[bala80]

Hello All

I have a problem to which i need some advice from you all. I own a swift VDI which has done about 9500 Km. Recently i gave it for 10k Service and when i checked on the performance of the car post service, i found that the surge of turbo at around 2000 rpm was missing and the acceleration was more linear. I complained about it and the technician hooked up the diagnostic tool to the ECU and showed me the reading of Boost pressure. If i recollect it right, it was around 101-102 psa (i hope the unit is right) @2000 RPM and around 120 psa @3000 RPM. To validate my complaint we checked the same data in another VDI which had done around 40k Km and the boost pressure was almost the same as mine (marginally lower by 1 or 2 psa). I was still not convinced and i asked them to replace the air filter with a new one. It was also done and now the results are a little better. The surge does happen, however with less vigour and at around 2500 RPM. There is no turbo leakage suspected, No issues with accelerator sensor, air pressure is maintained at 32F and 30R (all these suggested for a similar issue reported previously). I need to also make a note that my old air filter was not terribly bad or anything and it was in a OK condition. Can you help me understand the problem here a little better and any pointers towards resolution would be greatly appreciated. Thank you for your time.

Regards
Bala

Note from Mod team: Copying posts from my long term review, since many members have been reporting this as an issue with Swift Diesel engines.

[Jaggu]

@bala80: check the engine oil level after overnight parking, if its more than full mark, reduce the oil level.

I run higher pressure of 34 and 32 psi on F & R tires.

Been having similar problems as bala. will update once the problem is solved.

[bala80]

Thanks for your response Jaggu. I have checked on the oil level and looks to be fine. Also, i would want to add that there is the feeling of surge only under hard acceleration in 2nd and 3rd gears. I used to feel it even under moderate acceleration before, however now that is not the case. Also the vigour has definitely gone down considerably. I have all through my ownership maintained the same tyre pressure and hence dont think thats contributing to my issue. I run 185/70/14 on stock rims.

Ripper - I'm waiting for your suggestions. Thank you.

Originally Posted by Jaggu

@bala80: check the engine oil level after overnight parking, if its more than full mark, reduce the oil level.

I run higher pressure of 34 and 32 psi on F & R tires.

Originally Posted by bala80

Ripper - I'm waiting for your suggestions. Thank you.

The MASS I have given the car to are looking at all things possible. I have been told that the sensors were replaced one by one, and the car test driven,
I dont know the results of that exercise yet.

Things found so far
1.MAF sensor was dirty- cleaned with carb cleaning fluid at MASS, and blow dried with pressurised air- no improvement.
2.Wire running from MAF sensor was found to be cut- replaced- no effect
3.Throttle position sensor changed- no effect
4.Turbo- visually inspected- small amount of carbon/soot which washed off with petrol- made things worse
5.Tech2 connected which showed normal amount of boost
I didnt believe that result- so I hooked up a boost gauge and drove the car- only 2PSI boost made at 2000rpm progressively climbed to only 11psi at 4500rpm so I'm suspecting the turbo, should I?
(note-the car makes 2psi boost even from 1200rpm, which seems to be a bit too much for that level of rpm, because normally the DDiS is dead in the water till 2000rpm).
6. wastegate checked-
It is a mechanical wastegate- and is still set at factory settings. the screw is painted in orange at the right level, so if that had changed we'd be able to see it.
I still got it checked, and it seems to be functioning properly,cracking open at 15psi and wide open at 21psi., but that was when it was taken out and checked, so I dont know if it is functioning well while it is actually in the engine.

Almost all the VDis I have driven have a later onset of boost than when the car is brand new. It would be good to know if other members on tbhp are experiencing the same. Boost should kick in without any subtlety at 2k rpm dot, or in some cars, slightly earlier.
Note- that only VDis have tachos, so only VDi owners will be able to pick up the problem.

Initially, when my boost started coming later at around 2.2k I put it down to the hard run in I gave it, and I was actually not worried, because my lag was practically gone, but over the last year the boost has come later and later and finally ended up at 2.6k rpm. Even now, the low end response is pretty impressive(1000-2000rpm) compared to a brand new swift, but there is no response beyond that. I suspect the turbo.

The car is not smoking heavily. mileage is around 16 in city with Ac still.
Should I look at the clutch? Not sure! Maybe it is slipping when the peak torque kicks in. Car revs beautifully still(almost too beautifully). Not sure if it is revving effectively though.
Still in the process of looking, so will let you guys know what is happening.

My theory on the clutch- it is slipping as torque comes in, therefore releasing the engine from load, therefore boost is not building. Can someone confirm if this halfbaked theory holds good?

On second thoughts, I'll tell them to look at the clutch too.

[Eddy]

Ripper, does the delayed boost happen in all gears ?

Edit: In 5th gear, without the AC, what speed are you at 2000 rpm ?

Originally Posted by Eddy

Ripper, does the delayed boost happen in all gears ?

Edit: In 5th gear, without the AC, what speed are you at 2000 rpm ?

