Help! Car is running low revs and cutting out!

[Rachel]

Hi :1zhelp:

I'm new to this site. I've read quite a lot on here but thought I would post up my problem.

I have a W reg Volkswagen Golf 1.4 which I've had for 2 years.

When my car went in for it's MOT back in May I was told the engine management light came on while they were testing the emissions and advised that the Lambda sensor may need replacing and cleared the fault. They also said there was a hole in the exhaust so they replaced it and told me this could also be a reason the engine management light came on.

I have noticed over the last few months that the revs have been fluctuating between 500 and 700 and dropping as low as 400 when idle (the revs have always been at about 700) and occasionally my car will cut out while I am driving, usually as I am dropping down the gears. I have recently had a lambda sensor replaced as I guessed this was the problem (after doing a few searches on the internet and the garage telling me it may need replacing). This seemed to sort the problem for about a month. It has now starting cutting out again and the revs are dropping very low, it also doesn't run very smoothly, especially in 3rd gear. Does anyone have any idea what it could be? My car hasn't had a service for at least 16 months as my funds are limited. My car is going into the garage on Saturday to be hooked up to their machine to see if any faults will show and they suggested if I couldn't afford a service to at least have the oil and filter changed.

A few months ago I also noticed that my water was going down very quickly. I friend had a look and told me they thought the head gasket may need replacing. I took it to the garage to get it checked and they said it wasn't the head gasket. They couldn't find a fault apart from the pressure and suggested I change the cap which seems to have cured that problem. I am also having to top up my oil more often than usual.

I'm just trying to explain the problems I have encountered over the last few months just in case they are related.

Hope you can help.
Rachel.

[Rachel]

My car went into the garage on Saturday and they couldn't find anything wrong with it!

They cleared out the breathing system as it was a bit clogged. Apparantly, all the short journeys aren't good for my car!

I'll see how it goes.

Rachel.

[Rachel]

Well my car lasted just under 2 weeks before the engine management light came on again!!

This time there appeared to be nothing wrong. The car was running fine. Until I get it into the garage i guess I won't know what is wrong with it.

Any ideas???

Rachel.

[Rachel]

Well here is another up date for those of you who may be interested.

My car went into the garage today to have the fault read. I have an intermitant problem with the Lambda sensor. As they have just replaced this they said that this wouldn't be the problem and that it is possibly the wiring to the lambda sensor. They checked it all and cleared the fault. But I have a feeling that I will be back to the garage in the very near future!!!

Rachel.

[onzarob]

Nice to see you keep the thread updated it doesn't go unread.

Don't rule out the new sensor being faulty if the light comes back on, it has happend to me before.

Good luck

Rob :D

[Rachel]

It's been 2 1/2 weeks since I posted my last message, and guess what? Yes, that bloody engine management light has come on again!!!

The car is going into the garage again on Wednesday and they are going to check the wiring.

I'm getting a bit fed up with it now and was hoping it would be sorted before the really cold weather comes are way. I am thinking of getting rid but can't really afford to do that! Anyone want to buy a dodgy Golf???

Rachel.

[Rachel]

Another update.

The fault read that it was the lambda sensor again so the garage had an electrician to replace the pins. They cleared that fault and another one appeared. They replaced a sender unit but not to sure what that is but they did tell me that this can apparantly cause eratic revs??

Someone told me the other day that a friend of their's had a Golf, same year, model etc and they are having the same problems. They took the car to a mechanic that told them that he has seen this problems loads of times and told them that it was the air filter?? Do you think it is worth changing?

Lets see how long it is before the engine management light comes on again!

Rachel.

[adamss24]

The ECU relies on a whole aray of sensors to make the engine run at optimum. To make the engine efficient the ecu is trying to stick to the stoikiometric rapport off 14.5: 1 of air to fuel to maximise efficiency. However it cannot keep that all the time so he has to make constant adjustments so thats why the lambda probe is there for. When an engine is hot and runs lean it produces more NOX(nitrogen oxides) and when it runs rich it returns poor economy but its easyer on the environment. When the lambda sensor fails he is pushing too much fuel that gets the catalist verry hot and thus the emission lights came on! Thats why its important to have a lambda probe within spec. Usually garages fit poor quality sensors and they deteriorate very quick.

