Sensitive engine?

[Dylanamus]

I'm pretty sure this is a noob question and I'm not sure how to explain clearly...

When I build up speed then take my foot off the accelerator and coast, as the car deccelerates, at a certain point in rpm it suddenly losens up - as though something has disengaged). It happens from anything like passive slowing down in 4th after accidently going above 60 to rolling in second to the lights. It also jolts immediately after I take my foot off the accelerator sometimes (even if I slide it off as smoothly as possible).

Beyond this, a very similar sensation occurs when I reapply acceleration - like a jolt (even when being as gentle and smooth as possible). On some days city driving feels like I'm on a rocking horse. haha

Can anyone help me understand what is going on, so I can try and fix it? :D

Thanks!

[EuroDude]

Sounds like the throttle may be sticking.

A dirty throttle body around the butterfly can cause this. Remove the intake pipe and spray some Carby cleaner around the butterfly, and wipe it with a cloth.

Guide~ http://www.ozhonda.com/forum/showthread.php?t=35488&highlight=throttle+body

Otherwise it could be a gearbox / clutch problem, or possibly bad synchros

[Dylanamus]

I'll clean my TB and see how I go, but no that you mention it, my clutch slips when I do drag-speed shifts and my 1st to 2nd synchro occasionally grinds and my 3rd to 4th synchro grinds even when changing at 4krpm! I can only avoid grinding shifts to 4th, by sitting it in neutral for a second and slowly moving it down.

So what exactly is going on for it to "grip and ungrip" like this? What components could be causing it and what are they doing? :/

[JasonGilholme]

Could be your throttle position sensor?

[destrukshn]

or it could be a ****ed clutch.
lol.

[Dylanamus]

Well the clutch has only slipped a few times and it happened when I was really shifting like a nutter and I can't be certain that I didn't just bog the clutch briefly before completing the change. A few people with the same model car who drive mine said my clutch was good. Synchros are definitely rooted though. I'm looking into rebuilding my y1 transmission with s80 internals, but I'm not very well versed on the subject unfortunately.

I'll try the simple solutions first (ie TB and TPS) and go from there. If the gearbox can cause this kind of behaviour, then considering how rooted it is, I'd say there's a good chance it's that. :(