[karan86]

Been a while since I gave back to this platform for all that I have learnt from here. So here goes...

Picked up a pre-owned 2017 Polo GT TDI in June 2023 with 78k kms on the odometer, from VW North Mumbai (previous owner upgraded) and have been bringing it up to speed, with an aim to keep it going for as long as I can, until the govt announces a sentence.



The car was in great shape when I bought it, with all service records intact. Thanks to all the contributions here from various members, I learnt that some preventive maintenance was on the cards. The suspension too was on its last legs and needed a change.


As soon as I got the car, changed the oil to Liqui Moly Top Tec 4100, along with all the filters, wipers, etc. The engine note transformed immediately and the car ran much smoother and a bit on the quiet side too. Have been sticking to a 10k km oil change interval ever since and I've emptied two bottles of Liqui Moly diesel purge in the tank till date.

At the 90k kms mark, the clutch had become too hard and made a creaky noise in the engine bay when the pedal was pushed in. Sent the car to the VW service centre to get the timing and accessories belt replaced, along with the water pump, clutch, flywheel, and tensioner. End result? The clutch felt super light post the change and I continue to not worry about any belt or water pump failure.



Right after, sent the car to Redline Autohaus for a suspension overhaul, brake pad change, and EGR & Intake cleaning. Akshay suggested the Bilstein B4s on stock springs after I shot down the B6s for being too expensive (very close to the 6 figure mark just for struts!). The B4s are a few thousands more than the Sachs I was after. Along with the struts, linkages, bushes, steering rod, etc were replaced. The result?

The car rides definitely on the firmer side (runs on Yokohama Earth 1s currently with another 10k kms life still in them. Michelins are up next) at slow speeds but doesn't crash violently into imperfections or potholes. The whole affair's rather European and mature.

However, once the speedometer climbs into three digits, the B4s come into their own and the car feels like it's on rails and flies a steady trajectory. Along with the steering rod replacement, it now feels eager to turn in, the steering has become more responsive and sends back amazing feedback. These B4s are aggressive on rebound and it is apparent when I'm the only one in the cabin and the left-side dampers thud back into their position during a climb down from a speed hump. Body roll is almost absent even when attacking corners at really silly speeds, and the chassis relays so much confidence through the seats and into my bosom, I've never experienced driving a Polo like this before! This is my second TDI (), and I was among the first to test the refreshed GT twins when they were launched and I was living life as a motoring journalist.


For those considering the Bilstein B4s, I would definitely recommend them, as long as you're okay to live with a firm ride at slow speeds. However, the benefits you reap when you drive enthusiastically, far outweigh that one aspect.


EBC or Brembo it wasn't available, so had to stick with OEM brake pads which aren't too bad but shed a lot of dust after a spirited drive. Cleaning the EGR and the intake manifold showed positive effects on the performance too.

However, I'm now dealing with two situations, for which I need inputs from the gurus here.


1) During one of the weekend drives, I noticed the engine temperature climbing up to 110 degrees, after a session of spirited driving, and would settle back to 90, quite immediately once I'd stick to speeds between 60 - 80 kmph. The first time it happened, there were three well-built individuals in the car, outside temp was 40 degrees, and the AC was on full blast. The second time I tried replicating it, I was the only one in the car, outside temperature was again 40, and the AC was set to 21 while I drove the car on some B roads, not overtly, but slightly enthusiastically.

Is this normal TDI engine behaviour? Because I'd never driven before with the display set to show the coolant temperature. I've also started noticing that when the temperature shoots beyond 100, the engine isn't as eager to rev as it does when the temperature's below 90. The coolant level is at the optimum mark and I haven't noticed any drop in levels. Air filter too is about 3k kms old and the car runs a cold air intake outlet.


2) The other problem I faced during one of the weekend drives was when the cabin started smelling of diesel (no check engine light) and upon opening the hood, figured that diesel was dripping down at the rate of a drop every second, at the ring where the switch/connector plugs into the common rail on the right hand side. Got a roadside mechanic to fix the leak with araldite and Mseal as per instructions from my trusty VW service advisor, and there's been no leak ever since.

Got the quick fix checked by an injector expert who knows his stuff really well. And after running diagnostics via the OBD, his suggestion - everything's working fine, there's no leak, no check engine light, the pressure is ideal, injectors are working well, and I'd suggest not fixing what ain't broken. Although I did push him to replace the common rail switch, he was hellbent that there's no need and I'd only waste money. I was floored by his honesty!

However, lately, the throttle doesn't feel as crisp anymore during not all but some drives, and some times, it feels like when I push the throttle in, diesel accumulates, and burns a second later, which is when the car surges ahead like I pinched its bum. This isn't regular behavior and I've been experiencing this on and off.

3) The headlight adjustment screws on top of the unit won't work and now the right unit's low beam is too low while the left unit's high beam points too much to the left. Is there any way to fix this? I am trying to avoid spending 20k on new sets which I know are rubbish anyways when it comes to illumination and I'm not a fan of LEDs.


I'd really appreciate some inputs as how do I go about fixing these issues. My goal for now is to restore factory performance, and get a Stage 1 remap once I know the components are okay to take that additional load. Although at 100,000 kms, will a remap make a difference? And if it's okay to, which one among Code6, Wolf, etc is a good bet?

