Time for the cambelt replacement?

chroniclesofcf

Active Member
Mar 3, 2022
52
12
28
Paisley, Renfrewshire.
Noticed when foots flat to the floor in 3rd and above at about 2500-4000rpm, there is random dips in power. You can feel it come and go. Like it drops from 180bhp (it's remapped) to 125bhp and back a couple of times till it gets about 3.5-4k revs.

Someone mentioned it might be the cambelt. Took some pictures. What do you think? Time for a replacement?

Any other ideas what it could be? Dirty fuel filter. Do I even have one? Injectors? Spark plugs?

Cars a 2018 1.4TSI SC FR. Done 111k miles. No previous history before me so taking it as it's never been changed. Did the water pump about 6 months ago. Due a service now as well.
 

black_sheep

Active Member
Mar 10, 2013
1,256
585
Need to plug it into a diagnostic tool (one that can read the VAG codes, not a basic one).

Could be any number of faults, but the diagnostic tool will get you to the right ball park.

If it's overdue a service then do this first. Oil, filters and spark plugs if you doubt they've been done. The workshop manuals are available here (look for the one titled maintenance):


I would very much doubt that the cambelt is causing the issue you describe, but replace if it's due; these tend to be more catastrophic modes of failure.

Could be the clutch slipping, a sensor that measures airflow or controls boost failing, flat spot in the map.
 
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chroniclesofcf

Active Member
Mar 3, 2022
52
12
28
Paisley, Renfrewshire.
Need to plug it into a diagnostic tool (one that can read the VAG codes, not a basic one).

Could be any number of faults, but the diagnostic tool will get you to the right ball park.

If it's overdue a service then do this first. Oil, filters and spark plugs if you doubt they've been done. The workshop manuals are available here (look for the one titled maintenance):


I would very much doubt that the cambelt is causing the issue you describe, but replace if it's due; these tend to be more catastrophic modes of failure.

Could be the clutch slipping, a sensor that measures airflow or controls boost failing, flat spot in the map.
I have a Carista obd scanner. Would that suffice?

No lights on the dash I should mention.

Last service was about 10 months ago which was about 13k miles.

Now you mentioned it, I did have a weird, what's felt like, intermittent clutch slip. It happened for like 2 days then disappeared and hasn't been back since. That was 5 months.

Gonna get it booked in for next week.
 

chroniclesofcf

Active Member
Mar 3, 2022
52
12
28
Paisley, Renfrewshire.
PXL_20230513_081534432.jpg
PXL_20230513_081525066.jpg
PXL_20230513_081520368.jpg

Pictures of the cambelt btw.
 

black_sheep

Active Member
Mar 10, 2013
1,256
585
I don't know the 1.4 engine that well to be honest. Most of my knowledge is on the 2.0 petrol & diesels and 1.9 diesels.

Carista should be ok.

I've seen this previously with the N75 boost sensor starting to fail, but not sure if this is fitted on the 1.4?

Also, if the MAF (mass air flow) sensor gets dirty it can provide incorrect readings.

Both of the above can cause power issues as they impact air/fuel ratios, thus power.

Is the car manual or DSG?

If manual you can check for a slipping clutch by applying handbrake and trying to pull away in 2nd/3rd gear with handbrake still applied - if the car stalls, clutch should be ok.

If DSG, the map may produce torque in excess of what the gearbox can handle. Might be possible to tune the box with increased clamping pressure, but think that the dry clutch in the 1.4 can't handle loads of torque.
 
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chroniclesofcf

Active Member
Mar 3, 2022
52
12
28
Paisley, Renfrewshire.
I don't know the 1.4 engine that well to be honest. Most of my knowledge is on the 2.0 petrol & diesels and 1.9 diesels.

Carista should be ok.

I've seen this previously with the N75 boost sensor starting to fail, but not sure if this is fitted on the 1.4?

Also, if the MAF (mass air flow) sensor gets dirty it can provide incorrect readings.

Both of the above can cause power issues as they impact air/fuel ratios, thus power.

Is the car manual or DSG?

If manual you can check for a slipping clutch by applying handbrake and trying to pull away in 2nd/3rd gear with handbrake still applied - if the car stalls, clutch should be ok.

If DSG, the map may produce torque in excess of what the gearbox can handle. Might be possible to tune the box with increased clamping pressure, but think that the dry clutch in the 1.4 can't handle loads of torque.
I'll plug it in when I get back and see if anything pops up.

It does seem the 1.4TSI has an N75 sensor. Not sure if it's specifically the EA211 though. The twin charged EA111 does.

It's a manual. Stock clutch and gearbox. Not sure of it's history before me. So it could be original clutch. Map brought it from 125 at the crank to 180 Dyno'd. Torque up to 285 I think.

It's an e-brake so I wouldn't be able to do that would I?
 

chroniclesofcf

Active Member
Mar 3, 2022
52
12
28
Paisley, Renfrewshire.
I don't know the 1.4 engine that well to be honest. Most of my knowledge is on the 2.0 petrol & diesels and 1.9 diesels.

Carista should be ok.

I've seen this previously with the N75 boost sensor starting to fail, but not sure if this is fitted on the 1.4?

Also, if the MAF (mass air flow) sensor gets dirty it can provide incorrect readings.

Both of the above can cause power issues as they impact air/fuel ratios, thus power.

Is the car manual or DSG?

If manual you can check for a slipping clutch by applying handbrake and trying to pull away in 2nd/3rd gear with handbrake still applied - if the car stalls, clutch should be ok.

If DSG, the map may produce torque in excess of what the gearbox can handle. Might be possible to tune the box with increased clamping pressure, but think that the dry clutch in the 1.4 can't handle loads of torque.
So, tried slipping the clutch in second with the handbrake on. It does stall. Pedal felt maybe a little long but definitely stalled.
 

chroniclesofcf

Active Member
Mar 3, 2022
52
12
28
Paisley, Renfrewshire.
Plugged in the carista to check for errors too. This is what I got back.
 

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mty12345

Active Member
Jun 17, 2011
3,728
451
bristol
The cambelt can't cause intermitant issues, but it looks horrible from what i can see in the pics! Also the position of it in the first pic is very weird! i was trying to work out if it was a camera angle, but it looks like its almost come off the back of the pulley?? Is it tensioned properly? It should be fairly tight and you shouldn't be able to slide it back and forwards.

I'd get it looked at/changed ASAP.
 

RUM4MO

Active Member
Jun 4, 2008
7,784
983
South Scotland
I've noticed that the cam belt does not sit in the centre of both these cam shaft pulleys on my wife's 2015 VW Polo 1.2TSI 110PS, so I've put it down to a design error, regardless of where the cam belt or new cam belt is initially located on these pulleys, when the engine is turning, the belt will move into what is the "best" position for it, which probably means the position that reduces its tension to the minimum for it, just logic in my mind.
 

SuperV8

Active Member
May 30, 2019
1,320
581
The cambelt can't cause intermitant issues, but it looks horrible from what i can see in the pics! Also the position of it in the first pic is very weird! i was trying to work out if it was a camera angle, but it looks like its almost come off the back of the pulley?? Is it tensioned properly? It should be fairly tight and you shouldn't be able to slide it back and forwards.

I'd get it looked at/changed ASAP.

This is just the angle of the photo I believe.
The one pulley on the EA211 looks like its twice as deep as the other pulley.

1684750385702.png
 
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