[Rachel]

5 days later the light is on again!

I not too sure what the problem is! Should I be losing all power when this happens?

If the fault reads the lambda sensor again is there anything else that's related to it that could be the problem. Is it coincidence that this all started after I had the exhaust replaced in may?

Rachel.

[adamss24]

What is the mileage? Has the catalyst been replaced ? It could be that the catalyst may be plugged and not doing a propper job and lambda sensor knows it and turns the emission light on. Is the engine iddles steady at 900 rpm or is it going up and down?

[Rachel]

It has done just over 66K. I don't think the catalyst has been replaced.
The revs are a lot steadier than they used to be but not really steady.

The car was fine before it went in for its MOT and they told me that the engine management (Exhaust emission light) came on while they were reving it to do the emission test and it hasn't been right since.

[Rachel]

I have now been told by a different garage (over the phone so they have not read the fault) that it might help if I run my car on super unleaded fuel.

Also the car may need the throttle body cleaning out? He says that this is probably why the car's rev's are all over the place.

They also mentioned something about the mass metre??

[Gaston]

Rachel
Ive had similar problem with my mk3 golf 1.6 cutting out at junctions running very badly and jerkly at low speeds. It became dangerous in the end. Its a frustrating problem that you can throw lots of money at to resolve. In the end I found out it was the idle control valve that need replacing my car has 135000 on the clock. Not sure if the fuel injection is similar on a 1.4 but guess it probably is very similar. GSF parts have best prices cost me £76 to buy part which is nearly half that of the dealer. Its an easy part to fit but make sure you disconnect the neg battery terminal first. One easy way to test if this is the problem is to adjust throttle cable near throttle body so that it doesnt press back on the idle switch when you lift foot of gas. I found that doing this did prevent the stalling and jerky running straightaway although on cold mornings it was getting difficult to start car. Now have new idle valve starts a dream. I did also find the lambda sensor was faulty on mine and replaced it but this was not cause of jerky problems and idle control more a contributory factor to poor running of engine as air fuel mixture not right. Good luck let me know how you get on

Gaston

[mjd2689]

HI,

I am having kind of the same problems with my Audi A4, had the rev counter bouncing up and down, and sometimes cutting out. I think its ok when cold starting, because when i start up, it atomatically makes the revs up to around 1250 and keeps it there for a few mins just to warm the engine up.

After that, yes it still bounces and cuts out. I know your pain, my car has been to the garage 3 times this year.
1) The engine management light came on, took it to the garage. They whacked it on the diagnostic machine, crank sensor needed changing, £100.
2) Engine light came on again, about 2 days later, typical. Took it to the garage, whacked it on the diagnostic machine, cam sensor needed changing, £80.
3) Failed the MOT 2 days ago on emissions!!! WHAT MORE!!!!!!

I have been on the forum for a few hours reading up. I think the problem is the mass airflow sensor. This measures how much air goes in and tells the ECU how much fuel to put in, simple, until it goes wrong.

I am now fed up of throwing money at monkeys who happily take it off me and do not fix my car!!! :aargh4: :aargh4: :aargh4: The mecahnic Told me about £200-£300 "SHOULD GET IT SORTED". Since then I have been onto a company this afternoon who supply these MAFs (Mass airflow sensors). They cost........£40-£100. That's it. Even better is they take about 5 mins to fit and you can easily do it yourself even if you know nothing about DIY. Undo 2 screws, take out the old, put in the new, do up the screws, DONE!!! :biglaugh:

So, I think I'm gonna give that a go one afternoon this week and save myself a few hundred quid.

While speaking to this company, he said about the lambda probe also as you have, so might give this a go as well if its not a big job.

Will check back soon and let you all know how it goes!!!

Fingers crossed!

[Gaston]

Im no authority on this subject just learning myself but did read an awful lot of forums.

