1.2 HTP 44 kw BBM-wont start and missfire

[djordje48]

Few days a go, first problem after 10 years and 145 000 km without problems:) when cold in the morning, wont start at first time, it starts on second or third and then missfire and it tends to shut down. I have to press accelerator pedal to keep it working. After keeping it 1-2 minutes on 2000-3000 rpm, it starts to work ok. No problem during driving, I don't feel anything, but sometimes check engine lamp goes on and off. There were two errors: Camshaft sensor-I replaced new one. The problem continues after the new sensor (OEM from local dealer part). Of course, I changed spark plugs and checked ignition coils (no problem here). My aftermarket tool kit, Torque says P0141-System too lean.Went to local dealer service yesterday, he said that factory has new software for ECU-new software uploaded, but I have to come again to make optimization for some parameters, I don't understand quite, signal how engine works, how it mixes fuel and air, etc...Also, it can be fuel pump or dirty petrol jet system. I have LPG installation, but I also use petrol, car uses 40 litres of petrol every three months. I know that if you run LPG and forget about petrol, fuel jets and pump can go lazy...I don't suspect that powertrain chain can be problem (because of camshaft sensor). This problem keeps poping on on petrol, not on LPG. Everything is still original, chain, pulleys, etc...If someone has an idea in which direction to go, I will be thankfull:) In cases such as this, my first idea is to try to solve the problem with software (new ECU program, optimize parametars for engine work), and than to start to change the bad hardware (maybe jets need cleaning, maybe new petrol pump, maybe something else...) 

[Breezy_Pete]

Does it start OK once the engine is warm? 

If it does, consider whether the coolant temperature sensor may be giving bad readings.  Can you monitor the temperature sensor data with VCDS or similar to see if anything looks strange?

[djordje48]

Looks like the problem is even if the engine is warm. These days, temperatures are over 30C during the day and nights are hot, and the problem is also present. So, even on hot engine that works like 30 min, one hour, I leave it for one hour and the problem is again present...I can try that with this torque gadget, and I will see what the temp sensor says...It was 110C normaly during the work when hot...can it be the worst case, the engine leaks and false air-engine head gasket leaks??? it shouldnt be at this mileage...

[Rooted]

Maybe new fresh unleaded required if you still have in Winter spec petrol or older, maybe the inline fuel filter needs replacing, 

so many maybe's, 

what about the spark plugs, when were they checked or replaced, what about the coils?

EDIT, Sorry, i see you changed plugs and checked the coils.

Edited 22 August, 2017 by Awayoffski

[djordje48]

Yes, new plugs and three coils were replaced from my newer fabia (CHFA engine). And the problem is the same. Rubbish, this car has only weak point, the engine, it is sh.........t  :(    I mean, there is no single spot of corrosion after 10 years and the interior is intact, althought it carried a lots of junk, and I don't give a damn about keeping the interior or about scars on exterior colour. Gearbox still perfect. But the engine....for lawn mower, not for a car...:(

Edited 22 August, 2017 by djordje48

[mrgf]

Sounds similar to old carbed cars, when the choke was faulty!!!

 

Not sure if this is modern version of that problem... All vehicles need more fuel, etc to get warmed up. Problem with ecu and sensors is that many more things can go wrong. Check lamp could be problem with exhaust system. You say you replaced parts from newer car... Did you run the newer car on the older removed parts too, and if so, is it running ok? 

 

TBH, I think you are stumbling around in the dark, trying anything you can think of. At that age and mileage, why would you NOT expect a problem?  Exhausts, sensors, cam belts etc water pumps, in fact, many things could have failed by then. 

 

The reasoning of the car being good as its never gone wrong  has now flown out the window and you think its a pile of crap! I can't help wondering if you have neglected to maintain/service the car to manufacturers guidance.  You mention running on LPG, if this is running ok, have you got contaminated fuel in the petrol tank? When did you last run on petrol? It might be a good idea to drain the tank, change the fuel filter and putting in a quarter of a tank of quality fuel, as a starting point. Don't bother to fill up as you are just spending more for the same job a quarter a tank will do. 

