"OBD1" is generally used to refer to honda engine electronics from 92-95. Accords/Preludes used OBD1 connectors as early as 1990. This is not an official standard, unlike OBD2.

OBDI ECUs (92-95)

• P05 : 92-95 OBD-1 Civic CX (D15B)
• P06 : 92-95 OBD-1 Civic DX (D15B)
• P07 : 92-95 OBD-1 Civic VX (D15Z1)
• P08 : 92-95 OBD-1 Civic/CRX VTi/VXi (sohc vtec)
• PR3 : 92-93 OBD-1 JDM Integra RSi/XSi (B16A)
• PR4 : 92-93 OBD-1 Integra RS/LS/GS (B18A)
• P27 : 92-95 OBD-1 Euro/Asian Civic (non-vtec 1.6l)
• P28 : 92-95 OBD-1 Civic Si/Ex (sohc vtec d16z6)
• P29 : 92-95 OBD-1 JDM Domani (sohc zc)
• P30 : 92-95 OBD-1 USDM Del Sol DOHC Vtec Si/EG SiR
• P51 : 92-93 OBD-1 JDM Ascot Innova 2.3l Si-Z H23A CC-4 DOHC non-vtec
• P54 : 92-95 OBD-1 JDM Domani/1.8l Accord (1.8L B18B DOHC)
• P61 : 92-93 OBD-1 Integra GSR
• P70 : 92-95 OBD-1 Domani (sohc vtec zc - no oil pressure sensor reading)
• P71 : 92-95 OBD-1 Integra (sohc vtec d16a)
• P72 : 94-95 OBD-1 Integra GSR
• P74/75 : 94-95 OBD-1 Integra RS/LS/GS
• P76: 94-95 OBD-1 JDM Integra (sohc zc)
• P84 : 92-95 OBD-1 JDM Civic ETi (VTEC-E auto)
• P91 : 92-95 OBD-1 JDM Civic Coupe (sohc vtec 1.6)

• P11 : 92-95 OBD-1 Prelude 2.0i BB3 (F20A4 non-vtec)
• P0 A : 94-95 OBD-1 Accord EX (F22B)
• P0 C : 92-95 OBD-1 Accord 2.2L (??? F22B DOHC non-vtec)
• P39 : 92-95 OBD-1 JDM Accord SOHC VTEC
• P13 : 93-95 OBD-1 Prelude Vtec (H22A)
• P14 : 93-95 OBD-1 Prelude Si (non Vtec - H23A)

• PT3 : 90-93 OBD-1 Accord SOHC F22A non-vtec OBD-1

• PK3 : 90-91 OBD-1 Prelude (B21a1 motor) OBD-1 Plugs

• PR7 : 91-94 OBD-1 NSX C-series V6