May be worth cleaning MAF sensor. apparrantly the little wire can get coated with dirt which affects its operation. You need to be very careful when cleaning. Best go to the volvo owners forum theres loads of reference stuff on doing these things yourself and they use the same bosch fuel management systems so are very similar.

Your problem with cutting out does sound similar did you try the test I mentioned above to adjust throttle so that idle switch is not operated. If this stops your car cutting out at low speeds particularly when you depress clutch and take foot off gas then you know its idle control valve.

On lambda sensors mine was £50 difficult to access car underneath had to get axle stands on one side of the car and jack it up to get underneath, then get the right spanner 22mm I think. Again these things do have a shelf life of 50 - 100k miles if it hasnt been changed and you have high mileage it'll probably save you money changing it anyway as car will run more efficiently and your emmissions will improve. The diagnostic man I paid was good he could tell wether the lambda sensor was outputting right voltages or not and assess its health.

good luck let us know how you get on keep percevering youll get there.

[mjd2689]

Hi, thanks for your advice on the problems, I will be sure to give them a go and I will let you know how it goes, should have a response by the end of the week, that's when the dreaded MOT retest is. :( Thanks!!!

[Anni]

[quote=Rachel;7038]
Also the car may need the throttle body cleaning out? He says that this is probably why the car's rev's are all over the place.

quote]

That may well be your problem. Ive had problems with my golf (1999 mk4) since I bought it despite a low milage of 47k, fluffing, not idling consistenly, cutting out when dropping gears and stalling when trying to do gentle manouvers. Had the throttle body cleaned yesterday and its a new car, have heard of this problem with then before. Worth having done!

[Rachel]

Thanks Anni,

I will certainly get this done and see how it goes.

The engine management light is back on again! I've just had the plugs changed and i've put a tank of optimax in it (although I don't think I really need to)

I think I might take it to a specialist VW garage and see what faults they read.

Thanks everyone for your helpful advice.

Rachel.

[Anni]

If you do take it to a dealer dont let them fob you off with a new throttle body. Make sure they clean it!! The only way it could be broken is perhaps if its an electronic one. If its cable operated the only thing wrong with it (99% of the time) will be dirt. Ive heard of people having to have them replaced when they needent have.

Good luck, hope it gets sorted :Blush:

[viking power]

I used to run a vauxhall senator with a similar irratic idle. The problem was caused by the engine breathing, depositing oil residue in all parts of the intake system. I would certainly check the idle control valve and give it a good clean out with carb cleaner.
I'm no expert on the VW (although my girlfriend as now bought a golf and I've bought a LT35 van so that will all change) engine so I'm not sure how the engine breathes / vents and whether they are subject to residue build up in the throttle housing etc.

[VW Techniker]

Hi Rachel,

It sounds to me as if your car needs its throttle valve adapter cleaning. They become carbonised with oil diposits and the ECU is measuring the position of the throttle but its not corresponding with the amount of air being drawn in due to the carbonisation, therfore giving you a LAMBDA fault (or Long Term Fuel Trim Adaption Limit Exceeded is the actual fault) Do not be tempted to change the Oxygen Sensor... 9 times out of 10 the sensors are telling the truth. But less qualified technicians often overlook this and blame the sensor, costing you valuable money.

Good luck

Rob

[auiron]

This website, that I came across today, seems to be very helpful and if you can spare the time searching through it, we may all be able to help one another a lot more: http://www.2carpros.com/first_things/check_engine_light.htm

[VW Techniker]

This website, that I came across today, seems to be very helpful and if you can spare the time searching through it, we may all be able to help one another a lot more: http://www.2carpros.com/first_things/check_engine_light.htm

Hi auiron,

Had a look, not bad, but it's American... They are a tad behind in vehicle technology... If they spent less time bombing maybe... No let's not get into that one, thats for another forum.

Rob

[auiron]

Hi auiron,

Had a look, not bad, but it's American... They are a tad behind in vehicle technology... If they spent less time bombing maybe... No let's not get into that one, thats for another forum.

