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Discussion Starter · #1 · (Edited)
2000 db7 vantage running on left 6 cylinders only,, right side of engine not firing, checked all fuses relays etc.. 1st try was fuel pressure at fuel rail but have 65lbs per repair manual at the fuel rail.. This is a problem that seemed to have been solved by disconnecting the negative on the battery but now does not solve it. any thoughts or suggestions greatly appreciated by the 1st time poster..

Ok , update! Purchased a code scan device, ( pretty easy to use by the way) and guess what ,, po300 thru po306 , multiple engine cylinder misfire, really? I kew that already but it also said p0004 thru p0006 all related to fuel delivery! How can that be. I checked fuel pressure at the rail on the right side and had 65 psi,, well guess what, I didn't check the fuel rail pressure on the left (driver side) of the engine turns out the fuel rails are on opposite sides of the cylinders they are supplying! WTF! I guess it made sense to the designer,, would never have discovered it without the shop manual and code scan device,,, tested fuel pressure at the wheel well filter and still no pressure,, checked fuses again and I feel I am left with nothing but the secondary fuel pump which I am sure is a bear to remove from the fuel tank,,

Anyone have any thoughts or suggestions,, I'm sure that is all it can be at his point,, any input is greatly appreciated
 

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Discussion Starter · #8 ·
Fixed it

Sorry I don't check this very often, yes it is fixed but it turned out not to be fuel pumps but the electrical connection that supplied power to the left pump. A symptom of this was it would work fine , stop working, then work again mysteriously. It had burnt at the connector and did not pop the fuse strangely. Finally it completely failed. I only discovered it after buying new pumps and installing them which did not fix the problem! Talk about frustration! Here is a tip for anyone that encounters the problem. you can access these electrical plugs in the wire loom by tracing them backwards from the pump connection. They should be encased in a foam like tape material.Run a wire from the plug straight to the battery which allows you to hear the pump running or not running. That way you know the pump has failed before you spend the time to remove the tank which is a BIG project. (if you disconnect one of the fuel lines at a filter and attach a rubber hose this is a slick and easy way to empty the fuel out of the tank if you do have to remove the tank)

Story gets better, after I solved the wire issue I drove the car for about a week and it did the same thing. Of course I did what every home mechanic should do and that is check the last things you worked on first. All good! Ran the wire, heard the pumps running, WTF! Long story short one of the hoses that comes off the top of the pump came off which i discovered after removing the tank the second time! My bad luck but the lesson is patience and persistence pays off. These cars are just machines albeit beautiful amazing ones but they can be fixed. A shop manual is a must by the way and these forums are greatly appreciated. If anyone has any questions or other input feel free. I'll check back more often!
 

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Discussion Starter · #10 ·
Sadly paid to much for the Aston fuel pumps,, I've learned that lesson though. Had a window regulator fail and called Aston. They wanted $1100! I found it on another site for 40 pounds English with shipping from England. So, lesson learned.
 

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Discussion Starter · #15 ·
sounds like it could be fuel delivery issue which is common and manifests itself in half the engine firing, (one side cold, one side hot) each side of the engine has separate fuel pumps and delivery lines . Both pumps are unfortunately housed in the fuel tank!!!!You can Test fuel pressure at the rail by removing the cover (looks like a tire stem cover) and pressing with a golf tee or anything but that will press it in. It will squirt out if you have pressure or nothing if you have no fuel pressure...Remember the fuel rails that feed the right are on the left and vise versa. That just confirms you have a fuel delivery problem to one side of the engine which could be a bad pump, a bad wire , fuel filter , failed hose in the tank or any number of things.....Don't run the car much in this condition as it will destroy the cats.. If you do once you fix it , it will smoke like hell until it clears itself..

Been a while since the problem so I'm doing this from memory..

Before you start taking a lot of stuff apart you can test the pumps and hear them run. (Of course the car is turned OFF) I did it like this! as always I unhooked the battery first!!!! I have a vantage volante so I'm not sure about the coupe setup but if you pull the boot liner out you can see the fuel pump wiring coming out of the top of the fuel tank.. Follow it back in the wiring loom to the right (passenger side of the trunk) Both pumps are wired separately and have separate hot and ground lines that merge into plugs that are wrapped In a foam like material. I took it apart and ran a straight wire to the battery that allowed me to hear each pump running. That will tell you if a pump is bad or if it is a problem like a fuse or a burnt wire (in my case)

Taking apart the tank to get to the pumps is a whole different animal but can be done with persistence, patience and care in your home garage with basic tools.. If you don't hear both pumps run by straight wiring them to the battery from the plug then one is bad. You have to test them separately.

Feel free to contact me if you have questions or discover you need pumps. I have 2 good ones as I replaced both mine last time when I really didn't need to.. Good luck!
 

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Discussion Starter · #17 ·
Sounds exactly like me.. A manual , basic tools and alot of persistence and patience..

Your dont actually have to take the tank all the way out.. I just slid it out enough to access the pumps.. Careful with the plastic vapor re-circ on top.. I think its blue plastic or something.. you can brake the hose attachments if you are not super careful removing them...

toughest part is to slide the tank back you have to disconnect the fuel line under the tank.. thats a bear.. Dont do anything dumb like remove the rear axle as I've heard people do.. You can reach those clips with needle nose as I recall and pull them off then the hose just pops out.. They are tough to reach and a real SOB to get back on but just be persistent..

I wouldnt think 20 miles would be a problem.. I drove mine more than that because the problem would come and go intermittently.. It will smoke some when you start it back up but it should clear itself up

Best of luck ,, feel free to contact me if need be..
 
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