Question about 1998 Toyota 4Runner

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Car idles and runs ruff until 2500 rpm then smoothes out. Scanner says problem with cylinders 6 & 3. replaced coil but problem still persists.

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Hi the problem could be with the leads going to the spark plugs, it could also be spark plug faults, so as you have changed the coil it may be worth getting a set of plugs and leads and replace them to rule out any of them being at fault, then the next thing to do would be to go out and buy a decent fuel line cleaner.

Make sure you buy correct type ie petrol or diesel then follow instructions on back of bottle, how ever it will say pour this into a full tank of fuel, now dont do this pour it into half a tank of fuel this will make it work a lot quicker and you will then get better results.

once you have poured it into the tank do the following.
1, drive steady for 15 to 20 min
2 then drive a bit harder such as pulling away faster and taking the revs up higher
3 then drive normal for the last 15 min doing this will ensure all fuel lines are clean and also injectors are cleaned, this will also remove any carbon build up on the valves so using this alone could solve your problem.

it just sounds like you need a good service so have a look at plugs and leads then try the fuel cleaner, you can buy the fuel cleaner from most filling stations and car spares shops a good brand to buy is called Red X

let me know how you get on or if you need further assistance ok

Posted on Jul 09, 2010


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