Rob

Hi Rob, you are quite right, but these fuel problems can cost a lot of money on a trial and error basis. If the owner is very good on the hands on side, then they could spend 20 hours enjoying themselves over the weekend and travelling around breakers yards buying bits and pieces for a few pounds on a hit and miss basis.
Unfortunately, most of us aren't quite like that and trust garages.
We have 3 cars and one has a problem that will be sorted out over time. Difficult with one car though.

Extra guesses: blocked fuel filter, dodgy fuel pump, filthy air filter ( gunged up fuel system that additives might clean up ), something is loose ( in the old days a loose carburretor could be the problem ) and so it goes on.

[VW Techniker]

Hi Rob, you are quite right, but these fuel problems can cost a lot of money on a trial and error basis. If the owner is very good on the hands on side, then they could spend 20 hours enjoying themselves over the weekend and travelling around breakers yards buying bits and pieces for a few pounds on a hit and miss basis.
Unfortunately most of us aren't quite like that and trust garages.
We have 3 cars and one has a problem that will be sorted out over time. Difficult with one car though.

Extra guesses: blocked fuel filter, dodgy fuel pump, filthy air filter ( gunged up fuel system that additives might clean up ), something is loose ( in the old days a loose carburretor could be the problem ) and so it goes on.

Hi auiron,

I know where you are comming from. The problem we have today is the complexity of the vehicles involved, as a garage owner myself, I spend fortunes on training to keep myself updated, and I've been a technician for nearly 20 years.

As a specialist in vehicle electronics I undertake work on behalf of other garages in my area, and it's suprising to find that many technicians look under the bonnet and loose focus on what they are looking at. Im not saying vehicle diagnostics is easy... It certainly is'nt... But there are exact methodical techniques which simplify the task without compromising the result.

Rob

[Rachel]

Hi,

just a quick update.

I have now been driving around with the emissions light on for about 5 weeks. I don't have the time or the money to take it into the garage and I realise I am probably doing more harm than good. I plan to go and get the throttle body cleaned out after christmas and I have been told it will cost £45. I will also have to have the fault read too which will be added expense and then any other problems sorted!

I don't seem to have problems with eratic revs anymore but I have noticed creamy residue around the oil cap and gunky stuff in the breather system. I have been told (by a non mechanic) that this could be condensation from short journeys and from stopping and starting as I drive through a city with lots of traffic lights. I appear to be losing water but not a lot. I have to top up my water now and again. I did have a pressure test a while ago and have been assured that I don't have a head gasket problem.

I tried a tank full of v power fuel (as suggested by a VW expert) but this doesn't seem to have made any difference. I also noticed that on a tank full of fuel I am doing about 50 miles less.

I'll keep you updated and thanks for all your advise.

Rachel.

[VW Techniker]

Hi,

just a quick update.

I have now been driving around with the emissions light on for about 5 weeks. I don't have the time or the money to take it into the garage and I realise I am probably doing more harm than good. I plan to go and get the throttle body cleaned out after christmas and I have been told it will cost £45. I will also have to have the fault read too which will be added expense and then any other problems sorted!

I don't seem to have problems with eratic revs anymore but I have noticed creamy residue around the oil cap and gunky stuff in the breather system. I have been told (by a non mechanic) that this could be condensation from short journeys and from stopping and starting as I drive through a city with lots of traffic lights. I appear to be losing water but not a lot. I have to top up my water now and again. I did have a pressure test a while ago and have been assured that I don't have a head gasket problem.

I tried a tank full of v power fuel (as suggested by a VW expert) but this doesn't seem to have made any difference. I also noticed that on a tank full of fuel I am doing about 50 miles less.

I'll keep you updated and thanks for all your advise.

Rachel.

Hi Rachel,

Your 'non mechanic friend' is correct in saying that it could be condensation, it more than likely is. The creamy residue you describe is being transfered into the intake system via a breather tube directly into the throttle valve adapter, this is causing your running faults.

The oil vapours are designed to be fed into the intake system as part of the combustion process, but of course the oil must be clean and changed regularly.

If deposits of the condensation residue are being fed into the intake system, it will stick to the walls of the intake manifold and could cause further problems even after the throttle valve adaptor has been cleaned, such as carbonisation of valves etc... If this is the case the intake system will need cleaning, not just the trottle body and the engine will need a GOOD QUALITY flushing agent run through it.

