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Model specific boards => Golf mk2 => Topic started by: InsightMusic on 02 November 2016, 14:32

Title: Car stutters/loses power when you floor the accelerator (Video added)
Post by: InsightMusic on 02 November 2016, 14:32
Hey everyone,

The is an issue I came across on Saturday morning on my way to work. First time i've ever had this sort of issue and i've owned the car for over 2 years.

The car was working perfectly fine until I got on the A1 motorway and put my foot down. There was a massive lack of power and if the car was standing, trying to set off was incredibly hard (Foot down/high revs).

I was able to wing it to work as having the manual choke on full gave the car a little more power back.

I had the RAC come out after work on Saturday as the car wouldn't start (Engine cranking but no start up). He had a look around and noticed the earth cable that went from the Weber carb to the rocker cover was a little loose, so he tightened it and funny enough it worked.. For half hour anyway.

That's now been replaced but the issue still remains.

I'm driving a Mk2 Golf 1.8 GL - recently fitted Weber carb with a manual choke.

Any help would be greatly appreciated!

Thanks,
Stefan
Title: Re: Car stutters/loses power when you floor the accelerator
Post by: InsightMusic on 02 November 2016, 17:16
To add to this...

Just changed the mechanical fuel pump and still no difference. I've just done a quick check and when I'm sat, the car idles great, but if I keep my foot on the accelerator, as soon as it hits 3000rpm, the revs shoot back down and the car stalls.. It's quite odd.

I'm starting to think there's a fault in the fuel line. The fuel filter and fuel vapour separator (I believe it's called) were both changed when I fitted the Webber carb only 6 months ago.

Thanks,
Stefan
Title: Re: Car stutters/loses power when you floor the accelerator
Post by: lemski on 02 November 2016, 19:21
Is it when its warm only. Only carbed thing ive had was the mechanical pump on the side. Diaphram was f**ked.


Failling that. Clean the rotor cap and plugs.
Maybe chuck a coil on it as a last resort.
Could well be ignition side
Title: Re: Car stutters/loses power when you floor the accelerator
Post by: InsightMusic on 02 November 2016, 20:36
Quite possibly, hard to tell.. This morning I drove 15 miles and it was fine. I then went back out 2 hours later and after 5 minutes it happened, so quite temperamental.

I'll give the distributor arm and cap a good scrub. I do actually have a spare distributor, should I try replacing it?

When do you mean exactly when you mentioned 'Chuck a coil on it'?

Thanks,
Stefan
Title: Re: Car stutters/loses power when you floor the accelerator
Post by: lemski on 02 November 2016, 20:52
When coils get how they play up.
But then what your describing to me sounds electrical.
Chuck the dizzy on itll rule out hall sensor if they have them. Long time since i looked at a carbed mk2.

Also the ign amp in the scutlle.
Where abouts are you mate. If you not too far i don't mind coming and having a gander
Title: Re: Car stutters/loses power when you floor the accelerator
Post by: InsightMusic on 03 November 2016, 07:52
Could well be electrical, shame I haven't got a multimeter..

I have read a few times that it could be an issue with the hall sender, but what i'm not understanding is why it's okay one day, but worse the next.. I'll replace the distributor today, see if that resolves anything. I'll also check for vacuum leaks.

I'm based near Bedford in Bedfordshire.

Title: Re: Car stutters/loses power when you floor the accelerator
Post by: lemski on 03 November 2016, 09:08
Too far away for a afterwork drive. Haha
The wires get weak and brake on the hall senders so they conta t then dont.
I replaced the hall on my dizzy and that was a different design with out wires just metal strip straight to the plug.

If you have a coil its another thing ruled out.
Title: Re: Car stutters/loses power when you floor the accelerator
Post by: InsightMusic on 03 November 2016, 17:55
Replaced the distributor today (luckily I had a spare one going) and all seemed to go well when I took it out for a drive. Gave the plugs a change and gave the ignition leads a good clean too.

I also replaced a majority of the cables/connections such as the battery terminals, alternator cable and starter motor cables. I don't think they could have been the cause of the issue, but it shouldn't do the car any harm for sure!

Haven't played around with the carb at all today, so we'll see if the issue occurs tomorrow.

Thanks,
Stefan
Title: Re: Car stutters/loses power when you floor the accelerator
Post by: InsightMusic on 04 November 2016, 13:04
The issue still persists.. there's a real lack of drive in the car, the acceleration seems restricted in a way, I could barely pass 60 on the A1.

When you press down the accelerator pedal, it feels lumpyif that makes sense? It feels like the fuel is restricted somewhere when trying to gain more power.

When idling its fine, in neautral and revving seems okay now, but when driving it struggles really bad.

Any further ideas? Could there be an air intake restriction?

Thanks
Title: Re: Car stutters/loses power when you floor the accelerator
Post by: hardcrimper on 04 November 2016, 17:44
It could be the carb icing up, I had the same prob on a GL I had years ago , some how but can't remember how, I got hot air to the carb and that sorted it.
Title: Re: Car stutters/loses power when you floor the accelerator
Post by: lemski on 04 November 2016, 18:31
Warm up feed from the exhaust like they have standard til they rot out
Title: Re: Car stutters/loses power when you floor the accelerator
Post by: InsightMusic on 04 November 2016, 19:13
Hey,

I've recently just replaced that hot air intake pipe and the hot air is flowing through okay.

