[wooka]

Team, thanks for your help! The problem persist but I have a few to-do's at my end.

Originally Posted by Aroy

It is either loose contact with ignition coil, or clogged fuel filter. Get both checked.

Ignition coil is fit! Fuel filter was changed a week back. Problem persisted.

Originally Posted by hserus

Fuel pump / pump relay? Ignition coil?

Fuel pump is good (my car hits highway speeds easily).
Ignition coil again seems to be fine - the RMP dropping to 0 minus mild forced aceleration cannot link to weak ignition coils per my SA.

I've got this done:
1. Sprayed down the throttle body in-place (as a jugaad @ AS$). SA said that if the situation improves (can only be tested properly on a cold engine), then the throttle body needs proper cleaning.
2. I've taken a spare relay to swap with the fuel pumps and ignition relay tomorrow as part of troubleshooting.

Anything troubleshooting tips would be appreciated!
Is it worth cleaning the MAF/O2 sensor? I mean, this is an ignition only issue, but if I am suffering performance-wise elsewhere, I wouldn't know since I just got my hands on this vehicle.

[hserus]

Originally Posted by wooka

Team, thanks for your help! The problem persist but I have a few to-do's at my end.

Just follow Jeroen's advice a few posts earlier and have your SA plug in an OBD-II scanner, search for errors.

[wooka]

Originally Posted by hserus

Just follow Jeroen's advice a few posts earlier and have your SA plug in an OBD-II scanner, search for errors.

Agreed. I shall get on it tomorrow!

[Aroy]

I older petrol cars it would be Vapour Lock, but in a diesel car that is not the case. All that is left is to check the fuel lines for clogging and or kinks.

I suggest that you also get the compression checked both in a cold engine and in a hot engine, as low compression will not start the engine. The causes for low compression in a hot engine are many.

[Jaggu]

Originally Posted by wooka

Agreed. I shall get on it tomorrow!

If you give accelerator input and crank, is the car starting? And will it hold the rev with accelerator input?

If so, clean the throttle body and check if the idle advance circuit is working as it should.

[great_guns]

Originally Posted by Jaggu

If you give accelerator input and crank, is the car starting? And will it hold the rev with accelerator input?

If so, clean the throttle body and check if the idle advance circuit is working as it should.

Would you suggest the same for my problem?

[Jaggu]

Originally Posted by great_guns

Would you suggest the same for my problem?

Not really. I would rather pursue the mystery below, especially if the error is coming back after clearing it. Do get the tank cleaned also.

hooked up to service center scanner and found 2 error codes (G40 CAM sensor and G28 engine speed sensor).

Replying from phone. I’ll take another detailed look from the computer and share thoughts if I have further inputs.

[Jeroen]

Crankshaft and or cam shaft sensors are known to cause problems for starting on many cars. You would think this type of sensor works or doesn't work. However, in practice I have seen problems just on starting and idling due to wonky sensors. These are most often induction type of sensors, so the faster the engine runs the more stable the signal is likely to get. Of course, the idea being that the sensors provides a stable enough input even during low rpm.

I would start by carefully inspecting the sensor and its wiring and clean the connectors, see if that makes a difference. Workshop manuals might provide the correct test values, if not you might just want to try to swap.

[Jaggu]

Apart from cam sensor, internet search says temperature sensor, weak starter motor also causes the issue with the older tdi engines. So temperature sensor is also a good place to check further if the engine is turning over well when hot.

[Jeroen]

Originally Posted by Jaggu

Apart from cam sensor, internet search says temperature sensor, weak starter motor also causes the issue with the older tdi engines. So temperature sensor is also a good place to check further if the engine is turning over well when hot.

Yes but it would have shown up at an OBD scan and it did not.

Jeroen

[Jeroen]

The temperature sensor that is

[Jaggu]

They say it will not show any errors, but once you replace the sensor it will start fine even when warm. This is an engine specific phenomenon.

[great_guns]

Originally Posted by Jaggu

They say it will not show any errors, but once you replace the sensor it will start fine even when warm. This is an engine specific phenomenon.

That sounds interesting. So you reckon the CAM sensor and engine speed sensor errors might not be the direct cause?

Can we rule out vapor lock as a reason completely? It's a 2.0 TDi engine (2007 build)

[Jaggu]

Originally Posted by great_guns

Can we rule out vapor lock as a reason completely? It's a 2.0 TDi engine (2007 build)

Vapour lock in a diesel, I doubt so. That phenomenon is more focussed on petrol engines and the carb engined cars, more than fuel injected / electronic fuel pumps.

[Exhaust_Note]

My Santro (84K KM old) has developed one issue. During the drive to KK I had replaced the 12V Mobile Charger with a branded one as the local one was causing the fuse to be blown once too often.

No more issues with the fuse now. But after about 200-250 KMs of non-stop running, the charger connected at all time to the GPS Phone, I stopped the car and it refused to start. The cranking was happening but the motor was not offering in return. Battery was OK, all lights and horn was in full strength. But as I cranked the engine, it was just trying to catch it and then missing it. Push start worked.

I panicked and removed the charger. After a couple of 100 KMs, dared to stop and restart and all was fine. On the way back, the same happened again but no charger this time and after a few long cranks and pressing the accelerator, it started on itself (no push required).

A little back ground: The car, since I acquired it has a late start tendency. I mean when friends who own cars try to start it, they feel they have to turn and hold the key longer than they are used to.

My thoughts say it may be a old and worn starter motor. Any help and direction would be appreciated. May be old spark plugs? But the car is serviced at Bosch (Pragati Motors, Varthur) and Kuldeep the SA, has a free hand regarding genuine repairs as far as approvals etc is concerned. Am quite satisfied with the services done. So I guess these things may not be the issue.