Same as always- around 80 I think, just that it takes much longer to get there.The RPM speed relation would stay constant wouldnt it? that depends on the gear ratios.
Delayed Boost happens in all gears. after the turbo was cleaned, even that has gone, and there is no perceptible boost at all.
behaves like it's normally aspirated.

Ok, I get what you're thinking of- clutch slippage would mean a rpm speedo mismatch-Got it! So its not the clutch, Sigh! I was really hoping that it was the clutch.

EDIT- BTW, there is no oil seal in the turbo, so if the oil is overfilled, I guess it could get in to the all sorts of unwanted areas inside the turbo. maruti has issued a circular to all MASS places to fill only 2.9 liters if filter is not being changed and 3.1 liters if filter is being changed. seems that there were plenty of turbo problems/damages because of overfilling engine oil.

[Jaggu]

@rippergeo: Clutch can be a culprit, second would be fueling since you complain of smoke.

Anybody with turbo boost data of ddis? please post up. Are you sure about the external boost gauge reading, if they are authentic?

One more thing, did you try complete reset of ecu in stock set up?

[mtnrajdeep]

My car has run 5400 km till now and after the second service, even I am observing that the boost is at 2.2k rpm now. I just feel the boost building up slowly at 2 k rpm. At the MASS, air filter, engine oil level were checked and every thing was normal. The tyre pressure I am running at is 36 in front and 33 at the rear and the mileage that I get is around 17 in city outskirts. Daily run is only about 25 km.

The car is a VDi ABS.

Originally Posted by Jaggu

@rippergeo: Clutch can be a culprit, second would be fueling since you complain of smoke.

Anybody with turbo boost data of ddis? please post up. Are you sure about the external boost gauge reading, if they are authentic?

One more thing, did you try complete reset of ecu in stock set up?

I think the external boost gauge is right. it correlates well with seat of pants dyno. Its an Autometer gauge, and was installed by professionals not by me

Had totally forgotten about ECU reset,even though it was part of my initial checklist. thanks for reminding me.

Smoke is actually far less than what the car used to make when it was new. So may be fuelling too, but tech 2 seem to show that normal amounts of fuel were being injected, but I dont know what the normal numbers are, and I doubt if the well meaning MASS guys have a clue. They said fuelling is good, I had to accept because I have even lesser knowledge about that part of things

I do have the service manual for the fiat 1.3mjd in PDF which was kindly provided to me by drpullockaran, but have not had the time to go through it yet. This weekend maybe.

EDIT@mtnrajdeep- thanks for that info.
anyone else with late boost?

[bala80]

Jaggu - Im fairly confident about the accuracy of the numbers that i had posted before and it was measured using the diagnostic tool at MASS hooked upto the ECU. I also remember that the idle boost pressure was pegged at around 98 (im sorry, i think the unit was psa, however i might be wrong here). My car wasnt smoking excessively and is behaving absolutely normal otherwise. As Ripper has described in his post, under moderate acceleration there is no perceptible difference, and im feeling a little boost only under very hard acceleration and only in 2nd and 3rd gears.

Ripper - Thank you for your inputs and appreciate your efforts here.

Originally Posted by Jaggu

Anybody with turbo boost data of ddis? please post up. Are you sure about the external boost gauge reading, if they are authentic?

Bala- I think there will not be any boost produced at idle. Unless the car is in gear and under some
load. I'm not sure what sensor the tech 2 uses to read boost pressure. Can someone clarify.
The external boost gauge and tech 2 gave widely different readings in my case.

Compression of individual cylinders checked yesterday via the gap for heater plugs, everything's ok. phew

[bala80]

Ripper - The A/C was on and the car was idling at around 900 RPM. It was not in a gear though. If any of our team members happen to visit MASS with their VDI/LDI, i would request them to check for the boost pressure statistics and post here. My MASS doesnt have an iota of idea as to what the issue here could be, im following your inferences as it looks like both of us are facing exactly the same problem. Thanks Ripper.

Originally Posted by rippergeo

Bala- I think there will not be any boost produced at idle. Unless the car is in gear and under some
load. I'm not sure what sensor the tech 2 uses to read boost pressure. Can someone clarify.
The external boost gauge and tech 2 gave widely different readings in my case.

Compression of individual cylinders checked yesterday via the gap for heater plugs, everything's ok. phew

[Jaggu]

Try escalating the issue to the regional service head of Maruti through your M.A.S.S, i think they will be the right people to diagnose the issue further.

Though with my limited knowledge check points can be:

• Fuel quality check
• Air filter and plumbing
• Turbo/inetrcooler plumbing
• Oil level check
• Accelerator sensor check/clean up
• Diesel filter check
• Common rail pressure check
• ECU check
• Turbo health check
• Compression check

[F50]

Originally Posted by bala80

Ripper - If any of our team members happen to visit MASS with their VDI/LDI, i would request them to check for the boost pressure statistics and post here.

Today, I gave my Vdi for 15k service actually 16k, I have asked him to show me the stats using tech2? or some other name he gave i forgot. I will post it around 7pm or so.

Anything else needs to be checked? let me know.