SWAP problem

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I've almost finninshed my long lasting swap (Prelude 92 Si to JDM H22A VTEC). But still there's a problem. VTEC is not working and the light "check engine" is on. I connected VTEC solenoid valve (grn/yel A4) and VTEC Pressure Switch (blu or lt grn D6). But I can not find where I get the ground wire for VTEC pressure switch (blk/red A26). Everybody in internet always refer to such a connection, but one local technician that helped me, said that since the Pressure Switch is on the block, it's already grounded. Then, maybe I ran the wire to a wrong switch (to Knock Sensor?)? Does anyone has a picture of it? Where the black wire should come exactly from the pressure switch? Please explain.
 
Originally posted by TWISTEDIMAGE@Aug 4 2005, 07:01 AM
ground it. the press switch does not matter witch wire goes to computer, one wire goes to computer and one goes to chassis ground
[post=535536]Quoted post[/post]​


And that one that goes to chasis ground, where does it go from? From the connector or from the switch itself? I'm mixed up, 'cause I'm not sure if I found the proper connector.
 
Originally posted by TWISTEDIMAGE@Aug 4 2005, 07:01 AM
ground it. the press switch does not matter witch wire goes to computer, one wire goes to computer and one goes to chassis ground
[post=535536]Quoted post[/post]​


I checked some pictures of VTEC solenoid and VTEC Oil Pressure Sensor on the web. It appears to be that I have a problem. Instead of the VTEC Oil Pressure Sensor there is a bolt on its place... :eek:
Strange. But I must confess that I was talking not about usual H22A VTEC engine, but about H23A VTEC, taken from JDM Accord Wagon SiR 1999. A very rear one. Since it's OBD2 (1999), then, maybe it doesnt have the sensor (operted by ECU?)? Or it was broken during transportation, which seems to me more realistic.
Does anyone have an idea?
 
Just found out that all Preludes from 1997 to 2001 have bolts there exactly like I do. Then, it's not clear what sensor/unit performs the VTEC Oil Pressure Sensor function on those ludes.
Does anyone know?
 
Originally posted by Atrevido@Aug 4 2005, 08:59 AM
Just found out that all Preludes from 1997 to 2001 have bolts there exactly like I do. Then, it's not clear what sensor/unit performs the VTEC Oil Pressure Sensor function on those ludes.
Does anyone know?
[post=535661]Quoted post[/post]​


Just check under OIL PRESSURE SENSOR. It's probably a yellow wire with a red stripe, near your oil filter. On non vtec to vtec swaps, the oil sensor wire and vtec oil sensor wires are interchangeable. :)
 

reikoshea

Moderator
VIP
yeah, and if you need to ground it, you can just ground your vtec wire to the block...there is a screw on mine that i grounded it to.
 
Trying to solve my problem with lacking VTEC oil pressure switch I found some interesting info. It says:

Wire the VTEC components. (ECU: P13, P28, P30, P61, P72)

• Connect the green wire in the supplied sub-harness to the
green/yellow wire on the 1-pin VTEC solenoid connector.

• Connect the light blue wire in the supplied sub-harness to the
blue/black wire on the 2-pin VTEC oil pressure switch
connector. The remaining black wire on the 2-pin VTEC oil
pressure switch connector needs to be grounded.

• Many JDM engines DO NOT have a VTEC oil pressure switch.
If using a USDM ECU with an engine lacking a VTEC oil
pressure switch, simply splice the light blue sub-harness wire
into the green sub-harness wire. Then connect the green
sub-harness wire to the VTEC solenoid as stated above.

Source: http://www.boomslang.us/obd0_1.pdf


Pls comment.
 
And one more

I wired in a wire for the oil pressure switch from the ECU pin, and grounded it out to the body of the VTEC soelenoid (I read that this is the best way to do it when putting a JDM engine into a USDM car, and it is much cheaper than buying a soelenoid). I don't want to have to buy a soelenoid, so I will try that as a last resort, and hopefully, I can talk my brother in law into letting me try his out first.

http://www.honda-tech.com/zerothread?id=1310531


What you guys think about this?
 
Here is the end of the above posted problem. So, I guess I should try this to solve my problem.

SUCCESS!! I feel like such an idiot. Like I said before, I don't have a Oil pressure switch, so what I did originally was take the solenoid wire to A4, and I thought I needed to make a circuit so I took the oil pressure switch wire from D6 and grounded it. This made VTEC work, so I thought that was wired right.
But the problem was that you are supposed to take the wire from D6 and splice/tap the wire into the solenoid wire coming from A4. Thats all you have to do to wire a JDM engine for VTEC when using an ECU that is looking for that oil pressure switch.