[djordje48]

Well, this is spookey: the old camshaft sensor from my car gave an error in my car, but it does not give an error in newer car, it runs ok. The new camshaft sensor from newer car gives no error, but the problem persists like when there was old camshaft sensor. As I have said, new petrol (cca 40l) every three months, it has been like that for years. Every 15 000 km every filter changed and oil. New petrol filter just 10 days ago. Petrol RON 98, checked quality. LPG quality checked also, fuel is purchased at well known petrol dealers. Every 15 000 km LPG system checked, new filter and LPG ECU update. The car is heavy (weight) for 60 HP and runs desperately, but it is economical driving. This is how it works: I run LPG for 500-700 km (depends urban or extra urban autonomy), on LPG and than 15-20 km on petrol. And it has been like that since 18 000 km when I fitted LPG. In winter it is mostly run on petrol because sequent LPG system needs more time to warm up when started. These will be next steps: go once again to the dealers to optimize the parameters for ECU; after that check the engine compression. I will ask the code of error, they have official Skoda VAG diagnostics, I cant do that with my toy...

[xman]

Check the brake vacuum pipe for splits. Typically the ends split at the inlet manifold end and also the servo end. This allows air to be drawn in that weakens the mixture and cause symptoms similar to those you describe.

[djordje48]

Xman, thanks for hint. checked the hose, and one end was a bit loose. End that goes to engine. Sorted that, but no cracks on the hose itself. I dont believe this is the problem...I keep searching

 

http://imgur.com/a/NiHUN

[Breezy_Pete]

Compression test is a good idea, and checking the chain timing would be something I would do. 

Crank sensor is another possibility if those both seem OK.

[djordje48]

Xman, thanks for hint. checked the hose, and one end was a bit loose. End that goes to engine. Sorted that, but no cracks on the hose itself. I dont believe this is the problem...I keep searching

 

http://imgur.com/a/NiHUN

[djordje48]

Petrol jets were cleaned up and the problem is gone! Happy for sorting that out:)

[Jaguarv]

Hi Guys. I just bought my first skoda fabia 1.2, 55 reg. And i have have same missfire problem but basicly more specific... I called a "mobile mecanic" and paid £40 for a diagnostic check.... And showed him a cylinder 3 missfire... He then checked The spark plugs by changing them and also The coils. But The Code  for missfire cylinder 3 was still there... So he left... With £40 pounds and no answer what so ever what  The problem is...  He just said that i should get a electrician to check it out because it could be a bad wire or worse The ecu is broke/not reading data well. Please i beg you Guys help me i am s-o misrable and dont have a lot of money to fix it..  Whats The problem with The car!! Btw The engine shakes hard only goes upto 3000 rpm no Power whats so ever.. And engine Light on 

[xman]

Was the car running right when you bought it?

 

Did he fit new spark plugs (one or all three?) 

 

Did he fit a new coil (one or all three?) and in addition to the spark plug(s)?

 

Are you sure parts he fitted were new?

 

So does the car now have new spark plug(s) and coil(s)?

 

Did he change the plug/coil at the right side nearest the battery (looking toward the back of the car) or the left side?

 

 

[Jaguarv]

No he didn't  put New ones all he did was swap The sparkplugs between them by putting cylinder  sparkplug 3 to  cylinder 2 to see if The Code shows  different missfire cylinder... But it still stayed at cylinder 3  and he tryed The same thing with The coils and still showed cylinder 3......

 

Cylinder 3 is located on the gearbox side basicly The Last one to The right. 

[xman]

What a ******, not a mechanic!

 

Misfire codes do not clear by themselves straight away. They need to be cleared down otherwise they can take several restarts with no misfires to clear.

 

Its most likely a duff coil.

