Engine Miss in 4th gear only
#1
Posted 06-11-2011 09:04 AM
-only 4th gear
-happened around 6800 rpm
-tach would drop down to 6500 and bounce. Hesitation would disappear after shifting to 5th
-car was going down the straight
-didn't happen every lap, but perhaps 75% of the laps
-car ran fine the previous day(Saturday)
-it did rain the previous day(Saturday) and the car was put in the trailer damp
-Changed plugs(new plugs, same brand, NGK) and air filter(paper STP) before racing in Sunday, after Saturday session.
Suggestions welcomed.
Thanks.
#2
Posted 06-11-2011 09:39 AM
What about at 6800 when your going thru the gears, say in 3rd.
Pat
#3
Posted 06-11-2011 09:51 AM
Chris
Happiness is a dry martini and a good woman ... or a bad woman.
- George Burns
#4
Posted 06-11-2011 10:47 AM
#5
Posted 06-11-2011 11:32 AM
More than likely the alignment on your crank trigger is off, set the gap at .045 -.055 and see what happens. They move, there will be tech bulletin out shortly allowing a bracket to hold the sensor from moving.
If that doesnt do it, you have all the other normal stuff to look at...
plugs,plug wires
cam position sensor
coil
fuel pump
fuel filter
I would attack in that order...
Jim
East Street Auto Parts
Jim@Eaststreet.com
800 700 9080
#6
Posted 06-13-2011 08:55 AM
Frank
TnT Racing
SCCA Ohio Valley Region
#7
Posted 06-13-2011 11:28 AM
Turned out to be an injector plug that would only come loose above 80mph?
Good luck.
#8
Posted 06-13-2011 01:01 PM
Dave
Dave Wheeler
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#9
Posted 06-27-2011 07:23 PM
Thanks.
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