Hi guys after replacing the blue temp sensor I seem to have another issue ??!!?? I've noticed I can hear the high pressure tank under the car. I've compared the noise to my mates car which is the same year car and you can't hear his at all apart from when it primes I replaced the pump in question last week for a brand new Bosch pump so I now the pump is good. I've noticed that when I rev the car the pump quietens down then when on idle is very loud It sounds like its straining !!! ?? I was maybe thinking the intank pump is not supplying the high pressure pump with enough fuel ? Am I along the right lines ? Would an in tank pump cause lack of performance ?
Are you losing fuel anywhere? or perhaps you'll fuel filter is clogged due to age/running in the red too often like me. I'm just thinking that perhaps the pump is making that noise because its trying hard to drag the fuel through.
Hi guys replaced the intank pump and the high pressure pump is still loud ? I know the the high pressure pump is ok because that was brand new Bosch unit that I replaced last week I did notice that when I pulled the pump out a previous owner had badged the wiring going to the pump as I had bullet connectors connecting the wires and the pump was half the size of the new pump. But to be honest the pump was fine till last week when out of the blue the original hp pump started being loud hence why I replaced it but the the noise didn't change even after replacing the hp pump So that's when I decided to replace the intank pump but to no avail. Should the intank pump be heard ? Reason being is I can hear the intank pump working but rather than a constant flow sound it sounds intermitant Almost forgot to mention when replacing the hp pump I replaced the fuel feed from the tank to the hp fuel pump box with proper rubber fuel hose But the noise was there before I replaced the hose and after so again by my thinking I can rule that out ? What could be causing this ? I really don't want to have to replace the hp again as I wasn't cheap Any ideas guys
So it sounds like the in tank pump is a good pump, but is it actually getting power? I've made this mistake in the past Unplug the main pump and you should hear the in-tank pump prime when you turn on the ignition (you don't need to try to start the car).
Got a similar problem. mk2 16V. Just replaced the fuel filter and lines and now no fuel is getting to the front of the car. Does the mk2 have an in tank pump? Do i have to prime the under car pump? If so how...... thanks Jon
Hi mike yep the intank pump is good I've just replaced it and yep you can hear it prime that's the first thing I checked. You can hear both pumps prime but the once the engine is running you can hear the high pressure pump making a loud buzzing noise and hear the in tank pump pumping too Whilst on idle should the intank pump sound constant ? Reason I ask is because I can hear the intank pump but sometimes it sounds like it dips in flow iif you know what I mean This is ****ing me right off now !! I don't the best patience in the world !!
My problem is a dead lift pump. A mate has given me one to try and now the car runs. If everybody doesn't mind a hijack, the car will run without the lift pump right? But once drained down, the main pump wont prime. Does that sound right? My lift pump has probably been dead for a while... Is an 89 8V lift pump the same as a 91 16v one? Jon
As far as I know all the Mk2 Golf lift pumps are the same, and I've swapped between golf and Scirocco (post 84 have a lift pump) in the past. The pump is the same although the bits that fit around it are a bit different.
Hi mike fair question but all the pipes are the correct way round also my old high pressure pump was fitted to my sisters mk2 digifant gti and works without a problem !! No noise what so ever. I'm at a loss with the poxy thing !!
Hi mike fair question but all the pipes are the correct way round also my old high pressure pump was fitted to my sisters mk2 digifant gti and works without a problem !! No noise what so ever. I'm at a loss with the poxy thing !!
sounds like fuel isnt getting from the lift to the main for whatever reason, check the fuel lines arnt kinked or blocked. the lift pump should make a constant noise no matter what, all it does is keep the reservoir topped up. did you swap the whole thing, or did you just change the electric pump? check the pipe from the pump to the level sender is clear, theres a metal valve thingy on some this may have failed. So the lifter is 100% runnign when the main is? you'll have to put your ear to it. maybe its not gettign enough power, on my my2 sometimes the main pump would cut as the fusebox couldnt supply enough power to run both pumps, i had to replace the fusebox to fix this the black pipe from the lift pump should go to the larger fitting on the bottom of the main pump, this is the feed so it will have an arrow on the sender unit pointing at the pipe. the blue pipe should go to one of the connections on the top of the filter housing, this is the return to the tank and the arrow will be pointing away from the pipe. all mk2 lifter pumps are the samespec, but the level sender housing differs pre/post-90. pre-90 are 3 pin, 90spec are 4 pin. there are a couple different types of pump fitted over the years with different size inlet but as long as you get the matching filter to go with the pump any will swap over regardless of age.
Hi jonny I replaced the pipe from the tank to the black fuel box with the correct bore rubber fuel hose I've changed the actual black box the fuel pump is mounted in. I don't have any leaks at all If It was the wiring why all of sudden would it just go ? Could it be the fuel pressure reg ?? I think I'm going to change the intank sender unit a see if that makes a difference ? I'm stumped
i dont think its the wire, as its common to both pumps. im wondering if there is an issue with the fusebox, relay or fuse which is preventing enough current to supply both pumps, as i say on mine the fusebox needed to be replaced because of this issue. i would look at the level sender assembly too, in particular look at the rubber pipe from the pump to the level sender, if its broken down inside that'll stop good fuel flow to the main pump
Any idea what the metal valve thingy is, in the lift pump assembly? The rubber hose in mine was all corroded so I took it out and used a piece of silicone hose instead.
Could be? I haven't noticed any ill effects of not having it, so far. Except the silicone hose disintegrated within a week in the fuel, used proper fuel hose this time.. I wonder if the main pump suffers on prime if some of the lift-pump supply drains back to the tank on switch-off.
i wouldnt have thought so as it has a fair amount of reserve. though if the main tank was empty theres a chance the lifter could allow it to drain a bit by capillery action, though you wouldnt loose much before the level dropped below the pipes as they're right on the top. maybe its more to help stop the lifter pump itself de-priming in these circumstances, but even then i think it would soon sort itself out
