misfire only when cold

[triple j]

Well lads I have a slight misfire. Its only when started from cold then it clears after a few seconds, the car has being sitting up a few years I have fresh petrol in and it should be going through the system at this stage as it was well low before I topped up, my fear is stem oil seals but I don't get any burned oil smoke, any ideas, new sparke plugs in also

[starletezy]

Could be your water temp sensor. That plays a part in controlling fuelling on cold start and on hot when they fail they usually cause misfire on cold starts and when hot

[triple j]

Thanks lad that's something to look at.

[Stu]

It could be the water temp sensor but to be honest I have only had to change one in all the time ive worked on Toyota engines, instead I'd start with the basics like checking the leads/cap/rotor are ok. A corroded terminal inside the dizzy could be causing weak spark which with the extra post start/warm up enrichment could be blowing the spark out. Saying that though in my experience of tuning cold start and warm up enrichment, miss fire is usually due to lean running conditions, overly rich mixtures just make the engine bog and die rather than miss.

[triple j]

Thanks for the reply Stu,the car has being sitting in storage for 6/7 years, only thing I did was change the plugs out for new ones and also gapped them, am thinking it could still have some bad petrol in there, I need to get it out for a good drive but before that I will check the dizzy and other ignition related.

[5e colin]

could be worn engine to a valve not seating propperly etc etc

[triple j]

Na i had a look in with a bore scope the next morning after I posted this and all looked well, the small bit of 6 year old petrol might be it, its clearing, good service and a driving may do.

[starletezy]

Might need a good service by the sounds of it