95 S4 won't start - follow up

[taos_skier]

Hi. If you read my previous posting....

I called a friend who is a mechanic and he pointed me to the fuel rail... after the ignition is turned to on, the rail should be pressurized he said. With the ignition turned to on, when I check the valve that is like a bicycyle tire valve (schrader valve I believe), no fuel comes out... it doesn't seem to be pressurized.

I checked the fuses, they are fine and the relay for the fuel pump at least looks fine (I don't know how to check the relay)...

So it seems that my fuel pump may have just died, but I am not sure. There's gas - the tanks are almost full. I've never let the fuel go below 1/4 of a tank, but don't know about the previous owner.

Is the fuel pump internal or external to the fuel tanks? If internal, is there just one pump in the tanks, and if so, which one?

Thanks for any help.

steve

[TimRdLotus]

If it's like my 90 the pump is internal inside the tank. Just to make sure it's fuel, take some carb cleaner and spray it into the intake manifold through a vacuum line. Then try to start it. If it starts and dies, then you have a fuel problem But before you replace the pump, turn the key on and you should hear a humming sound then stop after about 4-5 seconds. That's your pump. If you can hear it, then check your fuel filter. Try a new fuel filter before you replace the pump, it's a lot easier and cheaper. It could be clogged.

If you have to remove the fuel pump, it should be at the passenger side (US) of the quarter window panel. It's a bear (very tight space) but it is very do able.

Good luck.

[taos_skier]

Thanks very much for the tips Tim! I will start with the fuel pump sound and go from there.

steve

[Paul C]

I checked the fuses, they are fine and the relay for the fuel pump at least looks fine (I don't know how to check the relay)...

Don't know if this is any future help,but the 8 relays

in that box are identical, so you could say, use

one of the AC ones and swap with the fuel pump

relay to check it out?

Relays that are the same:

1, radiator fans control

2, RPM/oil pressure tell tale

3, fuel pump

4, engine overheat tell tale

5, solenoid valve changeover

6, AC control

7, AC request

8, Starter motor

[taos_skier]

Hi Paul,

That's always good to know to check! I'm going to print that info out and put it in my owner's manual for future reference. Thanks.

steve

[tinywillyuk]

Hi Steve,

I note from the first part of the thread you hadnt located the fuel cut off inertia switch - on yours (and mine) it should be behind and under the fuel filter - rubber capped circular thing you just push the centre of.

If you have someone turn on the ignition whilst you look in the bay you will see the fuel lines vibrate a little if its working as the fuel comes up to pressure and you'll here it as well as pointed out.

If you did find it between posts I guess this is irrelevant now!

Good luck

Simon

[taos_skier]

Hi Simon,

Got it... Thanks! She's running fine now....

steve

[WayneB]

Do you wonder what poped the inertia switch in the first place? On some cars a small nudge on the back bumper will pop the inertia switch and unlock the central locking, enabling thieves easy access to the interior of your car...........

Edited July 25, 2005 by WayneB

[Paul C]

Do you wonder what poped the inertia switch in the first place? On some cars a small nudge on the back bumper will pop the inertia switch and unlock the central locking, enabling thieves easy access to the interior of your car...........

<{POST_SNAPBACK}>

Apparently, if you know where to thump the body on the M100 elan,

you trigger the fuel inertia switch which in turn opens the central locking

as a safety guard. Tip Top security there then....

[CNH]

I hit the rear wall with my knee while sitting in the boot working on the engine. That is enough to do it.