do you have the Bently? Did you follow the procedure for the fuel pump replacement? Did you follow the procedure if it doesn't pump after going below half or 1/4 tank?
If it's after 7 gallons....I can't say I've heard that one before.
I believe on the pre facelift car the valve is located under the plastic piece just aft of the air box.
Do you have the Bently? Did you follow the procedure for the fuel pump replacement? Did you follow the procedure if it doesn't pump after going below half or 1/4 tank?
If it's after 7 gallons....I can't say I've heard that one before.
10-25-2008, 07:14 AM
#5
AudiWorld Senior Member
Thread Starter
Join Date: Aug 2008
Posts: 657
Likes: 0
Received 0 Likes
on
0 Posts
I am going to disassemble the fuel pump and reassemble the fuel pump according to the Bentley...
I will follow each step to the letter.
After that I will check the evap valve according to Always Overcharged and check the N80 purge valve according to PaulW.
My reasoning is that I really believe that the fuel pump has not been installed correctly.
Thank you guys very much and I will keep you informed.
After that I will check the evap valve according to Always Overcharged and check the N80 purge valve according to PaulW.
My reasoning is that I really believe that the fuel pump has not been installed correctly.
Thank you guys very much and I will keep you informed.
10-25-2008, 08:15 AM
#6
AudiWorld Member
Join Date: Aug 2006
Posts: 113
Likes: 0
Received 0 Likes
on
0 Posts
This is the same thing that happened to me.
You are correct to disassemble and do over again. The kicker is getting that little pickup tube on the side of the fuel pump seated correctly
Trending Topics
10-25-2008, 03:03 PM
#8
AudiWorld Super User
Join Date: Sep 2005
Posts: 2,666
Likes: 0
Received 0 Likes
on
0 Posts
Evap -purge valve are the same thing -located near air box under cover
<center><img src="http://www.autohausaz.com/secure/PartImages/0280142308.jpg"></center><p>
search will show pics
search will show pics