Roomster 1.4tdi 2007 starting issues

[Jannercornwall]

Hi all . My 2007 plate 1.4 tdi Roomster with the 3 pot diesel hasstarted giving me some issues . It is very slow to start lately and requires a lot of winding over . I have replaced the fuel filter, Just fitted new glow plugs and still no better . I have checked the fuel lines are tight so not drawing air also . When cold it really is a long wind to get it started and the starter sounds sluggish, once warm it starts better , but doing several start attempts once warm results in one not starting followed by starting better . I am not hearing the squish sound from the tank pump when the ignition is turned on like I used to but can here it is working . Having spent a few pounds lately to cure the problem does anyone have any other ideas please . btw !! The cam sensor was replaced two years ago . The car has 102k miles and has been re mapped and once going pulls like the proverbial train. Thanks Jon 

[JEFF-the-Bowman]

Its not helping you but i have the same model/year Roomster and mine does the same. I bought mine last winter and when it seemed to be struggling to crank over i naturally thought it was the battery getting a bit knackered so fitted a new one but it was still the same. All through the summer it was fine but had a few coldish mornings lately and its started being sluggish to crank over. Its never failed to start so i just assumed it was something that they did and didnt view it as a potential problem till i read your post. I dont know how long you have owned your Roomster but did your problem start suddenly or has  it been  progressively worsening  ?

[Jannercornwall]

8 hours ago, JEFF-the-Bowman said:

Its not helping you but i have the same model/year Roomster and mine does the same. I bought mine last winter and when it seemed to be struggling to crank over i naturally thought it was the battery getting a bit knackered so fitted a new one but it was still the same. All through the summer it was fine but had a few coldish mornings lately and its started being sluggish to crank over. Its never failed to start so i just assumed it was something that they did and didnt view it as a potential problem till i read your post. I dont know how long you have owned your Roomster but did your problem start suddenly or has  it been  progressively worsening  ?

Hi Jeff . It used to play up, but I cured that at the re mappers and they deleted the offending items and been fine ever since until now, I have today noticed there is no more squishing noises from the in tank fuel pump like it used to , so have pulled it out tonight to take a look , It does look old and the original so may well be the problem. I'll bench test it and see what I've got , but at another £40/50  I might as well fit a new one while out. I do suspect this is the issue bit then again I thought that when changing the glow plugsthis week and the fuel filter , I expected a better faster response on here tbh . Everythings Brisk execept the replies lol . 

[JEFF-the-Bowman]

25 minutes ago, Jannercornwall said:

, I expected a better faster response on here tbh . Everythings Brisk execept the replies lol . 

Hi Jan .I dont know the reason ,but i guess its because there aint that many Roomster owners about 🙁

[Jannercornwall]

Well . Jeff . As your the only one listening or interested , I'll address you personally as no one else seems to give two craps . I have took the in tank fuel pump out and thoroughly cleaned it as it was covered in a black gunk, cleaned the strainer and checked the pump and re installed and the problem is still there , I may have to change the glow plug relay next as I am not sure the new plugs are getting any juice , Case of elimination by the looks of it till it's sorted , got a mate coming up soon with VagCom reader so hopefully that will shine a new light 

[JEFF-the-Bowman]

It dont help not having a workshop manual for the Roomster, but you seem very competent and mechanical minded John so i am sure you will find the problem in the end. You might also try heading over to the Fabia forum and asking there as i am sure someone said that everything at the front of a Fabia is exactly the same as the Roomsters

Good luck with your quest John

[CageyH]

Dragging this thread back up.

 

My colleague who has a problem with her 1.6TDi Roomster also has a 1.4TDi that does not start for her.

 

 

I went round to have a look. She tried to start it. The motor turns over, but will not start on just battery power. No codes were found in the ECU.

I popped my Noco GB50 booster pack on the battery terminals, and it immediately fired into life.

I removed the booster pack, the car starts fine.

 

My thoughts are to replace the Fuel pump/ECU relay. Do you think that is a good idea?

If so, where do I find it on an early Roomster?

[Warrior193]

Hello, I strongly suggest getting the battery tested first - I have seen quite a few reports of TDIs reluctance to start, only to see the problem fixed when the failing battery was replaced. It seems that some TDIs are particularly sensitive to slower than normal cranking speeds.

[CageyH]

I have left my colleague a multimeter to measure the battery voltage, and the booster pack.