Here's a video I took tonight of the issue...

https://www.youtube.com/watch?v=dVTgKr7bkoE&feature=youtu.be (https://www.youtube.com/watch?v=dVTgKr7bkoE&feature=youtu.be)

Sorry about the video, no idea why it rotated the wrong way... But that's a prime example of what i'm dealing with.

This video shows me pushing the accelerator pedal down half way and keeping it there. There's a huge change in RPM and my foot is steady.

The second half shows me doing the same thing, but this time the car stalls?!?

Thanks,
Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: lemski on 04 November 2016, 21:21
The cars warm obvously. Is it more when its warm then??
I had this on mine but as it was mk3 engine it tuened out to be throttle position sensor.

Have you checked for air leaks around the carb mount? Thatll do some crazy things to the air/fuel ratio and make it rev up and such
Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: InsightMusic on 04 November 2016, 22:05
You can force the issue quite easily, simply by pushing the accelerator pedal down full when cruising in 5th.. Theres an initial delay in response for the first inch or so, then it really just flattens out and lacks a huge amount of power.

It happened on my way home from work but not on the way there, however I could massively feel the restriction on the way to work so didn't push it past 60.

I did a lot of checks in searching for any vacuum leaks, changed a few of the pipes yesterday but found nothing.

I haven't looked into the throttle position sensor however.. Also, I've heard there's a sensor in the air intake system that can become dirty and effect the performance, so i'll have to check that out over the weekend.

Something was mentioned on a YouTube video which read - "I had this problem, the car was thinking too much air was entering the engine and so it was supplying more fuel. A hole in the exhaust near the O2 sensor can do the same thing."

I recently replaced the the exhaust system (3 new silencers) so maybe some damage occurred?

Thanks,

Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: lemski on 05 November 2016, 08:24
Shouldnt have a lamda or a throttle position sensor.
But that sensor in the carb is something to go off.
Also if its when your demanding more from the engine. Ie 5th gear acceleration try unplugging the vaccuum advance of the distributor and going again.

Also show a picture of your engine. Just incase your running something different in there than i think is in there
Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: InsightMusic on 06 November 2016, 09:27
I'm free from tomorrow so I'll be able to check up on the car then.. as of pictures of the engine bay..

(https://s17.postimg.org/c3r3ewet7/IMG_0711.jpg) (https://postimg.org/image/c3r3ewet7/)

(https://s17.postimg.org/hgfxt12pn/IMG_0713.jpg) (https://postimg.org/image/hgfxt12pn/)

(https://s17.postimg.org/oxp588s8r/IMG_0715.jpg) (https://postimg.org/image/oxp588s8r/)

(https://s17.postimg.org/ls4ji19mj/IMG_0717.jpg) (https://postimg.org/image/ls4ji19mj/)

(https://s17.postimg.org/swmcr2gvv/IMG_0718.jpg) (https://postimg.org/image/swmcr2gvv/)

(https://s17.postimg.org/wu9mgh3p7/IMG_0719.jpg) (https://postimg.org/image/wu9mgh3p7/)


take a screenshot (https://postimage.org/app.php)
Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: lemski on 06 November 2016, 09:30
Is that a webber???
Definately the carbed engine though.
Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: InsightMusic on 06 November 2016, 09:33
It is yeah, fitted it in May when the old Pierburg carb completely packed in after the automatic choke locked on. Lots of smoke!

It's been absolutely solid, which is why I can't see that being the issue.
Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: lemski on 06 November 2016, 17:37
Take the jets out and blow them out. Might have some shot in the float blocking a jet.
Didnt realise there was a webber fitted.
I use to have to clean mine out once in a while.
Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: InsightMusic on 07 November 2016, 16:36
Bought some carburettor cleaner today and removed the carb completely. Cleaned it down pretty well, although everything is working on there as it should.

I've also bought myself a new fuel filter and fuel line which i'll fit tomorrow.

I noticed that on the rear of the engine block, it it literally drenched in oil. Not sure if there's anything down there that may have been effected by the oil, but it needs a good clean for sure!

The sensor inside the air intake has been checked and cleaner too.

I haven't put the car back together so won't be able to go for a drive until tomorrow.

Is there an o2 sensor in the exhaust for Mk2's with a carb?

Thanks
Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: lemski on 07 November 2016, 18:22
Shouldnt be because theres no way to adjust the fuelling on the carb to keep the lamba reading in
Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: InsightMusic on 08 November 2016, 16:36
A quick update..

Patched the car back together today and changed the fuel filter along with the fuel line, half a bottle of Redex and a change in Petrol.

Took it out for a spin and the performance was a lot better! I'd say it's still only at 85/90% but it's very much drivable which is great!

I've done loads to the car these past two days. A full clean down of the carb will certainly have helped, but i've also attended to other minor issues along the way.

Tomorrow i'll drive it to work (all 30 miles of it) and we'll see how it goes!

Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: lemski on 08 November 2016, 17:21
Good luck buddy.
Title: Re: Car stutters/loses power when you floor the accelerator (Video added)
Post by: InsightMusic on 10 November 2016, 15:43
Well, it looks like the issue has been resolved! For now anyway..

I'm hoping that maybe it was the fuel filter, but it could well have been a carb issue.

Hopefully the issue won't come back, but I'll keep the thread updated if I manage to find out what was causing it.

Thanks,
Stefan