nomadicS2k

Vac leaks I think will be harder than the IACV - unless you have some top tips to share!

GhostWKD

Well i've got loads of silicone vac hose left from my Noble so will maybe replace a few bits and see how I get on.

Technically spraying carb cleaner should tell me if there's a leak iirc (ie spray it over vac hoses and if the revs increase it's got a hole around there)

noodels

Could use a vacuum testing tool

BenRNBP

just wondering has it always done this or since fitting the CAI ? I'm wondering of the vac hoses and solenoid check valves got put back the right way round ?

GhostWKD

Always done it sadly since I got it in Jan. I'm pretty sure it's all good it's the second one I've fitted

Has had an engine rebuild in the past (2006 engine fitted with all 2004 engine parts) so not sure if it's related to that

noodels

Checked Ignition timing is advancing as it should with a strobe.
Gather would be different from a hot or a cold engine as vacuum may change things if its doing it correctly ?

noodels

Also may look at link here
https://www.s2ki.com/forums/s2000-un...-wire-1174805/

rickya

Mine does it too first thing when I start it up and then get stuck immediately in stop start traffic. It Kangaroos in 1st and 2nd gear with a slight shaky idle when changing gear. Soon stops after 5 minutes or so but can return in heavy traffic again. I have cleaned out IAC valve, throttle body, map sensor whack, done plugs, done Valve Clearances, Injector cleaner and fuel system cleaner, checked VAC pipes, checked Throttle position sensors and still no joy. I am now thinking it may need one of these items replacing but cant be bothered throwing more money at it chasing a hunch. These items are either : new IAC valve, new map sensor, 1st Lamda sensor, decat it???

rickya

Has there been cases of this causing the issue?
Is this more. likely than the Primary Lamda sensor?

GhostWKD

This sounds pretty much the same as my issue. Slight difference but very very similar based on description.

Checked vac hoses on mine yesterday and all look fine. Spraying carb cleaner around the vac hoses didn't induce any increase in RPMs etc.

My Berk HFC should arrive today so I'll put that on and see if that makes any difference (and take a look at the stock cat). Then I'll try a new IACV valve and give up after that

Do need to do my valve adjustment but imagine that wouldn't affect it this severely. Throttle position sensor is a interesting one though as mine does look like it's possibly been messed with. Readings on the OBD2 reader look about right mind (iirc 12% closed and 88% full throttle)