I measured the voltage without the engine cranking and it was at 12.36. It dropped just below 12V on cranking.

I should have more info on Monday.

 

The battery was replaced 2 years ago by her local garage.

 

If someone can point me in the direction of gaining access to the relay panel, that would be great. The car is a 2007 1.4TDi 80BHP, if that helps. 

[Carlston]

5 hours ago, CageyH said:

I have left my colleague a multimeter to measure the battery voltage, and the booster pack.

I measured the voltage without the engine cranking and it was at 12.36. It dropped just below 12V on cranking.

I should have more info on Monday.

 

The battery was replaced 2 years ago by her local garage.

 

If someone can point me in the direction of gaining access to the relay panel, that would be great. The car is a 2007 1.4TDi 80BHP, if that helps. 

 

Is the 12.36 Volts measurement taken directly on the battery terminals? If you measure the Voltage at the cigarette lighter socket, the reading will be less than when measured directly at the battery terminals.

 

If the Voltage is 12.36 Volts measured directly at the battery terminals, then the battery voltage is too low.

 

I've recently got a new Varta (Silver Dynamic) lead acid battery, and 3 weeks after fully charging (using a Bosch fully automatic smart charger with a low 3.5 Amp charge rate) the voltage was still over 12.7 Volts without it being connected to the car or used. So with a good battery, the Voltage will hold up well even if it's not being used. If you've got a good battery, a car should still start even after 6 to 8 weeks of the car not being used.

 

Edited 23 February by Carlston

[CageyH]

When the car would not start initially, it was 12.36V at the battery terminals.

After starting it with the booster pack, and a 15 minute drive, it went up to 12.88V.

 

My colleague had tried to start the car several times during a two week period, hence the battery level being a bit low.

This is why I have asked her to try and start the car, and measure the battery voltage if it does not start, as I went to see if the battery is faulty.

[Warrior193]

What is really needed is a 'Cold Cranking Test' which measures the point the battery voltage falls to while turning over the engine - if the voltage falls too low, the battery will be unable to supply the necessary current (amps) to reliably operate the starter motor at the minimum speed required for the engine to fire - this would explain why the vehicle in question did start when the Noco booster pack was connected. Another point - while the starter battery is being subjected to the extreme current draw of the starter motor, other ancillary devices (fuel pump, etc.) will be affected by significantly reduced operating voltage. 

Edited 24 February by Warrior193
grammar

[CageyH]

There was no noticeable difference in cranking speed with the booster pack connected.

When I disconnected the booster pack, I did notice that the +ve battery terminal was a little “wobbly”, so I have fixed that minor problem.

[CageyH]

I guess a cold cranking test can be done by just measuring the battery voltage across the terminals while starting the engine?

What is the target voltage?

 

I would have spent longer troubleshooting, but the weather was not very good.

[Warrior193]

A loose or dirty terminal connection will cause a significant issue both in charging and starting performance. 

[Warrior193]

1 minute ago, CageyH said:

I guess a cold cranking test can be done by just measuring the battery voltage across the terminals while starting the engine?

What is the target voltage?

 

I would have spent longer troubleshooting, but the weather was not very good.

From memory, no lower than about 10.5 volts - the trouble with doing this test with a multimeter is that it is almost impossible to see what the DMM display is showing because it is changing so rapidly - even an analogue meter is very difficult to read under those conditions.   

[CageyH]

2 minutes ago, Warrior193 said:

A loose or dirty terminal connection will cause a significant issue both in charging and starting performance. 

Agreed.

This is why I did not want to replace the battery yet.

The garage where my colleague had the work done had visited the car recently because it would not start, after they had serviced it. They found no problem with it. The problem is that the garage is about two hours away from where she works.

 

My other thoughts are that one of the relays may be a bit tired, and the extra current available from the booster pack is (more than) enough to operate it. I will see how things progress over the following week, but I am looking at an AGM battery with a higher CCA than what my colleague has fitted.

 

The battery fitted is one typical of a “country” garage here in France. It is a brand I have never heard of, and I have my doubts over it’s capacity. My colleague told me that her problems started when the garage changed the battery. It could be that the terminal has been loose since then.

 

I hope my colleague will keep me informed over the weekend.

[Warrior193]

Is your colleagues' vehicle fitted with automatic stop-start? If so, EFB is the minimum required - AGM is best, but more expensive. What type is the current battery?

