hey all i need a little help. i have a 93 accord 2 door with an h22a4. the motor is a 98 vtec but i have no power from the vtec. i have a p27? computer so it should be getting power. does anyone know how to test the vtec to see if the solenoid needs to be replaced??? thanx for ur help

 

I think that we need some more information before you start troubleshooting.

Which wiring harness was used for the swap (the original 93 harness or the 98 prelude harness).

I also don't know which car the P27 ECU was originally made for.

You need to verify the wiring first before throwing in a new vtec.

 

the swap was done when i bought the car but i was told the harness and all came out of a 98 prelude

 

ok i did a search and found out the p27 computer was from (P27 : 92-95 OBD-1 EG JDM Civic 1600 sohc) so now im wondering if i need a diffrent comp

 

There is a lot going on with your car that still needs to be sorted out.

The 98 prelude wiring harness plugs into an OBD2 ECU. The 92-95 Civic ECU has the OBD1 connection. Is there some kind of conversion harness that was used to adapt the OBD2 prelude connector to OBD1?

Once all of this is sorted out, you will have to figure out how your P27 ECU controls the vtec. Then you will have to determine how the vtec on your engine need to be controlled.

 

ok im sorry this is my first swapped engine honda!!! the comp is actually a 37820-p72-a01 i finally found where the code is. so any info on this ecu u could point me to (like a pin diagram) would be very very helpful!!1 ty for all ur help

 

I had a link somewhere's on my computer, I will see if I can find it for you..

 

ty very much btw my comp is in fact an obd1 comp

 

Just from doing a google search the ECU is for a 94-95 Acura Integra GS-R. I verified the part number on an OEM acura parts page.

You can get a 94 Integra Shop manual from the spooner link in the online manuals thread in the DIY section. You should also download the 98 prelude shop manual from that site.

On the P72 ECU: Pin A4 (grn/yel wire) is the Vtec Solenoid Valve. Pin D6 (blu/blk) is the pressure switch.

It looks like the solenoid is operated the same way between the Prelude and the Integra. I am not sure about the pressure switch. I'll keep digging around.

Are you getting an error code that is leading you to suspect a vtec problem? If so, what is that code?

 

I used to have a 95 GSR. Here's what I had saved as an ECU pin-out

A01 INJ1 (brn) injector 1 (close ground to fire)
A02 INJ4 (yel) injector 4 (close ground to fire)
A03 INJ2 (red) injector 2 (close ground to fire)
A04 VT SOL (grn/yel) VTEC solenoid valve (B18C1 only)
(VTEC solenoid valve is self-grounded)
A05 INJ3 (blu) injector 3 (close ground to fire)
A06 O2SHTC (orn/blk) O2 sensor heater (close ground to turn on)
A07 FLR1 (grn/blu) fuelpump relay (close ground to run)

A09 IACV (blk/blu) idle control valve (close ground)

A12 FANC (grn) radiator & condenser fan relays
A13 MIL (grn/orn) MIL lamp (close ground to light)

A15 ACC (blk/red) A/C clutch relay
A16 ALT C (wht/grn) alternator (control?)
A17 IAB CS (pnk/blu) IAB control solenoid valve (B18C1 only)
(yel/blk) IAB powered from term.2 of main relay

A19 FAS (yel) to TCM (auto trans only)
A20 PCS (red) EVAP purge control solenoid valve
A21 ICM 1 (yel/grn) to ICM

A23 PG1 (blk) power supply ground G101
A24 PG2 (blk) power supply ground G101
A25 IGP1 (yel/blk) 12v power from main relay (2)
A26 LG1 (brn/blk) ground G101


B01 IGP2 (yel/blk) 12v power from main relay (2)
B02 LG2 (brn/blk) ground G101
B03 AFSA (grn/blu) to TCM (auto trans only)
B04 AFSB (gry) to TCM (auto trans only)
B05 ACS (blu/red) A/C switch

B07 ATP PN (lt grn/blk) auto trans (grounded in P or N)
B08 PSP SW (grn) PSP switch (power steering pressure??)
B09 STS (blu/wht) start signal
B10 VSS (orn) signal from VSS
B11 CYP P (orn) (shielded)
B12 CYP M (wht)
B13 TDC P (orn/blu) (shielded)
B14 TDC M (wht/blu)
B15 CKP P (blu/grn) (shielded)
B16 CKP M (blu/yel)


D01 VBU (wht/blu) battery via backup fuse
D02 BKSW (grn/wht) brake switch
D03 KS (red/blu) knock sensor (B18C1 only)
D04 SCS (brn/wht) service check connector

D06 VTP SW (blu/blk) VTEC pressure switch (B18C1 only)
(VTEC pressure switch ground G101 @ T-stat)
D07 TXD/RXD (lt blu) data link connector
D08 BARO OUT (lt grn) to TCM (auto trans only)
D09 ALT F (wht/red) alternator (charging rate signal)
D10 ELD (grn/red) electrical load detector (USA only)
D11 TPS (red/blk) throttle position signal

D13 ECT (red/wht) ECT sensor
D14 O2S (wht/red) signal from O2 sensor
D15 IAT (red/yel) IAT sensor
D16 VREF (wht/blk) to TCM (auto trans only)
D17 MAP PB (wht/yel) MAP sensor signal?

D19 VCC1 (yel/wht) power to MAP sensor?
D20 VCC2 (yel/blu) power to TP sensor?
D21 SG1 (grn/wht) signal ground?
D22 SG2 (grn/blu) signal ground (O2s?)