Thank you for taking the time

[sachin_cs]

Originally Posted by karan86

However, I'm now dealing with two situations, for which I need inputs from the gurus here.
Attachment 2739107

1) During one of the weekend drives, I noticed the engine temperature climbing up to 110 degrees, after a session of spirited driving, and would settle back to 90, quite immediately once I'd stick to speeds between 60 - 80 kmph. The first time it happened, there were three well-built individuals in the car, outside temp was 40 degrees, and the AC was on full blast. The second time I tried replicating it, I was the only one in the car, outside temperature was again 40, and the AC was set to 21 while I drove the car on some B roads, not overtly, but slightly enthusiastically.

Is this normal TDI engine behaviour? Because I'd never driven before with the display set to show the coolant temperature. I've also started noticing that when the temperature shoots beyond 100, the engine isn't as eager to rev as it does when the temperature's below 90. The coolant level is at the optimum mark and I haven't noticed any drop in levels. Air filter too is about 3k kms old and the car runs a cold air intake outlet.
Attachment 2739098

Hi Karan, first of all, congratulations for your new beast, POLO GT TDI is one hell of a car and I’m so happy that you found such a clean example.

Coming to your query on coolant temperature, I have driven my Rapid TDI for 1.15L kms and no matter how I drive it, the coolant temperature has never risen above 90 C. The only time it went to 95 was when we were performing coolant flushing, that time the car was running on VW Coolant Flush kit, the liquid was provided by VAG itself, we did a 20km test run and that’s when the temperature rose but after cleaning the system and refilling with coolant, the temperature got back to normal. If it’s rising all the way to 110C, there’s definitively something wrong. You may want to check the followings-

• Coolant leakage
• Air bubble in the cooling system
• If water pump and timing kit replacement was done properly
• Correct Coolant Mix was used

Please update once you do the troubleshooting.

[karan86]

Thanks Sachin. It always stays at 90 within the city even after a couple hours of driving in jam-packed traffic. It’s only after a few hours of driving is when the temps shoot up. Trying to diagnose

[rejeen]

Originally Posted by karan86

It’s only after a few hours of driving is when the temps shoot up. Trying to diagnose

Just wondering if the fan is switching ON and/or the thermostat is woking fine to let the hot coolant circulate properly through the radiator to cool it down.

[anb]

Originally Posted by sachin_cs

Hi Karan, first of all, congratulations for your new beast, POLO GT TDI is one hell of a car and I’m so happy that you found such a clean example.

Coming to your query on coolant temperature, I have driven my Rapid TDI for 1.15L kms and no matter how I drive it, the coolant temperature has never risen above 90 C. The only time it went to 95 was when we were performing coolant flushing, that time the car was running on VW Coolant Flush kit, the liquid was provided by VAG itself, we did a 20km test run and that’s when the temperature rose but after cleaning the system and refilling with coolant, the temperature got back to normal. If it’s rising all the way to 110C, there’s definitively something wrong. You may want Please update once you do the troubleshooting.

In case of my remapped Polo 1.5 GT TDi, the MID always shows 90 degrees. But the obd reader shows different readings. Mostly the obd reading is around 96-100 degrees and it climbs up to 105 when climbing ghats or when pushing the car to the maximum.

[karan86]

Originally Posted by rejeen

Just wondering if the fan is switching ON and/or the thermostat is woking fine to let the hot coolant circulate properly through the radiator to cool it down.

It only happens when the car is pushed to the maximum or is being driven uphill at a slightly higher speed. Should I still get those things checked?

Originally Posted by anb

In case of my remapped Polo 1.5 GT TDi, the MID always shows 90 degrees. But the obd reader shows different readings. Mostly the obd reading is around 96-100 degrees and it climbs up to 105 when climbing ghats or when pushing the car to the maximum.

Maybe my car’s MID is as good as an OBD. Because it does climb up to 105 and 110 when pushed to the maxium or clinbing ghats enthusiastically. Things do stay at 90 during normal driving conditions.

Please share your experience post the remap if possible. Also, who’s the tuner?

[AKSarkar1]

Loved reading this post! As a fellow VW owner of the 6R family (Vento), I can totally see the efforts that it takes to maintain these cars like new.

For me at least, it makes total sense to spend on these cars and to keep them maintained because you simply don’t get such purebred European cars anymore. I just wish that VW makes their ASC more competitive and competent in the years to come, the moment they are absolutely horrible.

As for the headlights, I would suggest some high quality LEDs (even though you are not a fan), they have a very clear cutoff and do the job well even in a halogen reflector housing. If the LED quality is good + installation is done well then they will definitely not blind anyone on the road and will elevate your driving experience massively.

A remap at any stage of ownership would make a difference in the performance, I tend to share the unpopular opinion that remapping Polos and Ventos with the 1.2 TSI, 1.6 MPI have marginal gains but since yours is a diesel I would get a Stage 1 tune and stop at that. All engines have a running life, tuning without doubt makes that lesser since it puts more strain on the parts, your engine has already chomped through 1L Kms so I wouldn’t want to stress it beyond a stage 1 unless you are planning to make some hardware changes in the near future.

I hope you continue enjoying your ride well into the 2L Kms range!

[karan86]

Originally Posted by AKSarkar1

Loved reading this post! As a fellow VW owner of the 6R family (Vento), I can totally see the efforts that it takes to maintain these cars like new.

Thank you saar! Wishing you many more joyful miles with your 6R too. You’re right, will stop it at Stage 1 since that is all I need. The issue with LEDs is they need a proper housing. Unless that’s the case, I’d be only blinding oncoming vehicles and I won’t do what I don’t like done to me. Although I have found these Philips 3500 kelvin LEDs which are a straight fit. Still need to find a way to fix those screws on top of the headights which have slipped and the focus is haywire