For your notes, the garage who want to charge you extra to clear the fault codes are having you on... After cleaning the throttle valve adaptor it will require adaption and you can only do this when the fault codes have been read and cleared; therefore should be included in the price.

[VW Techniker]

Just another thing to add,

Your fuel consumption issues are also due to above reasons.

If your EML is on then the ECU is running the engine on default values rather than optimum values.

[Rachel]

Hi,

I have just called my local VW dealer and they have said that it will cost about 1 hours labour (£91) to clean out the throttle body and the breather system. Is this about the norm? I asked if they would also reset the ECU but told me that would depend upon the fault.

Is the intake system the same as the breather system?
When I get this done is it worth me running a flushing agent through it and what would you recommend (Sorry this sounds stupid but does it go in the petrol?)
Also, am I supposed to be using higher RON fuel in my car? Inside the fuel cap says 95 RON so I'm guessing not.

Any replies to these questions would be much appreciated as I really want to get this promblem solved.

Many thanks,
Rachel.

[Teutonic_Tamer]

American... They are a tad behind in vehicle technology... If they spent less time bombing maybe...

ROTFLMAO - Oh I couldn't have put it any better. Now where are those screen wipes . . .;)

[Teutonic_Tamer]

Hi Rachel

Just found this thread, boy you are suffering.

Has anyone checked to see if you have any cracked or split breather hoses or vacuum pipes? These are often overlooked, but can surprisingly cause a variety of poor running problems.

Rgds

[Rachel]

Hi,

My car has been in the garage again today and the fault code again was the lambda sensor. They told me that there are 2 sensors and they that the garage it previously went to could have changed the wrong one. The mechanic explained to me that there is a sensor either side of the cat (?) and it was the heated one that needed replacing. He told me that this would cost £160 as the part needed to be ordered from VW. He than called me back 5 minutes later to say that he managed to get it elsewhere and would cost £94 fitted.

So now, a new exhaust, 2 lambda sensors and a sender unit later lets see how I get on!!

Rachel.

[Teutonic_Tamer]

Hi,

My car has been in the garage again today and the fault code again was the lambda sensor. They told me that there are 2 sensors

Ohh, that's a little surprising (to me), I thought they only came with one lambda sensor on that age of car, thinking that 2-sensor (upstream and downstream of the main cat) came in about 2001ish. I could be very wrong though, so no flames please, and I'd gladly be corrected. Incidentally, what manufacturers model year is your car? If you look at the 10th digit of your VIN, it will give you either a number, for post 2000 build, or a letter for pre 2000 build. If you arn't sure, post your VIN here, but for security blank out the last 6 digits with asterixes. An Audi VIN will look some thing like WAUZZZ8EX3A******, on a VW VIN, the 2nd & 3rd digits will be VW, so yours would start something like WVWZZZ1J???****** - of the above Audi VIN, the 10th digit is "3", which means it was a 2003 model year.


and they that the garage it previously went to could have changed the wrong one.

Is it possible to go back to the previous garage and ask for a printout of the fault codes your car generated, and how they actually determined which sensor to replace. If the garage only read the generic codes, rather than the manufacturer specific codes, then they wouldn't know which one to change, and just guessed - now proving to be a costly mistake which you have had to pay for!


The mechanic explained to me that there is a sensor either side of the cat (?)

If that is the case, there will be an upstream (before the cat) and a downstream (after the cat) lambda sensor. These two enable the engine management system to monitor the efficiency of the cat (as well as adjusting the air/fuel mix and ignition timing).


and it was the heated one that needed replacing.

Ahhh - sometimes, both upstream and downstream sensors are heated. On the newest cars, this is now the norm - indeed my Audi has 4 heated lambda sensors and 4 catalytic convertors - could get very expensive if a garage used guesswork!!!


He told me that this would cost £160 as the part needed to be ordered from VW. He than called me back 5 minutes later to say that he managed to get it elsewhere and would cost £94 fitted.

