If your VTEC is completely gone, it could be something mechanical such as 1. oil pressure switch 2. VTEC solenoid. The oil pressure switch in my R was malfunctining, and I was having the same problem...car would not switch cam profiles (no VTEC). After replacing the ECU, and playing with a few other things, they finally replaced the oil pressure switch...voila! VTEC Back. Good luck.

 

Unless they went and did something else to the car when they changed the oil, I don't think that an oil change(if done right, ie filled to the correct level) will cause VTEC to stop working.

-Shing

 

Our local dealer uses Castrol GTX Magnatec, so that's what I've been using to top up mine. It's still on factory oil though (with a litre or so of GTX!) No VTEC probs this evening!

The Civic VTi seemed to lose/soften VTEC one day. So I slightly overfilled it (that disappearing/reappearing oil trick Hondas have) It seemed to fix the VTEC though!

I had to put a gallon of crap unleaded in S2K the other day (No 97 RON in many garages). That makes it run rough & throttle response is lousy.

I didn't disconnect the battery to hardwire the alarm - I just poked the connector on the terminal, after bolting on the earth. I did pull the backup fuse (among others!) to stop that irritating Peep peep peep thing when the key's in & the door's open

 

I have never seen one that made sense to me. I discounted these reports at first but enough people have reported it that they must be perceiving something. If someone has a reasonable explanation I would like to hear it.

The fuel, atmosphere, different driving conditions, or ECU reset I can understand, but an oil change should not make a perceptible difference if the car is fully warmed with a comparable weight oil.. doesn

 

Byron, the near-stalling you experienced is the ECU trying to reprogram itself. Give it some time, it will be ok.

As for the radio, there is no permanent locking... You will need to disconnect the battery again and let it sit with the terminals off for a few minutes, then reconnect and try again. Been there, done this, trying to put the S2000's code into my Accord's radio. Finally, after I locked it up 3 times, I had the radio pulled to get the serial number off and had Honda look up the code for that car.

I was told today at my dealer that the MAP sensor controls airflow into the engine (whether they know what they are talking about or not is doubtful...), so it's questionable to me whether your oil would have anything to do with it. If my dealer was talking out of his derriere, could someone please PM me with the explanation of what it really does?? I don't usually check technical threads like this one and I don't want to miss the answer!

 

Sondra S2K

I love it when women know about cars. It is really cool that you know so much about the S2000.

 

Joining the thread late, but I had the exact same thing happen to me. I changed my oil at about 3700 miles. The VTEC response was noticeably different. I was wondering what was in the original oil (besides the break-in additives) that could improve performance like that. Or, what was in the new oil that would degrade performance. On my next change I am putting in Mobil1 and will reset the ECU. We'll see what happens. Thanks for the info. everyone.

Just FYI, the VTEC isn't gone or not working at all, it simply seems less powerful. Strange.

 

[QUOTE]Originally posted by stelow
[B]Joining the thread late, but I had the exact same thing happen to me.

 

yup, the "sensor MAP" is the right term, according to what's on the device. I was looking into what a MAP sensor does, and it basically feeds back air pressure readings to the ECU. The ECU uses these readings to determine what PGM-Fi to use.

To solve your VTEC problem, I would think resetting the ECU is the way to go. The MAP sensor probably wouldn't be the problem here. Did you try pulling the fues on the ECU. I remember Ultimate Lurker saying that when he did it, the ECU had to relearn things, so the car acted strange for a few days.

 

all this is making me think that maybe the ECU is disconnected during service for testing. that might reset it causing VTEC loss until it can "relearn"...
we need a honda mechanic to tell us what they do in service-
my VTEC is definitely stronger today and it was stronger yesterday- it is coming back by itself (is stronger over the entire range, with improving kick at 6k). this makes me suspect that the ECU is relearning and adjusting.
that's my guess!
any honda mechanics out there?