I just had a b16a with ys1 tranny installed into my 91 crx si with an aem cold air intake, stage 3 clutchmasters clutch, and a mugen chipped pr3 ecu, vtec is suppose to engage at 3800 rpm and no rev limit, but the vtec isnt working, I checked the wiring it all seems ok, took the vtec solenoid apart and the filter screen was a little dirty, cleaned it and the plunger was stuck, so I fixed the plunger and now it moves freely on the spring, put it all back together and still no vtec, there are no ecu codes, oil is full, but I'm going to check the oil pressure this next weekend, Someone told me to check the speedo, but I don't know how??? Please help, the motor runs strong, but you can tell its lacking the power of when the vtec is suppose to engage.

Also is there a way to tell if the pr3 ecu is obd0 or obd1.

 

That doesn't sound like a real Mugen chip at all, Do you have another b series vtec ecu to test?

 

Why is the VTEC engagement point set at 3800? That is insanely low.

And how do you know that you don't have any VTEC? There really isn't that much of a difference in feel after cross-over on a mostly stock B16A IMO.

 

No, thats the only ecu I have. The place I had the motor installed gave me that ecu. I only know that the vtec is suppose to engage at 3800 rpm and has no rev limit because when I googled a mugen pr3 ecu thats what the specs said for a mugen pr3 ecu

 

I know the vtec is working because the motor feels as fast as my sohc non vtec si motor and because a couple of buddies of mine have stock b16a motors and you can hear when the vtec engages and the rpms start climbing a lot faster.

 

I'm guessing that it's an eBay "mugen" ECU then. Try using the OBD0 B16A stock ECU to see if it works.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chancock &raquo;</TD></TR><TR><TD CLASS="quote">No, thats the only ecu I have. The place I had the motor installed gave me that ecu. I only know that the vtec is suppose to engage at 3800 rpm and has no rev limit because when I googled a mugen pr3 ecu thats what the specs said for a mugen pr3 ecu</TD></TR></TABLE> That sounds like a **** poor setup for a motor like yours.

That also might be it, you can always wire up a vtec light just to test things. I've done that trouble shooting a friends car, then promply tossed it lol.

 

How do you wire up a vtec light? I was orginially suppose to get a stock pr3, but they didn't have any in stock so they ask if I would take a chipped pr3, and I asked them if it would make a difference and they told me only for vtec engagement and no rev limit, they told just don't go past 8200 rpm.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chancock &raquo;</TD></TR><TR><TD CLASS="quote">How do you wire up a vtec light? I was orginially suppose to get a stock pr3, but they didn't have any in stock so they ask if I would take a chipped pr3, and I asked them if it would make a difference and they told me only for vtec engagement and no rev limit, they told just don't go past 8200 rpm.</TD></TR></TABLE> Search on the vtec light i'm sure some one has a write up, I don't have my wiring stuff sitting in my office so I'm not going to give you a 50% complete how too, it'll just get you lost.

You got reamed sadly you shoulda taken the stock one. Ebay or use the classifieds for a stock ECU.

That chip is probbly your problem, and if it's not it'll make your car suck.

 

What do you mean it'll make my car suck?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chancock &raquo;</TD></TR><TR><TD CLASS="quote">What do you mean it'll make my car suck?</TD></TR></TABLE> Your A/F ratios are probbly just randomly done and richend up, god knows what your timing looks like and your vtec is insanely low for your car.

No rev limit is just flat foolish on any car.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by The Maxidermist &raquo;</TD></TR><TR><TD CLASS="quote"> Your A/F ratios are probbly just randomly done and richend up, god knows what your timing looks like and your vtec is insanely low for your car.

No rev limit is just flat foolish on any car.</TD></TR></TABLE> x2

 

x3 ^^

 

Thanks for the info I just ordered a stock pr3 ecu should be here by this weekend I also ordered a vtec subharness from rywire.com because the wiring that the place did was ghetto so that also might be the problem why the vtec isnt working. I also bought a service manuel off ebay on cd for a b16a thats installed in crx si. If anyone else has any ideas on why the vtec isn't working would be greatly appreciated. Thanks for all the help so far.

 

easy way to wire up a VTEC light is to ground the - wire of the solenoid and run any 12v light/led into the car off the + wire. when VTEC engages the light will come on.

 

It may actually be working. With the changeover set that low it would be undetectable with your set up. IMO

 

I thought the same thing, but you would still feel the power in the upper rpm range. Also the vtec is vtec no matter where it engages isn't it, when it engages it goes to the lobes on the camshaft that are higher right so it really shouldn't matter. I'm going to wire up a vtec light and see if that comes on this weekend also hopefully get all the stuff I ordered this weekend to troubleshoot, but I don't think the vtec has ever worked for the simple reason that when I pulled the vtec soleniod off the plunger inside was stuck and didn't move freely. I got the plunger unstuck and know it moves freely but no difference in power, so might be bad wiring, bad solenoid, pressure switch, oil pressure, vaccum, there are no ecu codes just a short flash when you first turn the key on and thats normal. Anu ideas where I should start, whats the most common reasons why the vtec don't work, someone was telling me about the speedo or something, how do I tell if thats good or not with no ecu code?

To get the ecu codes you just turn the key on right??

 

bump