Was the replacement battery adapted (coded) when it was replaced?

If the incorrect battery type was fitted - and was not correctly adapted, this will almost certainly be the cause of the issue.    

[yeti12p]

Hi there,mine (2008 1.4tdi)does the same on frosty mornings but it normally fires after the second time i switch the key on.i have changed the battery(new correct one),the glow plugs and cleaned all connections for earth etc.I then bought a new starter motor as i think that is the problem but i have yet to change it(as i don`t like being cold .

Hope it helps.

[CageyH]

57 minutes ago, Warrior193 said:

Is your colleagues' vehicle fitted with automatic stop-start? If so, EFB is the minimum required - AGM is best, but more expensive. What type is the current battery?

Was the replacement battery adapted (coded) when it was replaced?

If the incorrect battery type was fitted - and was not correctly adapted, this will almost certainly be the cause of the issue.    

No start/stop as far as I am aware. I don’t think the battery was coded.

I will check. I was going to fit an AGM for the increased CCA capacity. For me, the higher the CCA, the better.

[J.R.]

13 hours ago, Carlston said:

If the Voltage is 12.36 Volts measured directly at the battery terminals, then the battery voltage is too low.

 

13 hours ago, Carlston said:

I've recently got a new Varta (Silver Dynamic) lead acid battery, and 3 weeks after fully charging (using a Bosch fully automatic smart charger with a low 3.5 Amp charge rate) the voltage was still over 12.7 Volts without it being connected to the car or used.

 

The first statement is incorrect because your battery in the second statement showing 12.7v on the bench would show only 12.36v on the vehicle with the bonnet open and the drain from all the awake canbus controllers, disconnecting the battery terminal would see it jump to 12.7v or higher.

3 hours ago, Warrior193 said:

What is really needed is a 'Cold Cranking Test' which measures the point the battery voltage falls to while turning over the engine - if the voltage falls too low, the battery will be unable to supply the necessary current (amps) to reliably operate the starter motor at the minimum speed required for the engine to fire

 

On that generation of TDi they had some stupid system that would not allow a cold engine to start below a certain cranking rpm and it wasn't voltage dependant, people were sometimes having to change starter motors rather than batteries or the better solution of having the function mapped out.

 

I agree that it starting with a jump pack means a new battery will probably have the vehicle starting but the underlying issue may be starter motor, cleaning all the starter and earth connections is a wise move.

 

The crazy thing being my TDIs of that generation without the dumb programming would start on one half of a lazy turn from a nearly dead battery.

[Warrior193]

1 hour ago, CageyH said:

No start/stop as far as I am aware. I don’t think the battery was coded.

I will check. I was going to fit an AGM for the increased CCA capacity. For me, the higher the CCA, the better.

You should be able to get all the CCA you need from a standard lead acid battery, especially if you fit the biggest option available, at a much reduced cost - or consider EFB.

[CageyH]

24 minutes ago, J.R. said:

 

 

The first statement is incorrect because your battery in the second statement showing 12.7v on the bench would show only 12.36v on the vehicle with the bonnet open and the drain from all the awake canbus controllers, disconnecting the battery terminal would see it jump to 12.7v or higher.

 

On that generation of TDi they had some stupid system that would not allow a cold engine to start below a certain cranking rpm and it wasn't voltage dependant, people were sometimes having to change starter motors rather than batteries or the better solution of having the function mapped out.

 

I agree that it starting with a jump pack means a new battery will probably have the vehicle starting but the underlying issue may be starter motor, cleaning all the starter and earth connections is a wise move.

 

The crazy thing being my TDIs of that generation without the dumb programming would start on one half of a lazy turn from a nearly dead battery.

Any idea of what the minimum cranking rpm is?

It is something I can check with my code reader, using the live data stream.

[xman]

Decades ago (1998-2001) when the 1.9tdi AFN was king of the hill, there was a known issue with minimum cranking speed. Can't remember if it was 170rpm but it seemed that some bright spark had programmed that as a requirement to start injection when starting the engine.

As starter motors became tired with commutator segments damage they turned over slower and the only remedy was to change the starter motor.

 

Not saying this is the case here

Edited 24 February by xman

[Warrior193]

On a Google search, I found an American website (VW TDI Discussion) that says minimum cranking speed must be greater than 200 RPM within 1 second of starter engagement.