cdt540

I just recently purchased a '02 with 110,000 miles. It does not appear the vtec is working. I had an '01 ten or so years ago and my recollection was there was a clear seat of your pants feeling when the vtec kicked in around 6000 rpm. This one nothing. It pulls strong and consistently but no vtec sensation. Just changed oil and filter (Castrol Syn 10/30). The vtec had a bit of a leak so I replaced both rubber gaskets and the o-ring for the oil pressure sensor. Are there any ways to test the vtec to narrow down the issue? I know there is an process to test the mechanical engagement using air pressure I believe but I hoping I don't have to go that far and that it is in the vtec/selonoid itself. When I had it off everything appeared ok, the spring loaded shaft moved easily and so on. Any help running this down is greatly appreciated.

Chris

Billman250

If the air filter looks dirty, change it, leave airbox lid off.

Do a pull in 3rd gear, and floor it at 4000rpm. Listen for distinctive chance at 6K, with the lid off it is a lot louder.

It sounds cool but the hp loss is 12+. But this is the best test.

windhund116

Billman! Just another cool Insider's tip. Thanks, again!

cdt540

I will give that a try. If in fact the VTEC is not working are there any diagnostics I can perform to determine where the fail point is? I am new to S2000s but what I have been able to determine so far that effects VTEC is:
1. Oil Pressure Sensor on VTEC
2. Water temp
3. RPM
4. the selonoid on VTEC
5. Computer or ECU
6. the hydraulic function of changing the valve timing

If I have to start digging into this any advice on how to confirm which of these items (and others?) is failing would be greatly appreciated.

Thanks for the help....

Chris

windhund116

I think that air pressure test would be definitive.

Billman250

VTEC system test takes special tools that pressure bolt holes in the cam towers. Based on how rare a Vtec failure is, Ill bet the bank your car is likely fine.

ISADE

Can you verify it is still the stock ECU unmodified? It's not tuned or anything is it?

cdt540

Cannot verify but I was told everything on the car was stock except the wheels. Other than an added aftermarket alarm the claim appears to be correct. I have not had a chance to verify definitively because most of my only driving recently has been in rush hour traffic, but following the advice to get to 4000 and "stand" on it, produced what I expected to feel/hear at 6000 rpm. It seems my problem has been when trying to engage the VTEC I have been just steadily accelerating expecting the VTEC to kick in at 6000 with no success just a nice steady pull. But when I stood on it at 4000, at 6000 it clearly kicked in. So it seems that it is not enough just to hit 6000 for the vtec to activate, you have be all in. It is like the ecu is also looking at throttle position (TPS) or something else to determine whether you are just at 6000 or are at 6000 and asking to bring it. Does that make sense or am I just formulating a theory around what I think I felt. Running errands at lunch today so I should be able to "test" some more

GSteg

There are few factors that must be met before VTEC engages. RPM is only one of them.

Slowcrash_101

Valve adjustment see if that helps.