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Old 1st March 2017, 18:16   #1
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Default Heavy petrol smell on cranking

Okay a weird problem happened recently on my Alto K10 AMT. Everything was as usual - it went for the usual daily office drive and back on a Friday and didnt see much action on the weekend (Saturday). The car has done about 13K km in its 1Y4M life and has been regularly serviced at company specified intervals - pretty much a run of the mill standard fare vehicle.

Sunday evening, I wanted to take it for a spin and started the car. It cranked fine and even started but I immediately noticed that it was choking - the engine didnt reach its initial healthy cold start RPM of about ~1100-1200 and was sounding like a coughing and sputtering block at ~600 rpm and after about 5-10 seconds, it died. Naturally, I waited for about 30s before trying to start it again and this time, I get the crank but the engine is not starting. Again, I wait 20-30s and crank again - I hear the crank and starter motor - but engine does not come to life.

By this time, I am getting a heavy smell of petrol fumes within the cabin. To be safe, I roll down the windows and try cranking it again - nothing. More smell.

I wait for about 2-3 minutes and try cranking again, this time, bonnet was open. Also, I ensured that I held the key at the IGN crank position for a longer duration and the engines is going "kharr kharr khaaarrrr khaarrrr" and finally it comes to life after a brief sputter. I press the A pedal to get the engine revving and now, the engine dies again.

Wait 2-3 minutes again and try with the long crank and this time, I didnt press the A pedal - just held the crank until the engine came to life and now, the engine sputters to life and after 5 seconds or so, gets to its good cold start idle RPM of about 1100. I keep the engine running and use the time to connect my phone to the OBD Torque Pro App. By the time the app opens, pairs with the OBD device and shows me realtime info, the engine has settled to its idle RPM of about 750. I quickly run a scan of error codes and dont see anything. I took the car for a spin and still, it was behaving as if nothing was wrong.

Next day, I took the car to the A*S*S (it worked fine like usual) and even they checked the issue and couldn't find fault. Now, the car is running fine and its almost like nothing ever happened! To be on the safer side, I got the Air filter cleaned and other fluids checked out as the ASS and everything was put back - nothing was amiss except for a moderately dirty Air filter which they said was pretty common.

Can someone let me know what happened here? Is this something I should be worried about? I'm mostly concerned since Im the type who switches off the engine at traffic signals >60-75s and not being able to start the car at a signal would mean hell in BLR rush hour traffic - and I would also probably have to search for a twig/leafy branch of a tree to attach to my car in traffic - warning people that a vehicle is broken down (forget the warning triangle!)

Any insights into this would be useful!
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Old 1st March 2017, 18:24   #2
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Default re: Heavy petrol smell on cranking

Very difficult to pin point but it could be a momentary issue with the fuelling system, maybe some blockage in the system causing petrol to flow into the de-canister which is there to comply with emission norms.

Did you check the fuel filter? and was the fuel filled from the usual petrol station the last time around?
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Old 1st March 2017, 18:26   #3
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Default re: Heavy petrol smell on cranking

You're smelling unburned fuel.

I hope you aren't depressing the accelerator whilst starting. Never do that with MPFI engines. Next time try starting without depressing the A pedal. Also, don't continuously crank the engine. You will foul the spark plugs and run your car battery down.

If this doesn't work check the ignition system starting with the spark plugs and HT cables. Make sure all spark plug caps are fitted securely on the plugs.

Last edited by R2D2 : 1st March 2017 at 18:28.
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Old 1st March 2017, 21:43   #4
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Default re: Heavy petrol smell on cranking

Quote:
Originally Posted by vsathyap View Post
Okay a weird problem happened recently on my Alto K10 AMT.
...
Can someone let me know what happened here? Is this something I should be worried about?
Any insights into this would be useful!
Fuel injected petrol engine flooding and refusing to start up is not a common problem, but can happen.

Two possibilities about what happened here:
1) One (or more) of the injectors were stuck in open position, perhaps due to muck in the fuel line; or
2) The intake oxygen sensor was faulty (loose contact or temporarily shorted out), causing the ECM to overfuel the cylinders.

Ideal remedy would be to open up and service all the injectors, clean & flush the fuel lines and tank (including the tank suction end filter), put in a new fuel filter, check the oxygen sensor contacts, and maybe replace the oxygen sensor. Even though you may be covered under warranty, I doubt if the MASS would agree to do all this as long as the car is running okay while with them.

But since your car is running fine at the present moment, you could just clean out the tank and fuel lines, put in a new fuel filter, add an injector cleaner to a full tank of petrol, and clean and refit the oxygen sensor and its electrical contacts. After this, give your car an Italian tuneup while you take your family for a long drive! Fingers crossed, the problem should not recur.

In case flooding happens again (i.e. if you smell petrol and the car refuses to start), floor the throttle and crank the engine - the ECM is programmed in all cars to shut off fuel supply to the injectors, if the sensors detect a wide-open throttle while the engine turns over below idling speed. The engine will then fire up for a short while and burn off the excess fuel, or clear up the excess fuel through the exhaust valves.

Last edited by SS-Traveller : 1st March 2017 at 21:46.
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Old 2nd March 2017, 21:20   #5
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Default Re: Heavy petrol smell on cranking

Quote:
Originally Posted by Jaggu View Post
Did you check the fuel filter? and was the fuel filled from the usual petrol station the last time around?
I didnt get the Fuel Filter checked - and yeah I always fill up at 2 bunks near my house; its either Shell or HP and both bunks are good in terms of quality and quantity.

Quote:
Originally Posted by R2D2 View Post
You're smelling unburned fuel.

