Car feeling choppy after using fuel injector cleaner.

[Nads02]

After a couple of months of driving my yaris I noticed at idle the engine seemed to shake, very slightly and randomly. Thought nothing of it but it seemed to be getting worse.

So i thought about it for a long time, and was thinking I serviced it recently, so maybe not the air system (filter changed) and 4 spark plugs were changed too (didn't torque it but did it until snug, didn't go crazy). I thought it was the fuel system, and I suspected the injectors.

At the petrol station I found a fuel injector cleaner for petrol engine for £5. Thought it's worth a shot or I'll have to dig in a bit deeper. What a mistake that seemed to be. Seems the engine is shaking even worse. I don't know if it means it's working or my engine is s***ing itself. Even going down the a2 (at the speed limit) at 50mph the engine seemed choppy.

I don't even remember the brand or the bottle. I remember smelling it (to see if I got scammed to pay £5 for 350ml of petrol) and it smelled like a number 2. It also said it treats up to 50 litres. My car has 45 litre fuel tank so I emptied the entire bottle into my car. Maybe I shouldve paid more attention to what I was doing.

As it stands right now, I got about 300 miles until my tank is empty. Should i wait until the my fuel is nearly empty to see if it's ok? And would it have caused any damage? What's your experiences of fuel injector cleaners? I'm a bit worried about this as I'm super broke at the moment and can't really afford any sort of repairs until I get paid. But should I be worried?

[Tony1963]

It needs looking at by a competent car mechanic. There are too many variables to sort this on line. It could be fuel quality, a broken wire, fuel filter.. the list could go on.

[steveo3002]

good chance its something else , coils or plugs

has it been serviced properly ?

[GreenV8S]

It sounds as if it's got a misfire. You need to get the problem sorted out by a competent mechanic. It may well be something simple and cheap to fix. However, if you keep driving it like that you're likely to destroy the cat, if you haven't already.

[Nads02]

Had a further poke around the engine and found a little bit of oil in the 3rd and 4th cylinders spark plug wells. Decided to put everything back and take it to my trusted mechanic. He mentioned it could be running weirdly because if the oil gets in between the spark plug and ignition coil it won't work properly. He wiped the oil out and it has improved much more. I'm thinking maybe I might have used the wrong oil? I used 5W30. Maybe I should use a thicker oil. My mechanic told me its most likely the rocker cover gasket and to come back in a week. Hopefully after a new rocker cover gasket and 4 spark plugs my little yaris is going to be happier!

[Arnie Cunningham]

My old motorbike used to leak oil into the spark plug cavity, eventually causing that cylinder to misfire. A quick clean and all was good again, hopefully yours is the same. I even had the gasket replaced, but 12 months later it was doing it again. So I just used to make cleaning it part of the service.

[Nads02]

Arnie Cunningham said:

My old motorbike used to leak oil into the spark plug cavity, eventually causing that cylinder to misfire. A quick clean and all was good again, hopefully yours is the same. I even had the gasket replaced, but 12 months later it was doing it again. So I just used to make cleaning it part of the service.

Since cleaning the oil out the engines been running much smoother. Occasionally I feel the odd shake but it's very rare. I'll check it again next week on Wednesday. But I'll start scraping together a few pennies to change the gasket soon!