slight hesitation at 5000rpm

[glyn]

My 300Zx seems to have a slight hesitation at around 4500-5000rpm, it idles fine and runs well but when i give it little tickle it hesitates goes hesitates goes etc, almost like a misfire.
I'm going to change the plugs today to see if that solves it.
Any ideas what else it may be?

 

[Mr HollowPoint]

could be a boost leak at full pressure (i.e. it doesn't begin leaking until the tubbies are in full swing and the pressure in the engine is high), MAF cutting out, plugs, wiring fault, O2 sensor failure, fuel cut due to not enough air getting in through the airfilters/MAF/Throttlebodies, etc. Could be down to tonnes of stuff. Best bet is run an ECU diagnostic after going for a run where it happens.

 

[glyn]

Yes i thought it could be one of a million things
Having said that i changed the plugs this afternoon(£50 a set, ouch) and after changing them no. 6 is missing like a ******, i swapped the plug and coil to no.4 and it's still misfiring so i'm guessing i have a wiring fault with no. 6 pot. I'm going to tackle that tomorrow.

 

[glyn]

Problem solved

Job done, it turned out it was the injector connection on no. 6. I took it off and it was green and totally minging so cleaned it all out and a good dose of the magic WD40 and hey presto good as new.