A&Q about 350Z
Q:
Apologies if this has been posted before. I have searched the forums and have tried the various advice but to no avail.
My Mk3 GTI is not well at all.....
When the clutch is depressed the engine cuts out completely. Driving through heavy traffic is a nightmare and junctions/traffic lights a non-starter (literally!)
This is also the case when slowing down to a crawl in 2nd or 1st gear.
I have tried the cleaning of all of the air flow pipes, new filter and even had the airflow sensor replaced (which wasn't cheap!) and still no joy. There was a fair amount of gunk to come out of the pipes but it has made no difference at all.
I'm totally out of ideas and am very limited in respect of available time to take the car in to a mechanic (and after the replacement of the air flow sensor on his advice am reluctant to do so again)
If anyone has managed to cure this with their own Golf or has words of wisdom I'd be really grateful.
Thanks
Steve
A:
Throttle body needs a clean, or the ECU relay possibly needs changing.
It's a common problem with the Mk3 by the looks of things.
Can you tell mine does it too?
A:
Mk3’s cutting out is a common problem but is usually rectified with a simple cleaning out of the throttle body. I’m assuming its an 8v Gti not 16v.
Does the car start and drive ok? Just cutting out off throttle or is it running rough all the time?
If its just cutting out I’d still say it’s a problem with the throttle body. Did you really thoroughly clean it out and make sure not of the passages are blocked too.
A:
Yep, 8v....
Once I'm on the open road it drives as smooth as ever. It is only when I dip the clutch when stationary or in slow traffic.
The throttle body - I haven't touched that but will give it a go tonight.
How technically proficient do I need to be to tinker with this?
A:
A bit better than me...
I can see 3 allen bolts but can't see the 4th.
I still haven't done mine...
At least it's teaching me heel and toe again...
A:
with mine, i can stop it idling by a) disconnecting the ecu's water temp sensor (2 pin temp sensor on the gearbox side of the head). with it disconnected, the ecu thinks its cold and runs super rich.
also there is a vac going from the intake man. (just after the throttle) with a vac pipe going ot the ecu (under the windscreen).
if that pipe has died, it wont idle.
check those and check your plugs for sootyness
A:
Oh in that case then problem solved! Its the throttle body, I'll put money on it. I thought you'd already done this. ALL mk3 8v's will do this eventually. There are 4 allen bolts holding it to the intake manifold, I'm guessing the one you can't see is the rear lower one but you can feel it and they shouldn't be mega tight.
This said though you don't actually need to remove it to do the best part of a good job. Just remove the plastic pipe that feeds the throttle body from air box so you can look into the body. You'll see the butterfly right infront of you. The if you (or get someone else) hold the throttle wide open so that the butterfly is now open. Then get a rag and wipe all around the inside of the throttle body and the edges of the butterfly and that should stop it cutting out. Its a 10 minute job from start to finish.
To do a proper job you really need to take the throttle body off and clean all the air ways. And if you do be careful with the gasket between the body and the manifold, you can re-use them if they're not damaged or just buy another one before hand (think they're under £2 for main stealers) This is maybe a 15 minute job start to finish!...or have I just done it too many times!
This problem is as far as I know THE most common mk3 8v running problem.
A:
Thanks guys. I eventually got around to cleaning out the large airflow pipe and butterfly in the throttle housing. There really wasn't that much residue, sure it was pitch black and greasy as hell but I was expecting a lot more "solids".
I didn't remove the Allen Bolts at the time as I only had a pair of pliers and a rag with me so I am intending to do a more thorough job later in the week. However, I drove the car into town in lunchtime traffic and it didn't drop revs or stall once!
Best wishes
A very happy Steven
A:
The mk3 8v GTi throttle bodies don't need much gunk in them to stop them working properly. You'll probably find what you have done is enough and complete removal of the throttle body isn't neccessary. Up to you.
Sam