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Old 21st July 2009, 14:19   #1
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Question Getz: Low RPM misfire

Hi all,

This happened to me over the weekend, going to Banaglore. My Getz 1.3 was cruising along happily on the GQ till i slowed down at the Ranipet tollplaza when I noticed vibrations at idle, i opened the doors and thought that silencer has probably gone bust with a small hole.

The vibrations disappered at higher RPMs and there was no significant loss of power. But more than half way thru, I noticed that the fuel guage was going down faster than usual and the plastic casing around the handbrake was very hot. The idle speed vibrations only grew stronger and louder at each tollplaza stop.

I got down to check and couldn't feel any air escaping the sliencer but noticed the exhaust note was more like one cylinder missing/misfiring. Thought that the problem could be due to a engine-braking manuvere which could have taken the RPM to beyond redline. We decided to reach bangalore and have the car checked.

After battling Hosur road traffic, Took the car to Trident Hyundai at Sheshadripuram and they thought it must be a electrical problem. The computer indicated no errors in the ECU though! The spark plugs and cables were fine. By now driving in slow speeds was a hassle, especially in the steep inclines around Sheshadripuram.

Decided to leave the car with them for further diagnosis and returned to Chennai. The service advisor today discovered that there was rust in the fuel tank, and a particle is blocking the injectors and hence the mild misfire in one of the cylinders and catalytic converter was overloaded with unburnt fuel and overheated and probably damanged permanently. This also explains why the misfire disappered in higher rpms.

Now in a car that is only 2.5 years , is rusting possible, or is it due to the crud coming from the petrol station? I've always fueled up at Balakrishna bunk at St Mary's road Chennai, quite a popular bunk. I fill the tank when it reaches close to the empty mark.

For now i've asked Trident Hyundai to clean the tank, lines and injectors to get the car back on road. Do I really need to spend Rs7500 to replace the tank now? Any advice, past experiences and such are welcome.
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Old 21st July 2009, 23:38   #2
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now since your cat is destroyed. get a free flow then youll be able to keep up with and beat swifts.
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Old 23rd July 2009, 20:53   #3
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That's a great idea Akshay. But I'd wait till my warranty expires in a year and half.

Got the car back from Bangalore and the injector cleaning and tune up was great. Felt like a new car, it gave me a whole new gear.
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Old 24th July 2009, 17:45   #4
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How did it get past the fuel filter? That's what filters are for. I feel there's some misinformation here. I have had various cars for seven years, never had a problem with rust in the fuel tank. My last Hyundai Santro was with me six years.

More likely a fuel pump and injector issue. They should replace everything under warranty.
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Old 25th July 2009, 12:01   #5
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When i asked him about the same, he insisted that fuel filter can only handle so much!! I still don't buy that story entirely. Also they didn't change the fuel pump or injectors, only the fuel filter.

They firmly believe it is a case of bad fuel, and i don't think the tank itself is rusting, more likely the fuel from the bunk was contaminated. Since I wasn't there in Bangalore to verify the state of the tank, fuel filter and injectors, I guess I have to accept their story.
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Old 25th July 2009, 13:03   #6
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Do a complete tank, fuel line and injector clean up and fill in fresh fuel. Check for emissions after this, maybe after you run for 100 kms or so. Your car should be fine.
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Old 25th July 2009, 19:21   #7
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Jaggu, Trident Hyundai charged Rs.1700 for fuel filter replacement and tank, lines and injector cleaning. After a full tank of fresh fuel, the car runs very smoothly even at very high RPMs. I have to check on the emissions.
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Old 9th September 2009, 10:38   #8
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Guys,

I am having a similar misfire problem in my Getz.

Few days back, my car was parked in level 2 parking in my office and due to heavy rains,
water had entered the parking and my car was standing in water upto almost 1.5 - 2 feet
water for about 20 hours. The water had raised above the silencer level.

I had couple of AMPs beneath the seats and those got damaged.

