t25 2.0 8v gti lumpy running and noisy fuel pump

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soniquethedog
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t25 2.0 8v gti lumpy running and noisy fuel pump

Post by soniquethedog »

hello , i am struggling to find out what is wrong with my t25 gti 2.0l 8v conversion , its been fine since the conversion 4 years ago , it started a few months back and it felt like fuel starvation , so i gave it a service changing the fuel filter and plugs etc , whilst under the chassis changing the fuel filter i noticed that the fuel pump was making a funny high pitched noise but still working ,the only other fault was the airfilter and air temp senser were wet thru as they are sited in the left hand corner under the air vent , so i dried everything out , but its still the same , i have changed so far ,, fuel pump , fuel filter ( new one still making a high pitched noise ), plugs , coil , HT leads , dizzy cap , rotor arm , fuel pump relay , even tried a different ecu , but it seams to be lack of fuel when you change from 2nd to 3rd mostly , any help would be great before i replace anything else

cheers dave

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Aidan
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Re: t25 2.0 8v gti lumpy running and noisy fuel pump

Post by Aidan »

which fuel pump are you using ?
iirc the golf has a lift pump in the tank as well as the fuel pump , we only have gravity feed; is it better with a full tank ?

soniquethedog
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Re: t25 2.0 8v gti lumpy running and noisy fuel pump

Post by soniquethedog »

hello , its just a universal inline fuel pump mounted on the chassis 12" after the tank just in front of the filter , it doesnt seem to matter how much fuel is in there , even the new pump i have fitted is making the same whining noise

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Titus A Duxass
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Re: t25 2.0 8v gti lumpy running and noisy fuel pump

Post by Titus A Duxass »

Have got the pump mountings cushioned?
VW T3 GTi Camper 2,0l

soniquethedog
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Re: t25 2.0 8v gti lumpy running and noisy fuel pump

Post by soniquethedog »

yes the fuel pump has got rubber mounts on both sides , it has been doing this on and off since august and the pump has been getting louder , and the symptoms are worse , i did notice that the fuel hose was compressed as it left the tank as tho it was under pressure ( like a vacuum) , so i replaced it with rubber hose ,i have just tried the old fuel pump with a bucket of water and wired it up to a battery and it sounds normal , only when its trying to suck fuel from the tank is it noisy

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mrhutch
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Re: t25 2.0 8v gti lumpy running and noisy fuel pump

Post by mrhutch »

it's early FI so it needs the fuel rail pressuried - I can't remember to what pressure.

if the fuel rail has too much pressure then the fuel pressure regulator (FPR) will leak back the excess to the tank

are you possibly using a pump thats not suited? sounds like it may be cavitating to me.

whats the fuel pump from? MK2 golf GTi's (8v) or porsche 944 or waterleaker 2.1 pumps work well
1981 Vanagon Westy Burning oil as fuel...  

soniquethedog
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Re: t25 2.0 8v gti lumpy running and noisy fuel pump

Post by soniquethedog »

i will have a look at the pump later today , but its been fine for the last four years so i dont think its a suitability issue , and the conversion was done by brickwerks,

soniquethedog
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Re: t25 2.0 8v gti lumpy running and noisy fuel pump

Post by soniquethedog »

i think i might have sorted it as i used a can of fuel instead of the petrol tank and the original pump that i put back on was nice and quiet , so i blew into the tank thru the hose to clear any blockage and reconnected the hose to the pump and it ran nice and smooth and quite for about 4 miles before the pump started making a squeaking noise , so im guessing there is something in the tank thats getting stuck in the pipe and limiting the amount of fuel , going to drop the tank next weekend and flush it out

soniquethedog
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Re: t25 2.0 8v gti lumpy running and noisy fuel pump

Post by soniquethedog »

Sorted it thanks ? It was muck in the tank caused by the filler neck ribber being damaged by the weather and muck from the front wheel and was getting in the tank , cleaned it out and is ok

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Titus A Duxass
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Re: t25 2.0 8v gti lumpy running and noisy fuel pump

Post by Titus A Duxass »

soniquethedog wrote:Sorted it thanks ? It was muck in the tank caused by the filler neck ribber being damaged by the weather and muck from the front wheel and was getting in the tank , cleaned it out and is ok

Great news, thanks for the feedback.
VW T3 GTi Camper 2,0l

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