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Author Topic: Engine seems to kick - misfire at 7k RPM??  (Read 1645 times)

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Engine seems to kick - misfire at 7k RPM??
« on: August 09, 2018, 04:50:58 AM »
Weird one, the engine is actually in a kit car and as the revs build to around 7,000 the engine power has a momentary loss in power (about 1/4 of a second) and then power comes in strongly to redline, its almost like a vtec?? Its weird, its not running rough or idling badly and the rev round once the kick happens is strong.

This momentary loss actually feels good as it boots you back into the seat once the power comes back on but I know it isn't right, its very quick, but its definitely there.

The engine has just has new NGK iridium plugs (CR9IEX), a dry sump fitted, fresh oil, serviced and a new air filter.

Could it be plug gaps? Coil pack?  :huh:

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Re: Engine seems to kick - misfire at 7k RPM??
« Reply #1 on: August 09, 2018, 03:29:10 PM »
Are you sure its the engine breaking down and not the gearbox jumping out of gear and back in which would be more common ?
If you think its electrical do the gauges flick or cycle like at key on 
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Re: Engine seems to kick - misfire at 7k RPM??
« Reply #2 on: August 10, 2018, 01:50:38 AM »
Could be actually, whats the remedy for this? gearbox rebuild?

Any idea on a rough price for this work?

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Re: Engine seems to kick - misfire at 7k RPM??
« Reply #3 on: August 10, 2018, 05:40:22 PM »
If it has just started doing this you may just need shift forks replaced , can be done (not easily )without major disassembly
Otherwise full pull down on the bottom half and get gears checked, replaced or backcut depending on condition, cost will vary, ask around
Where are you ?
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Re: Engine seems to kick - misfire at 7k RPM??
« Reply #4 on: August 13, 2018, 01:20:25 AM »
Done lots of reading on the topic now and others that have had the issue and it certainly seems that my second gear is going as have many before. I will just have to sort it, I have made some enquiries and thank you for your help.