Anyways I had given the car for service and cleaning the very next day and they drained
the tank completely, cleaned the injectors and did the regular service. They also said there
was no rusting or anything seen under the body.

Now though I dont see any shudder or loss of power but sometimes in low
rpms I see misfiring happening sometimes.

Please let me know if I can continue to drive like this. The misfiring does not happen
always but sometimes and I can live with it. However I would like to know if I would
make a permanent damage in the long run.

If I need to rectify the misfiring problem, let me know what all I need to have checked.

Thank you.

Last edited by drvhplyevraftr : 9th September 2009 at 10:39.
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Old 9th September 2009, 11:23   #9
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Quote:
Originally Posted by PraveenM View Post
Jaggu, Trident Hyundai charged Rs.1700 for fuel filter replacement and tank, lines and injector cleaning. After a full tank of fresh fuel, the car runs very smoothly even at very high RPMs. I have to check on the emissions.
Hi Praveen

Upto what RPM you find the engine smooth? I am asking because my Getz 1.3 is now 4 months old and has done almost 5000 km. Upto 2500 RPM it is very silent and the feel is very smooth. I find the engine feel quite rough and noisy by the time it hits 3000 RPM. I rarely do that (city driving mostly) but once when I went till 4000 RPM in 1st gear, it was really very noisy. Is this abnormal? If so, I will mention this during my 2nd service

thanks
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Old 13th September 2009, 20:56   #10
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Duplicate Post, Could some mod please delete this

Last edited by dipen : 13th September 2009 at 21:01. Reason: duplicate post
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Old 13th September 2009, 20:57   #11
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Duplicate Post, Could some mod please delete this.

Last edited by dipen : 13th September 2009 at 21:01. Reason: duplicate post
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Old 13th September 2009, 20:58   #12
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Quote:
Originally Posted by mohan41 View Post
Hi Praveen

Upto what RPM you find the engine smooth? I am asking because my Getz 1.3 is now 4 months old and has done almost 5000 km. Upto 2500 RPM it is very silent and the feel is very smooth. I find the engine feel quite rough and noisy by the time it hits 3000 RPM. I rarely do that (city driving mostly) but once when I went till 4000 RPM in 1st gear, it was really very noisy. Is this abnormal? If so, I will mention this during my 2nd service

thanks
2nd service will surely smoothen out the noise (just a little though) and the car would be a little more free revving. Getz engine is not very free revving like the i10. But it still a very competent car.

The noise is prominent and not very pleasing in the Getz ( compared to Suzuki and Honda).

Could you answer :
Quote:
Originally Posted by dipen View Post
What is the recommended tire pressure in the GLS. (175/70/R13). On a friend's car, I felt 30 psi on the lower side. I think, it could do with 31 or 32.

What are the RPM readings in 5th gear while cruising at 80, 100, 110, 120, and 130 speeds.
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Old 14th September 2009, 14:15   #13
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Quote:
Originally Posted by dipen View Post
2nd service will surely smoothen out the noise (just a little though) and the car would be a little more free revving. Getz engine is not very free revving like the i10. But it still a very competent car.

The noise is prominent and not very pleasing in the Getz ( compared to Suzuki and Honda).

Could you answer :
On my GLX (it has 175/65 R14) the recommended pressure is 30 for single occupant and 33 when fully loaded. I keep it 32 usually.

RPM in 5th gear: I remember its around 2800 at 100kmph (approx), and around 1600 at 60Kmph. I havent taken it above 100 so far. You can calculate it using the gear ratio data and tyre size.

Gear Ratio
1 3.61
2 1.95
3 1.37
4 1.06
5 0.82
Final drive ratio: 4.056
Tyre size for my car (GLX) = 14 + 175*2*0.65/(2.5*10)

Speed at 3000 RPM 5th gear
= RPM*3.14*2.5*TyreSize*60
------------------------
(4.056*0.82)*100*1000

If you the reverse of it, you get the RPM at different speeds. For GLX it comes to around 2500RPM for 80kmph, 3000RPM for 100kmph etc.
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