No matter which ECU I'm using, if vtec is set at 6k, it kicks in every time like its supposed to. However once I start lowering the engagement point, it starts to become inconsistent. If I have it set at 3800 rpms, I'm expecting to to kick in right before 4k (as it takes a split second to engage). However sometimes it won't cut in till 4300, 4500, 5000 and sometimes even 5500 rpms. So from 3800-whenever it decides to switch over, I'm running more timing and more fueling than I should be because the engine hasn't switched to the higher cam profiles yet.

I've had this issue on two different ECUs. First was on an AEM 1052 and now on KPro. I had my aem unit sent in and they told me that the vtec stuff was working fine. I believe them now since this problem is occurring on both platforms. So I've come to the conclusion that my problem is with my car.

I've pulled the vtec solenoid gasket off and it wasn't dirty at all, and I have checked my oil level whenever I've had this issue and it has always been fine.

My guesses are either a failing vtec solenoid, some electrical wiring issue/short, or maybe the type of oil I'm using. I have recently swapped over to Castrol Edge Titanium 10w30 from Mobil1 10w30 and I don't think I ever had these issues on the old oil, but this seems unlikely since it's the same weight.

 

oil pressure??

Maybe there is not enough of it to push the pins in even thought the valve opens. Do you have a gauge? If the cars delays the engagement the hotter it gets but it consistently works when relatively cold, that sort of proves it as oil pressure drop as heat rises.

 

WTF when did you go K-Pro?!? LOL, nice man. Sorry, I have nothing to contribute to your question, just a for going the K-Pro route.

 

Haha I installed KPro about a week ago. I live in Tx, so when the supercharger goes in, I wanna be able to pass inspection without uninstalling it every year.

 

This sounds about right, it engages early the first couple times I hit it, and then it get worse every subsequent time.
How would I solve this problem though? What causes low oil pressure?

Whenever the car stutters at idle, like if I rev it and the revs drop to around 500rpms and the car shakes (doesn't typically happen, but occasionally it does) the red oil light will flicker on until the rpms rise back up. I originally freaked out when this happened, but after checking oil levels I just thought it was the sensor being faulty.

 

Sounds like a journal/bearing issue. I wouldn't drive the car until you get a oil pressure gauge hooked up. (you'll need it anyways when you're SC)

If you see that Oil light come on, it's serious as that doesn't trip unless you're ridiciously low.

 

if you still have the aem you can log the vtec pressure switch input. you should see it change shortly after vtec is commanded to turn on.

You should be able to do the same in kpro, but I have never used a kpro on an s2k so i'm not sure if the s2k version supports the vtec pressure switch.

My guess would be you have an oil pressure issue.

has the head ever been apart? If the cam cap bolts are loose or a dowel is missing you'll get these issues.

 

Head as never been off before, but the valve cover has been off twice in the last couple weeks, one was to change the retainers and the other time was to install the KPro. The cam caps came off both times but the bolts were replaced with brand new bolts the first time.

Ill look into seeing if KPro can log the oil pressure switch. This happened while I was still on AEM, before the valve cover was ever removed so Im thinking it may be something internal.

I'll probably order an oil pressure sensor this week as its something I've been meaning to pick up eventually anyways.

So how's the best way to check your bearings? Would they make a noise if they were the culprit? I'm starting to think an engine swap is in my future