Hopefully, they used an OEM spec from somewhere like GSF or ECP, as non-genuine lambdas are well known to be rather troublesome.


So now, a new exhaust, 2 lambda sensors and a sender unit later lets see how I get on!!

Rachel.

You seem to have been given a real runaround - fingures crossed it's now finally sorted.

Rgds

[Rachel]

Hi,

I have checked the VIN number and the tenth digit is a 1. The date of registration is 20/07/2000.

I'm not too sure I want to go back to the garage where they prevoiusly changed a lambda sensor. The garage I took it to asked where I had previously took it and when I told them hey said 'Say no more'. He just said that they are a very old skool garage.

When I had the lambda sensor changed on friday the guy explained the codes to me. He said that reading the fault code and not going into detail would of made them think that it was the sensor that they changed. He had a list of codes which he showed me. I'm hoping that I'm not being conned as this is costing me a fortune! The sensor they used was a Boosch one which he told me was the same one that would of cost £123 + vat from VW.

I now hope my problem is solved and I will keep you updated.

Rachel.

[Teutonic_Tamer]

Hi,

I have checked the VIN number and the tenth digit is a 1. The date of registration is 20/07/2000.

OK, that confirms your car is a 2001 model-year - handy to know for future reference.


I'm not too sure I want to go back to the garage where they prevoiusly changed a lambda sensor. The garage I took it to asked where I had previously took it and when I told them hey said 'Say no more'. He just said that they are a very old skool garage.

Live and learn eh.. Unfortunately, with detailed specialities of modern automotive electronics/diagnostics, you really do need to find a dedicated independent VAG specialist. You could always write to the first garage, asking for the list of codes, because they are legally obliged to provide a detailed written statement/invoice of any work they carry out, and that also includes "workshop notes" (what the mechanics/techs write on the back of the workshop job card) and printouts of any diagnostic tests. Naturally, if it were a cash-in-hand job, with no invoice, and they had rows of polished baseball bats behind the counter, you may feel it prudent to let sleeping dogs lie!!


When I had the lambda sensor changed on friday the guy explained the codes to me. He said that reading the fault code and not going into detail would of made them think that it was the sensor that they changed. He had a list of codes which he showed me. I'm hoping that I'm not being conned as this is costing me a fortune! The sensor they used was a Boosch one which he told me was the same one that would of cost £123 + vat from VW.

Again, this new garage should still provide the printout from the fault-code reader. One garage blaming another garage for shoddy work is sadly a fact of life in the motor trade, and whilst the real cowboys are few and far between, it is an easy avenue for any garage to take. It's good news about the Bosch sensor, if my memory serves me well, Bosch along with Beru were the OEM manufacturers.


I now hope my problem is solved and I will keep you updated.

Rachel.

I think we all join you in hoping you've now finally found a resolution to this.

Rgds

[robsgolf]

Rachel,

Thanks loads for sharing your experiences of your golf. I am gaining useful insights from your findings but not yet sure which part to get fixed on my car. Would love advice from anyone on how to go about getting my problem fixed.
My golf is a 1.6 cl 1994. It has 2 issues, that remain having had the throttle idle switch unit and starter motor replaced last week.

The engine cuts out at random, usually as I come up to a junction or turn - so I guess I must be lowering the gears or in neutral.
- every so often the acceleration goes, even though I am pressing down the pedal. 2 or 3 seconds later the acceleration is back.

Is this the similar to yours? What is the latest? You talked of a red light coming on - that isn't happening to me.

[Kev.trebuan]

You could try the relay part number 165906381 which tells the ecu about the lamda sensor. If you Google this part number, you will see it's apparently a common Golf fault that associated with engine cutting when slowing down.:Blush:

[robsgolf]

Bought the part from my local volkswagen garage. Put it in the place they told me on the relay board bit under the stearing wheel. Didn't change things. The temperature gage went somewhat hot so don't think it helped there.
Seeing as there wasn't one there in the first place I assume there is not meant to be one there now???
Thanks for the suggestion though. Up for any solutions short of spending a fortune at my local garage!