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Discussion Starter · #1 ·
When stopped at a junction today, I decided to inch forward a little so that I could see into the road better. So I move forward, and when I came off the gas, first the car started shaking quite violently, secondly the revs started bouncing (650RPM - 800RPM) and then the car just stalled - the engine just switched off! This has never happened to me before, so I then go to restart the car, but it wouldn't turnover. Tried a second time, gave it some gas, and after a couple of seconds, it finally spluttered back.

Then shortly after, I was stuck in traffic, so it was pretty much stop and go for quite a bit. The same thing happened again just as I came to a stop, although this time round, it took quite a long time to restart the car - I held the key in the 'starting' position, and pretty much had to floor the gas, until it finally came to life again. So far, I've had the car stall on me twice, then I encounted another problem immediately after.

When moving off, the car was shaking violently, acceleration felt lumpy, and the engine felt as if it was going to cut out - felt so embarassed as there were people walking past. This problem continued for a little while, then went away, because when I gave it some, it seemed to pull normally. So basically, I was wondering whether anyone has any ideas of my four problems below?

1) Idle revs bouncing Common
2) Idle car shaking - which leads to it stalling Recently
3) Accelerating feels like the car is going to cut out Recently
4) Cannot restart the car immediately, need to wait around 3 seconds and floor the gas, it should restart straight away Common
 

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Have you tried cleaning the throttle housing? Could be due to hose letting air into the engine, listen out for constant hissing sounds. [:^)]
 

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Discussion Starter · #3 ·
Nope I haven't yet, as I don't have the software to adjust the ecu afterwards.

The hose, which hose are you referring to, is that hose related to the throttle body?

By the way, I do hear a hissing sound under moderate acceleration with the window open. [*-)]
 

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The hose i am referring to is the brake servo hose.  Mine has a crack in it, and i can hear hissing.  It could be some other hose though.  Open the bonnet, and listen out for constant hissing.  This could be the problem, or could be adding to another problem.  I am yet to book mine into the stealers, as this was part of a recall they done.
 

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Discussion Starter · #5 ·
Nah, there's no hissing from the engine when it idles. There's only a hissing, kinda like an air sucking noise under acceleration though.

Had another problem today, when moving off or acclerating through the gears, there's kind of a knock felt from the engine, and the car has very poor acceleration - absolutely no power in the upper gears. For example, when moving off from a standstill, the acceleration is lumpy, and there's a knock that can be felt from the engine, same for the other gears, and it knocked once when I was cruising at 40mph. This wasn't intermittent, it was constant for my entire journey. Does this sound like a misfire?
 

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Discussion Starter · #6 ·
Got it on an ECU, and it came up with Crankshaft Speed Sensor, so I was wondering, whether a faulty speed sensor can lead to my problem above?
 

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Can you post a picture of your engine bay? Than some of us may be able to highlight area's in which to check.

Some problems may be:
MAF - dodgy idle
Coolant temperature sensor - lumpy acceleration and starting problems

These two cause loads of seemingly unrelated problems so alot can be eliminated if these are at fault.

How old is the car? Is it modified?
 

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Discussion Starter · #8 ·


I think the car is misfiring, because on a couple of occasions, when accelerating, the engine knocks/shakes and doesn't generate much power.

The car is seven years old, and it is completely standard.
 

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I'm not sure whether the 1.6 has a MAF, but I would recommend changing it if it does. I changed mine and it cured all the flatspots and lumpy idle problems.
 

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Hi again,

This is a rough guide to try and get you going better, starting with the easiest.

OK, you do have a MAF, it is located after the airbox, and circled 1 in the attached pic, if you can unplug the loom from it and just leave the electrical connector out preferably secured so it can't move. If the car runs better with this removed, your MAF is dead and only a new one will completely fix the problem. You can try and clean it, using electrical contact cleaner, but it will only put of the inevitable.

Check your brake fluid resevior cap is screwed on tight, circled 2. If it is loose, moisture can be absorbed by the fluid and impair it's performance. It is somehow connected (on 20VT engines at least) to the rocker cover for some sort of pressure or vacuum function. It may not be related to your problem, but is well worth checking. At best, if the fluid spills onto a cold engine/paintwork it will do some damage, a hot engine and it will probably ignite.

Lastly check your vacuum hoses connected to the inlet manifold, 3, these are easily split, and without the vacuum, the engine isn't operating correctly.

Posted Image

See ETKA image for close up of hose orientation. The vacuum unit is No. 18 and hoses 21, 22, 23
Posted Image


Hope this helps,

Andy
 

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I as experiancing problems like this today as well. Although i have these fualts from VAG-COM

Address 01 -------------------------------------------------------

Controller: 06A 906 032 DR

Component: 1.8L R4/5VT 0002

Coding: 11500

Shop #: WSC 00000

3 Faults Found:

17608 - Boost Pressure Control Valve (N249): Mechanical Malfunction

P1200 - 35-00 - -

17705 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)

P1297 - 35-10 - - - Intermittent

16502 - Engine Coolant Temp. Sensor (G62): Signal too High

P0118 - 35-10 - - - Intermittent

Readiness: 0000 0000
So i think mine is the Engine Coolant Temp. Sensor
 

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Discussion Starter · #14 ·
LaSarthe&Back,

I've checked the brake fluid cap, and the three vacuum hoses, they all look and feel like they're secured tightly. Haven't tried the MAF loom, as it was getting dark and couldn't really see well.

At the moment, my main problem is the engine cutting out when slowing down to a stop, and the engine knocking/misfiring when accelerating - which effects the engine performance. Both these problems are intermittant.

So going back to what the VAG-COM discovered, do you reckon a faulty Crankshaft Speed Sensor is the cause of those problems above? In addition, the mechanic said a Lambda Sensor also came up, but he reckons this is caused by the faulty Crankshft Speed Sensor, so he said leave it for the time being to see if the Crank Sensor will sort it out.
 

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Yes of course, if a diagnostic has picked up a faulty crank sensor, get that sorted, I've never heard of it going tho. Have you changed your coolant temp sensor?
 

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Discussion Starter · #16 ·
No I haven't.

But when I get the Crankshaft Speed Sensor replaced, I'm going to ask for the Throttle Body & MAF to be cleaned, and the Temperature Sensor to be replaced.

Hopefully:
- Throttle Body/MAF clean will sort out the lumpy idling
- Temperature Sensor change should sort out the warm start issues
- Crankshaft Speed Sensor change should sort out the engine cutting out and knocking/misfiring under acceleration

Does that sound reasonable do you think?
 

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i am having the exact same problems! and i dont know what to do, i have replaced my temp sensor cleaned the throttle body and that has made no difference, i also replaced the crankshaft sensor and the fault still came back on it!

did you manage to get yours sorted?
 

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You might want to try looking at the EGR valve as from what you have described sounds the the same as what happend to my 1.6 and it turned out to be the EGR valve was stuck open due to the amount of carbon buildup on it.

After a while it would not close and the car would not start and only changing it for a new one solved the problem

part was 108 quid

Andy
 
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