 

Buy a new coil from your local Eurocarparts, GSFcarparts or carparts4less, less than £25 using their discount codes. 

 

https://www.carparts4less.co.uk/ignition-coil

 

Start by replacing no 3 (if that is where he left the original no.3). If no joy then use the one you took off no.3 and swap with no.2. Try again, and of no joy, swap no.1 with the one you removed from no. 2

 

When starting the car, let it run for several seconds and rev it as it sometimes takes several seconds to clear the spark plugs.

 

Spark plugs are only £3 each so treat it to new plugs (a t bar plug spanner is less than a fiver).

 

https://www.carparts4less.co.uk/spark-plugs

 

Coil failures are common, so recommended to carry a spare.

 

If none of this helps you need to move on to the fuel injectors.

 

At this stage a code reader will help, Carparts4less do good code readers from about £17

 

Google Streetwize OBD II reader

Edited 10 December, 2018 by xman

[Jaguarv]

God i hope your right.... Just seems like lost cause. that mechanic really killed my optimism.. And The worst part i dont know if he swaped The plugs or coils back to their place.. 

 

 

[xman]

You didn't say when you bought the car if it was running right. If it was faulty when you bought it, it could be something more serious.

 

Was it a private sale or a trader/garage/dealer?

 

If it was a trader/garage/dealer they may be responsible under Consumer Rights Act to fix it.

[Jaguarv]

I just bought The car 4 Days ago from a private seller.... The car was in the Same state... He told me its just a sparkplug.. I saw The right  syptoms... So stupidly i belived him... 

Worst decision ever... But it couldnt be  my foult entirely right? I mean i just The normal syptoms of a blown sparkplug... Had one with a audi... So just seem normal to me  and The Guy look decent. 

[rum4mo]

This is easy for me to say now, but, if I was selling a car that was quite old, so not getting much money for it, and it was running rough, I would have sorted that out so that I could get the best money for it and not have someone coming back and knocking on my door and complaining that I had just ripped them off - like what seems to have happened to you!

 

It does sound a bit like injector issue as coil and plug seem to have been checked by swopping, I am guessing that while you have not said this, that your mobile mechanic would have cleared logged faults before restarting the car after the coil/plug swops, I'm sure that he was not that stupid?

 

Good luck!

 

Edit:- being decent looking is a useful asset to have in the selling cheap cars business world.

Edited 11 December, 2018 by rum4mo

[J.R.]

Even if he was not able to clear the fault codes by swapping the suspect components a new fault code would have been generated for the next cylinder if they were faulty.

 

So I dont think he was being stupid, its possibly a communication error through repeating what was thought to be said, his diagnosis is plausible and he knows it now needs someone with specific knowledge, experience and diagnostic equipment.

[rum4mo]

18 minutes ago, J.R. said:

Even if he was not able to clear the fault codes by swapping the suspect components a new fault code would have been generated for the next cylinder if they were faulty.

 

So I dont think he was being stupid, its possibly a communication error through repeating what was thought to be said, his diagnosis is plausible and he knows it now needs someone with specific knowledge, experience and diagnostic equipment.

 

I agree in the situation where a spark plug or coil turns out to be the root cause of the problem, but the smart money is surely on performing a 2 minute read/clear logged faults before restarting the engine after each swop.

[Breezy_Pete]

A compression test might be worth doing.

[Jaguarv]

Today i Will try and change The injector... If that doesnt work... I will start selling it because its just not worth my time and energy...  Thanks Guys for The support and help. If you have any more tips or know The problem so i can fix it please reach out! 

[xman]

If it was not a spark plug or coil but an injector, or certainly something serious like wrecked valve gear or low compression, then the seller grossly misrepresented the sale, i.e. lied blatantly about the real  fault. So technically he committed fraud, and you could pursue a small claims from him, best to confront him first though, after you have the facts.

Edited 11 December, 2018 by xman