GolfGTIforum.co.uk
Model specific boards => Golf mk3 => Topic started by: Mk2George on 24 December 2006, 15:49
-
Hi Guys, Merry Xmas!
Ok this question has prob been asked a millions times and there are probably a thousand answers but why does my Mk3 Gti stutter when accelerating and have a serious flat spot at about 2k revs? :angry: Where would would you more experienced chaps start with this?
Thanks :laugh:
-
clean out the throttle body. FREE
change the ECU and fuel pump relays. £30
-
sounds like the timing is out a tooth to me, but do a service and clean out the tbody & breathers 1st as blackmk3 says :)
-
Its fixed :nerd: Pulled throttle body off and attacked it with a tin of carb cleaner and it came up looking like new. Not only has it eliminated my stutters on acceleration but now the car will idle freely without me having to adjust the cable to compensate! 2 birds with 1 stone
thanks for the help :grin:
-
I love a free solution to any problem :laugh:
-
Are you able to put a detailed step by step of how you managed to do it? im sure it will help many people including myself.
Thanks
-
Sure,
1. Undo 2 sensors on the air fliter housing then the large clip holding the plastic tubing onto the throttle body then take off the air filter housing and the associated pipes (1 going directly into the larger tube from the rocker cover and 1 going into the very top of the throttle body) Release the throttle cable from the side of the housing and draw it back through the rubber `O` ring mounted on the inlet manifold.
2. Undo the 2 bolts that secure the bracket between the rocker cover and the inlet manifold, there are 2 of these brackets on the rocker cover but only take off the bracket directly under the throttle body, the one on your left if you are standing in front of the car. It is important to take off this bracket as it allows easy access to the 2 coolant pipes that go into the bottom of the throttle body later on)
3. Take out the wiring plug that goes into the bottom of the throttle body under the metal inlet tube. There are 2 clips you need to depress to release this plug, one top and one bottom. It is a multi plug and not one of the smaller injector plugs, there is no need to touch them
4. Now take out the 4 allen bolts that are holding the throttle body to the inlet manifold (2 top and 2 bottom). The top 2 are obvious and are easy to get out, the third is under the metal inlet tube and slightly to the right and the last is just above where you will have just taken the wiring plug from. The last one is the most difficult to get to so I used a short extension bar.
5. The throttle body should now pull free and should only be connected to the vehicle via the 2 coolant pipes that go into it from the bottom. Take off the gasket and renew (Ive a feeling that this gasket could have been one of the main reasons for the problem)
6. Pull the throttle body out over the top of the engine past where the bracket that you took off earlier was and release the clips holding the 2 coolant pipes onto it. Try to keep the pipes pointing skywards so that you dont loose much coolant. With these 2 pipes off then the throttle body should be free of the vehicle.
CLEANING
There is no need to dismantle the throttle body any further than it already is, if you have a similar problem to what I had then you will find large black deposits inside the round metal housing and on both sides of the round `butterfly` insert in the housing. I used Wynns Carb cleaner (readily available from Halfords) and sprayed all of the insides of the tubing both front and back. I have to say this stuff is great it just blasted all of the crap away right down to the metal. There is a small inlet tube on the top of the throttle body (where you took a hose off earlier on) that leads into the main chamber of the throttle body, make sure you get a few good squirts down there from both sides. Dont take off the throttle potentiometer (black plastic part on the side of the throttle body) as you are asking for trouble messing around with that :smiley:
Assembly is the reverse off taking it off, just make sure you get the small coolant pipes back on the right way around (1 is longer than the other) and ensure you put in a new gasket of some sorts (I used a Frosties box and cut a template and the old one together for extra seal) and also remember to do up the 4 main throttle body allen keys up nice and tight.
You might want to buy some small jubilee clips too to replace the crappy circlips that are on the coolant hoses and the hose to the top of the throttle body.
Thats it, hopefully you will have sorted a pain in the ass problem for an hours work and the price of some carb cleaner!
Good luck! :rolleyes:
-
Fantastic work, really appreciate the time for the write up! Im sure it will help lots of people. Thanks again.
-
after having disconnecting the black plug and refitting the throttle body & black plug, does it have to be programmed. as i have read else where is needs to be programmed using vag-com. i want to do mine but am nervous becuase i won't be able to programme it.
-
no it doesnt need reprogrammed no matter what you disconnect. The ecu has long term storage memory as well as short term memory. The basic program is in a ROM chip which wont loose its contents unless intentionally reprogrammed by VAG or similar system.
-
ok thanks for that i'll have a go at it the weekend, hope it cures it :smiley: