Now, That's a Man: Pre-Worshipped Maruti Suzuki SX4 ZDi (Rebuild & Ownership Review)

[bhvm]

There was a little bit of power drop after mid rpm (probably due to high return

Hmm. This needs to be looked into.

My doubts with using injector cleaner is how to get the IMA code after cleaning

Just don't mix them.
And put them where they were.
Write numbers or put small colored stickers on them...

 

[VISHNUCARCRAZY]

Yes bro, am using double clutching only.

 

[Auto_Psycho]

Just don't mix them.
And put them where they were.
Write numbers or put small colored stickers on them...

No no that's not what i am asking!.
That code printed on the injector is only valid until the first injector service. After servicing the injectors, the calibration will change completely, and a new code will be generated according to the performance of each injectors. We have to manually feed these new codes to the ECU according to the cylinders ( the process is known as Injector Coding). So the ECU can control the fuel delivery precisely.
In that sense, using a fuel injector cleaner is only a temporary solution, isn't it?

 

[Auto_Psycho]

Cleaning Interiors
Purchased 3M interior cleaner from Amazon (512 Rs).It works like magic!

Test result

Before

After

It cleaned everythings inside the car pretty well, except for the water stain mark in the rear seat.
Have to try deep cleaning another time..

Replacing Trunk Room Lamp
Costs: 39 Rs

Replacing Gear Knob and Boot
Gear Knob (Ciaz)-390 Rs
Boot- 205 Rs
( I replaced the gear lever assembly too, sorry forgot to take pics)
Gear lever assembly costs 1020 Rs.

Now, the gear shifts smoothly like a brand new car!
I forgot to mention that, after grinding the plastic gear inside steeeing rack with valve grinding paste, the steering feels so smooth and the sticking issue is completely gone!!

I am really enjoying the turns now!!

 

[VISHNUCARCRAZY]

Use white silica grease on Shift lever linkages, it makes it butter smooth.

I also love 3M interior foam cleaner, it works so well.

 

[blu_7760]

What are the symptoms of broken rocker arms??
Why would it break by itself in the first place??


It would have remained hidden if not for this diy.

rocker arms breaks if you do not follow tightening / loosening sequence. Cam shaft too can break in two pieces if sequence is not followed. again all this can happen if you try to push start these mjd engines.

 

[mayankdixit]

rocker arms breaks if you do not follow tightening / loosening sequence. Cam shaft too can break in two pieces if sequence is not followed. again all this can happen if you try to push start these mjd engines.

Thank you. I did not know that. But are you suggesting that this is what happened in the OP's SX4 ?

 

[Auto_Psycho]

Sorry, haven't been able to update this thread as I've been busy with my work...
Here is the rest of the story...
Even after rebuilding the engine and cleaning the catalytic converter, the performance of the car did not feel good to me.. No problem at low RPM, but near 2500–3000, the engine seems to lose power, like something is choking the engine.
It seems like a clogged catalytic converter.
Driving with a clogged catalytic converter can damage the turbo and the engine severely, I don't want to take that risk.
So I removed the catalytic converter again to check it thoroughly.

Previously, I checked the cat with water, but at that time it looks like it's in okay condition.
This time, I used a leaf blower and a piece of paper to check the catalytic converter.
(Place a small piece of paper near one end of the catalytic converter and use a leaf blower to blow air from the other side. If the catalytic converter is severely clogged, the paper will not fly away.)
When I checked my catalytic converter, that piece of paper didn't even move a little.
So it is officially confirmed that the catalytic converter is clogged..

Now I have 4 options in front of me:

1. Buy a new catalytic converter. ( costs a huge amount.)
2. Buy a used catalytic converter. (It costs less, but I don't know how long it will last.)
3. See if the catalytic converter can be cleaned.
4. Remove the catalytic converter.(But emission test will fail)

The first two options are too costly and a little risky, so I don't want to jump into any of them immediately. Removing the catalytic converter in today's conditions may not be a good idea for my pocket.

So i decided to go for the third option first..
But I don't know whether it will be successful or not. But thought I'd give it a try.
For that, first the catalytic converter was filled with diesel and left overnight to let the carbon agitate..

(Taking photo of the catalyst is very difficult in this car, but somehow I managed to take some snaps.
You can clearly see the clogged holes..)

Then in the morning, I gave the catalytic converter to a water service station and asked them to clean it with diluted caustic soda and a pressure washer..
The service shop guy filled the cat with diluted caustic soda and put it aside for 10–15 minutes. Then use the pressure washer to clean the cat.
Here are some pictures of what happened next:

The floor of the service station was completely filled with carbon, and it takes around 4 to 5 rounds of washing to completely clean the catalytic converter. Caustic soda has done a fantastic job of removing the carbon deposit inside the catalytic converter.

Before

After

After cleaning, i tested the cat again with leaf blower and the test was passed successfully.
Then I installed it back into the car and on the initial test drive, I could clearly feel that difference.
The engine is so relaxed now, and the engine is revving easily to higher rpms without any hesitation..

Lesson learnt: Never do anything without double checking and making sure.

To be continued...

 

[Auto_Psycho]

Installing Steering Wheel Covers
Since this is my first steering wheel cover stitching, i decided to go for the cheap one..
Price: 210

Result

Replacing Windshield Wipers
The size of the windshield wipers of SX4 was
D-26
P-14
But I didn't see wipers from brands like Bosch and Valeo of this size online.
So finally, I ordered an unbranded wiper set that had good reviews.
Price:580

Old one was Bosch make

New one named Power X

Excellent wipe, and for this price range, these wipers are just great!!!

 

[Auto_Psycho]

Unexpected Problems
A few days ago, when I was driving home, the car's engine turned off suddenly!
I turned off the ignition for a few seconds and then tried to start the car again.
This time, the car started without any issues. But after a few kilometres, the engine shuts down again..
When I turned on the ignition again, I noticed that the low-pressure pump inside the fuel tank was not humming!
So it is almost confirmed that the issue was somewhere related to low-pressure pump.
But the problem here is that in sx4, the fuel pump was not easily accessible, like in Beat!
We need to unmount the fuel tank from the car to access the fuel pump, and that can't be done on the roadside.

Luckily, after a few 'ons and offs, I heard the humming sound of the pump again.
So I tried to crank the engine, and the engine started without any hassle.
Then I drove the car slowly towards my home, and I successfully managed to reach it without any problems.
That night, I tried to dig up any useful information regarding this issue online and found out that this is a common problem in many SX4's, and the issue was with the fuel pump wiring.

See the same issue was mentioned in @ManIsBack's thread: Fuel Pump Problem in SX4 Diesel Celebration.
So the next plan is to unmount the fuel pump and check what's wrong with the fuel pump. But before that, I checked the basic items like the fuse, fuel pump relay, and wiring harness. Everything seems okay..

I hooked up a bulb in the fuel pump wiring from the fusebox to the rear passenger side seat to check if the wiring was taking loads properly, and it was okay.

Its getting dark, and I am so tired now to do further digging, so I decided to postpone the job for another day.

Next Day
With the help of my "disinterested" assistant (brother), I removed the fuel tank from the car.

After removing the fuel pump wiring harness, I found out what caused the fuel pump to die!

The fuel pump connector was melted, and this was the culprit! Don't know why it keeps happening to SX4's.

Anyway, now there are only two options:
1. Buy a new fuel pump which costs near 10K
2.Connect the fuel pump and float's wiring directly to the wiring harness.

As this old pump was working fine with good pressure, I didn't want to waste that much money for nothing.
So I disconnected the wiring from the fuel pump and float to the connectors, soldered them directly to the wiring harness, and safely insulated them.

I did a final check inside the fuel tank before installing the fuel pump assembly, and everything looks ok.

Then I mounted the fuel tank back into the vehicle and checked the pump, and it was working fine.
Since it was the weekend and I had a lot of time, I planned to have the injectors serviced.

But when I took the diesel filter off, I was shocked! The filter was completely clogged and crushed (probably due to suction from hp pump). But only 10K kilometres have passed since the filter was changed!
Also, there was a small diesel leak from the fuel filter assembly and due to that, the filter assmebly was completly covered in dust.

Here's what I think is the cause of the mysterious problem with the fuel pump wiring harness on the SX4:

-The fuel filter clogs much faster than the company says (thanks to the quality of diesel in our country).

-Due to the clogged filter, the stress on the fuel pump increases.

- Maybe the leaking issue with the fuel filter assembly was also due to this clogged fuel filter. Imagine that the fuel pump was pumping diesel into the filter, but due to the clogged filter, the pressure inside the fuel filter assembly increased, causing the leak.

-As the stress increases, the pump draws more current.

-If the pins on the pump wiring harness are not tight when the pump draws more current,the connector's pins may overheat and melt down the plastic pieces.

to be continued...

 

[mayankdixit]

Here's what I think is the cause of the mysterious problem with the fuel pump wiring harness on the SX4:

-The fuel filter clogs much faster than the company says (thanks to the quality of diesel in our country)..............If the pins on the pump wiring harness are not tight when the pump draws more current,the connector's pins may overheat and melt down the plastic pieces.

That's a very fine and systemic diagnosis you made. Job very well done !!
Unmounting and taking out a fuel tank, that too when it filled (half ?) with diesel is no small task. How did you accomplish that ?
That pic of inside the fuel tank is very interesting. How did you capture that ?

 

[Auto_Psycho]

That's a very fine and systemic diagnosis you made. Job very well done !!

Thankyou..

Unmounting and taking out a fuel tank, that too when it filled (half ?) with diesel is no small task. How did you accomplish that ?

No, there was only a quarter tank of diesel left in the tank. However, getting this large tank off is a bit of a challenge.

That pic of inside the fuel tank is very interesting. How did you capture that ?

It's easy; once we remove the fuel pump assembly, we have a big enough gap to take detailed photos.

 

[Auto_Psycho]

CRDI Injector Servicing Explained
Before entering into my story, let me explain what should be done while servicing diesel injectors in modern cars.
Diesel injectors are not as simple as the injectors found in regular petrol cars.
There is an accurate measurement of how each injector performs (how much diesel is injected into the cylinder (aka delivery) and how much goes back to the tank (aka Return)).
But this may not be the same for all injectors. The delivery and return will vary with each injector. That means even if we buy four new injectors, their delivery and return will vary.

But if there is such a variation in the delivery, it will affect the power, mileage, and smoothness of the car.
To avoid this, each injector is assigned with a code called as Calibration code. This code represents how that injector works (like how much diesel is being delivered at idle,high rpm, and so on).
Many manufacturers call this code by many names, but the concept remains the same.
For example, in Bosch/Siemens, it is called the IMA code;

in Delphi, it is called the calibration code.

This code will be fed into the car's ECU by the step called Injector Coding. By doing so, the ECU can understand exactly how the injectors in each cylinder are performing. Through this, the ECU will be able to adjust the injection of diesel to each cylinder accurately.
The problem here is that, when we disassemble the injector and service it, in some cases there may be variations in the delivery of the injectors, and if there were any variations in the delivery, the calibration code printed on this injector will not be valid anymore.
According to the current delivery, a new calibration code will be generated in the testing machine. The injector coding should be performed with that new calibration code.
These are the important things to do while servicing the injector of a diesel vehicle.
Now let's get into the story. I removed the injectors from the SX4 and gave it to a famous diesel service shop nearby. They told me that they would check the injectors and call me back. The next morning, they called me and told me that they checked all the injectors, and three of them were very weak, and the fourth injector was completely out of delivery!!
They told me that they couldn't believe how this car was running without such a low delivery.
In short, I was running on three cylinder the entire time!!
Anyway, the biggest problem right now is that just cleaning the injectors won't fix my current problem. Since the delivery of all four injectors is very weak (which is a clear indication of a worn-out control valve and nozzle), I need to replace the control valves and nozzles of all injectors too.
It costs approx. 6,000 per injector!!

Parts inside an injector (for clarification)

In such situations, we have three choices.

1. Buy new injectors (which cost around 65K).
2. Check that the old ones can be serviced (in most cases, the injectors can be serviced, but in some cases, even if the service is done, the delivery will not be proper; in such cases, the injector should be replaced).
3. Go for used injectors. (Costs around 4K per injector)

Here, I decided to service the injectors. It costs around Rs 30,000, but its main advantage is that, if serviced and maintained properly, the injectors will perform and last as well as brand new injectors at half the price. But the biggest headache I experienced here was explaining this to the people at that diesel service shop. No matter how much I explained to them, they do not agree that the IMA code (calibration code) may change during the service.
After a lot of arguing, I finally showed them a video from YouTube of generating a new IMA code after servicing the injectors. After watching that video, those were arguing with me shuts their mouth.
They told me that they never heard of it; none of the local shops around here do it, and none of them have the equipment to do it.Then they gave me the number of Bosch's authorised service centre in Kottayam and told me to contact them. The name of that shop was Sreemuruga Diesels. I contacted them and explained my situation. They listened to me in detail and answered all my questions very clearly. I really liked the way they handled customers, so I decided to have my injectors serviced there and sent the injectors via parcel to sreemuruga.
After checking the injectors, they asked me the same question: How come this car has been running without any problems with these injectors?

They kept me updated through WhatsApp while the injector was being serviced. Hats off to the entire crew at Sreemuruga Diesels Kottayam, especially to the guy named Rajesh, who answered all my questions accurately despite being so busy.

Here are some photos they shared
The first bar indicates the delivery and second bar indicates return of the injector. The red color means the delivery was too low.

'IMA identifier' shows the current IMA code of the injector.
See the red 3 dash (---) in below the ima codes? The new IMA code will generated at that place instead of that red dashes.. But here, the delivery of all four injectors is very bad so the new IMA code is not generating.
Around 16 different tests has to be performed on each injectors before reaching this result!

Injectors after servicing.
See the IMA code was generated, but you can see that there was no change in the IMA code. That's because the delivery of all 3 injectors remains same as manufactured.

But when it comes to the fourth one (the dead one), you can see that after servicing, the IMA Code was changed. Because there was a slight change in the delivery.

Costs 29592Rs for Injector Servicing!

Recieved injectors on the very next day!
New Nozzle!

Adding a little bit of grease to the body of the injectors to prevent rust welding in the future

After replacing the fuel filter, I installed the injectors back and man o man the feel of the vehicle was totally changed!!
NVH level was decreased, Acceleration improved a lot and the sluggish feel was completely disappeared.
Engine revs easily without any lag.
Now there is one more thing to do and that is 'injector coding'; Only after doing that, the process of injector servicing can be said to be complete.