Advice Please

[mick rowe]

I have a 2002 996 turbo 82000 miles
on start up on sunday i noticed a sqeal coming from under bonnet on inspection i have traced this to the fuel tank so i guess something wrong in there could this be a problem with the fuel pump being on its way out or could it be something else
i have tried different things like removed fuel filler cap ran car low on fuel then filled it up and it is still the same
the car starts runs well and have no loss of power any idea what this could be
i have spoken to porsche dealer and they have listened to the noise and think probably fuel pump but say they have not come across it before and sell very few fuel pumps
i dont really want to spend nearly £500.00 on pump alone if it may be something else
any help and advice on this would be greatly appreciated
this is the first problem i have had with the car for a long time after a few initial problems when i first bought her 5 years ago
kind regards Mick

 

[924nutter]

You have a fuel tank and a pump. Fuel tanks themsleves have no moving parts, ergo it is the pump in my humble opinion, unless it is the cd changer, but the sound would be coming from further forward. It is not immediately appreciated that the Turbo has a saddle type of fuel tank becuase of the front diff, and according to my Porsche Appreticed indie, if the fuel level is allowed to go too low, the suction side of the pump can draw air when going up a bit of an incline; generally submerged fuel pumps tend to be of the roller type with the fuel flowing through the the pump, over the commutator and out, and acting as a lubricant, so no fuel or an aerated flow could lead to pump damage, and unless you have owned the car form new there is no guarantee that a previous owner has not let this happen. A squeak or squeal means the pump will be making more effort to turn so you might be able to see how much current it is drawing, but unfortunately I can't tell you what it shoud be. There is not much under the bonnet on the 996 and if you remove the plastic trim you could unplug the cd, and pretty much if you have a squeak the pump is all that is left running. That said you could have the beginning of a brake sevo diphragm splitting and a tiny split may well manifest itself as a squeak or squeal, and is darn site easier to check before you as you say lash out £500 on a new pump. £500, I thought the throttle body at £670 was bad enough. I presume that is the price for a genuine Porsche Part. Porsche Centre Exeter have built quite a good reputation for their prices on spares but this might just be on the front engined 924/68 ranges but worth a phone call. Not related but I just bought a two lever column switch from PC reading which was cheaper thne the identical item from an on line independant but I didn't surf every site. Places like Berlyn Sevices now known as Parts for Porsche, Type 911 and design 911 are all places to visit to compare prices

 

[924nutter]

For example Design 911 have a genuine Porsche part fuel pump for £235 suits boxster 996/997. Does the 996 have two pumps?

 

[richard hall]

Hi Mick If you cant tell precisely what it is get a decent indie to check it,Richard may be along later to give some sage advice FYI the roller pumps are VDO I wouldnt let anybody relieve me of £500 just for a pump sprinkled with porshce fairy dust,for that money you can buy the motorsport pump http://www.6speedonline.com/forums/996-turbo-gt2/180764-fuel-pump-system-exposed-couple-pictures.html do a websearch on the fuel pump there is certainly plenty out there onthe american sites as below, Kevin from ultimate motor werks did a great piece on replacing the standard pump with the motosport one just helpful from the point ofview or removing and reinstallling and general info http://www.turboflatsix.com/ultimate-motorwerks-tank-t191.html?s=aec7cfecbdc1728efb0cba74c996c24b& he suggests there are two additional pumps in the tank which are scavenge pumps good luck

 

[mick rowe]

Thank you for your replies The squeal is definately coming from the fuel tank I had a good listen and put my ear to the top of tank and it is deffinately where the noise is coming from I have done a few serches for the pump and most places dont list the pump and say main dealer only What are your thoughts on this comment i read on Rennlist and is this right about resetting the computers on the key if so would that not be a good idea to reset the computers every now and again to make sure everything is working as it should . I have not heard about this The comment I heard that Porsche computer systems sometime lose their place and that if you turn the key to "on" position but not start the car and leave it in the "on" position for a couple of minutes the electronics "reset". I did this last night and today the car now fires right up and the pump doesn't whine.

 

[richard hall]

happy days £500 saved!

 

[mick rowe]

Sadly not richard the above comment was something i read on a forum . i have tried this reset this morning and the pump is still squealing so it has not cured the problem so I am still looking for any advice on this

 

[Richard_Hamilton]

The "computers" don't "lose their place". What the Rennlist post was probably referring to is the routine for resetting the fuel adaption vales in the DME. Over a period of time, the DME adapts the fuelling to account for fuel quality and conditions. The adaption values can be reset to factory default by switching on the ignition for 60 seconds, without touching the throttle pedal, and then switching it off for at least 10 seconds. On the original topic, IIRC the fuel supply on the 996T is returnless, and the pump should only run for a few seconds when the ignition is switched on, but the engine stopped. Does the squealing go on continuously? Also, when you say you have listened to it at the tank, do you mean by the filler neck, or under the battery in the front compartment?

 

[richard hall]

now were is Richard when you need him must be frequenting the cayman forum

 

[Richard_Hamilton]

Don't worry Richard - I'm here! You just needed to wait a few seconds....

 

[mick rowe]

Hi Richard the pump makes the usual sound of pressuring up i then start the car and the squeal starts a couple of seconds later. it is continuos while I am driving and does not really change its pitch and soon as i turn engine off it stops I really am baffled by this as i have used the car all day today locally just lots of small runs stopping and starting and the car runs fine and there is no loss of power As to listening to the sound i have had my ear to the filler cap and also removed the plastic trim and carpet from under the bonnet and then removed the metal dome in front of battery and my pump is under there well the large plastic ring and all the pipes and electrics are there i know the pump is attached to the bottom of the tank as i have searched forums for advice and although no mechanic i have a bit of an understanding of the layout Do you think that at some point the pump will pack up and i will have a breakdown or if i am understanding your post corectly once the pump pressures the system it stops so I guess if it does pack up it should be that the car just wont start rather than cutting out as I am driving If it is the pump then I will get it changed but dont want to put a £500.00 pound part on the car only to find it is something else and the new pump does not sort it. I have been down this road with my van being told i need to change a part done so and it has not fixed the problem wasted £150.00 because it was something else lol Thankyou for your help on this one kind regards Mick

 

[Richard_Hamilton]

The pump will run for a couple of seconds on switching on the ignition, and will then run when the engine starts. So it does sound like it is only happening while the pump is running. Seems like you have checked the right things, and it must surely be the pump itself. I assume it must be a bearing has failed in the pump which is making the noise. If so, it isn't going to fix itself, and will surely fail at some point. My only other thought is that it might be a split tube, making a reed-type sound, but I think it less likely.

 

[mick rowe]

Thankyou for your help I am going on holiday for 2 weeks now so will have another look when I get back and probably go for the new pump I will post on here if it fixes the problem if anyone else has any opinions on this please post and i can look at them when I get back thanks again Mick

 

[s shepherd]

Fitted a petrol pump due to mine stopped working, now some times my new pump ( I think the pump ) makes that noise 1989 3.2 sse cab any ideas