I orginally posted this in the GTV forum but not much response so I thought I'd move over here
1997 Phase 1 GTV, 2.0 TS.
Right.. I'm not sure if this has been there for ages and getting worse slowly or if I've just not paid enough attention and something I've done recently has caused it..... I've only had the car for 4 months and am only just started learning to do anything mechanical with it (I dont think you can own a GTV and not be at least a part time mechanic unless your very rich!)
Revving the engine the rev counter jerks upwards, every 500rpm or so (Depends on how fast you rev it), the needle jerks for a just noticable moment and then continues.. also does it on the way down as well.
It does not seem to be affecting the performance *that much* but I have nothing really to compare it to.
MAF has been replaced with a 'known good secondhand' one from someone on here, disconnecting the MAF makes the stutter worse if anything.
Work Done Recently :
Cleaned throttle body
Resonator Box on the air inlet replaced with a length of drainpipe.
Cam Cover Gasket Replaced
Oil Change (10W-40 put in to replace the black gunk that was in there)
Exhaust Mid section has a small hole in it.. patched with a clamp on patch but possibly not that tightly.
Air pipe has been throughly checked and has no splits
Air Filter box *is* cracked on one side where some gorilla has snapped off the top half of the bracket, trying to source a replacement.
After some testing (read driving too fast) today I've concluded you can hear it in the engine too.. 1st/ low 2nd not so much, same with 4th (it's there just not really noticable) however higher in 2nd and all the way through third when driving hard (acclerating foot to the floor) you can hear the engines not smooth it's going kinda.. vuv.vuv.vuv (read it out loud fast ) if that makes sense.
Now I could be being a car hypercondriac and everything is fine. However I learned my lesson with the thermostat and even the smallest things can make a big difference so I would like to be sure