What confused me is when I read the how to, it referred to grounding a wire from a clip that I didn't have, so that is why I thought you were supposed to ground the OPS wire. The write up was assuming that you were using a OBD2 integra wiring harness for simplicity, but I was using my stock DX harness and just changing the plugs out.

Well I feel stupid, but at least I have my swap running right now and I didn't have to buy anything really expensive to fix it. I hope this whole mess helps someone else out. If it does it will almost have been worth it.

http://www.honda-tech.com/zerothread?id=1310531&page=2


Still waiting for your comments, guys.
 
I've never heard someone say that they didn't have an oil pressure sender. It's not just for VTEC, so I don't know why they would abandon it. I personally, would just add a sensor to the back of the block, and use the one wire that it requires to make things right.
 
Originally posted by tab@Aug 8 2005, 09:22 PM
I've never heard someone say that they didn't have an oil pressure sender.  It's not just for VTEC, so I don't know why they would abandon it.  I personally, would just add a sensor to the back of the block, and use the one wire that it requires to make things right.
[post=537420]Quoted post[/post]​


:) Bingo! I've connected the wire that goes from ECU pin D6 to the wire A4, and now it's working! VTEC works great, without the VTEC OIL PRESSURE SWITCH. But that is really strange. Why does Honda use the switch at all, if it's not a must? I don't think that "Boomslang" would recommend something wrong. I know that on the 5th gen. Preludes there was no VTEC oil pressure switch. I thought, if so, it should be ruled by its ECU - P5P. But now I'm not sure if it's about ECU at all. I think there was a jumper in P5P, connecting equivalents for A4 and D6.
But still, the question is not solved: Why does the switch exist at all?
 
Originally posted by tab@Aug 8 2005, 09:22 PM
I've never heard someone say that they didn't have an oil pressure sender. It's not just for VTEC, so I don't know why they would abandon it. I personally, would just add a sensor to the back of the block, and use the one wire that it requires to make things right.
[post=537420]Quoted post[/post]​


I think you misunderstood me. I was talking not about oil pressure sensor/sender, but VTEC oil pressure switch. Which should be located right beneath the VTEC Solenoid Valve.
 

reikoshea

Moderator
VIP
I think it is so you cant use VTEC until your engine is warmed up. I know on more than one occassion ive been bad and forgotten to get it warmed up before i hit it hard.

Maybe im wrong but hey...at least im posting again.
 
Originally posted by reikoshea@Aug 9 2005, 04:08 PM
I think it is so you cant use VTEC until your engine is warmed up. I know on more than one occassion ive been bad and forgotten to get it warmed up before i hit it hard.

Maybe im wrong but hey...at least im posting again.
[post=537750]Quoted post[/post]​


I'll try to run VTEC without warming up.
 
Originally posted by Atrevido+Aug 9 2005, 04:24 AM-->
@Aug 8 2005, 09:22 PM
I've never heard someone say that they didn't have an oil pressure sender.  It's not just for VTEC, so I don't know why they would abandon it.  I personally, would just add a sensor to the back of the block, and use the one wire that it requires to make things right.
[post=537420]Quoted post[/post]​


I think you misunderstood me. I was talking not about oil pressure sensor/sender, but VTEC oil pressure switch. Which should be located right beneath the VTEC Solenoid Valve.
[post=537731]Quoted post[/post]​


Yeah, that's what I get for speed reading through all these posts.

I'm with Reiko. I know that VTEC does not work until the car is warmed up. It still doesn't make sense to me though, since my engine is also JDM and has all the necessary components. I didn't have to jump those wires.
 
Originally posted by tab@Aug 10 2005, 05:47 AM

Yeah, that's what I get for speed reading through all these posts.

I'm with Reiko. I know that VTEC does not work until the car is warmed up. It still doesn't make sense to me though, since my engine is also JDM and has all the necessary components. I didn't have to jump those wires.
[post=538136]Quoted post[/post]​


What year is your JDM engine? If 1993-1996 OBD1, then, most probably you should have the VTEC Oil Pressure Switch. If 1996-2001 OBD2, you might not have it (mine is 1999-2000).
As for VTEC on unwarmed up car, it works, I checked. That is really starange. Then, what is the difference between having and not having the VTEC Oil Pressure Switch? :(
Does someone know?
 

reikoshea

Moderator
VIP
......i dont know what to say to that...I would think that the OBD2 would NEED an oil pressure sensor...its got everything else. If you hit VTEC when you start your car you found your answer though. Thats what that switch is for.
 
By the way, guys, does it make any difference which fuel pump to use?
I mean, I left my old non-VTEC fuel pump to work with the new VTEC engine.
Do they have noticeable difference or it doesn't matter. Will my car run better with the proper fuel pump?
 
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