I hope you aren't depressing the accelerator whilst starting. Never do that with MPFI engines. Next time try starting without depressing the A pedal. Also, don't continuously crank the engine. You will foul the spark plugs and run your car battery down.
Ideally, its not recommended that I do this - specifically on my AMT where my right leg needs to be depressing the Brake Pedal and the Car should be in "N" to be able to crank the engine. I do however press the A pedal ever so lightly after the engine comes to life - just a blip to the throttle. I may have subconsciously done this multiple times while cranking the engine and while it failed to start. I didn't however depress the A pedal fully or knowingly - this is for sure.


Quote:
Originally Posted by SS-Traveller View Post
Fuel injected petrol engine flooding and refusing to start up is not a common problem, but can happen.

Two possibilities about what happened here:
1) One ...fuel line; or
2) The intake oxygen sensor ....fuel the cylinders.

Ideal remedy would be to open up and service all the injectors, ....car is running okay while with them.

But since your car is running fine at the present ....Fingers crossed, the problem should not recur.

In case flooding happens again .... clear up the excess fuel through the exhaust valves.
Woah - this is some seriously awesome Technical Advice!!! No wonder TBHP is such a loved community! Am sure the MASS guys didn't bother to take even 1% of the effort that you took to type those words in here!!!

Yes I agree with the replacement of fuel filters etc. of the problem recurs. And regarding the flooring of A Pedal during start, the post above yours tells me not to press the A Pedal on MPFI engines while your views are totally opposite (or I didn't understand one of you guys correctly). What's the right thing to do?

And yes, regarding the Italian tune-up - I just love to do it once every 3-4 months. I take it on a longish drive where the engine gets to stretch its legs . I am a firm believer of this and have seen it work wonders on my old and new K10s. Moreover, the FE I get after this tune-up is really awesome; though it creeps back to its abysmal levels after driving in city conditions after a week or so.

Will keep the thread updated if I sense more cranking issues. So far, its behaving as though nothing has happened.
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Old 2nd March 2017, 21:31   #6
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Default Re: Heavy petrol smell on cranking

Quote:
Originally Posted by vsathyap View Post
Will keep the thread updated if I sense more cranking issues. So far, its behaving as though nothing has happened.
For now just get the fuel filter checked and replaced if need be, it is not an expensive thing to do. Most likely it was a momentary block somewhere in the lines, would have cleared itself out for all we know.

Yes in electronic systems there are over rides that take care of excess fuelling unlike carbs.

Plugs, plug wires and coil pack are the other things you can get it checked, just to be sure.
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Old 2nd March 2017, 21:55   #7
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Default Re: Heavy petrol smell on cranking

I am having somewhat similar issues with my Swift 1.2 K-Series.

Few days back I noticed this petrol smell during start up just after cranking. Happened for like 2-3 days continuously. It used to happen with my F10D WagonR too sometimes, so I didn't give it much of attention.

But yesterday at around 4 PM when I started the car after it was parked for 7 hours under the scorching sun, it started with engine idling at just 500-600 rpm which was rather unusual. I thought the engine would die but then just after a couple of seconds the revs shot up to 1500 rpm. The car drove perfectly fine. Next day morning, i.e. today, the car cranked like it always used to be, settling at around 1500 rpm which is its usual for cold starts.

But then same thing happened when I started the car at 4:30 PM after around 7 or 8 hours of parking. Initial revs after cranking at around 500 rpms after which it shot instantly to 1500 rpms.

Will check what happens tomorrow. The car in question is a July 2014 model and covered just 20K kms with fuel filter never changed till now as Maruti recommends changing it at 40K kms.

Last edited by GTO : 3rd March 2017 at 13:40. Reason: Typos
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Old 2nd March 2017, 22:21   #8
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Default Re: Heavy petrol smell on cranking

Quote:
Originally Posted by Sherlocked View Post
Few days back I noticed this petrol smell during start up just after cranking. Happened for like 2-3 days continuously...
Quote:
Originally Posted by vsathyap View Post
.... It cranked fine and even started but I immediately noticed that it was choking - the engine didnt reach its initial healthy cold start RPM of about ~1100-1200 and was sounding like a coughing and sputtering block at ~600 rpm and after about 5-10 seconds, it died. ...
Usually it is the lambda sensor which when faulty throws up these symptoms. However, if so, it will show up in an OBD Error code check. May be it was a temporary wiring issue.

Do keep checking the Error Codes once in a while though.

If you do end up with a flooded engine, follow SST's advice. Pedal to the Metal.
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Old 3rd March 2017, 00:29   #9
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Default Re: Heavy petrol smell on cranking

Quote:
Originally Posted by vsathyap View Post
...regarding the flooring of A Pedal during start, the post above yours tells me not to press the A Pedal on MPFI engines while your views are totally opposite (or I didn't understand one of you guys correctly). What's the right thing to do?
Quote:
Originally Posted by dhanushs View Post
If you do end up with a flooded engine, follow SST's advice. Pedal to the Metal.
As dhanushs also pointed out, wide-open throttle at starting is a method to use only when you are sure the engine is flooded. With WOT the engine won't fire under normal conditions.

Even with AMT, you can press the brake pedal with your left foot while pressing the A-pedal to the floor with your right foot. The engine will still crank.
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Old 3rd March 2017, 08:42   #10
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Default Re: Heavy petrol smell on cranking

Quote:
Originally Posted by Sherlocked View Post
I am having somewhat similar issues with my Swift 1.2 K-Series.
... when I started the car after it was parked for 7 hours under scorching sun, it started with engine idling at just 500-600 rpm which was rather unusual.
It's caused by vapour lock in the fuel rail.

Turn on the ignition and wait about 10 seconds before cranking. The fuel pump should be able to clear up the vapour by then, and your engine should fire normally without faltering.

And do get the fuel filter changed, and the fuel pump delivery pressure checked.
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