Vtec problem

[kapelkert]

Hi to all , my car is a 2000 civic ek9 typer with 1996 integra type r engine. My problem is when the car comes on vtec it falls back off all the time can any one give any suggestions as to why this would happen, i am using an obd2b to 2a conversion harness

 

[RagingAngel]

do you have a check engine light and have you checked your oil level?

 

[oscarsayco]

i was having the same problem on my friends fully built type r motor till we got it tuned that fix the problem.
is you motor stock?
what ecu are you using?
try using another ecu a OBD1 be better that any OBD2

 

[Luig]

I have experienced some problem when using an OBD2b -> OBD2a and OBD2b -> OBD1 harness conversion

They have a bad conception for the timing signal. If you look in the harness you will see that :

pin A20 OBD2a ( ICM ) receives voltage from both pin B13 OBD2b ( ICM ) and pin A19 ( engine speed pulse )

It sends a bad signal to the ignition module wich can blow the coil !

In fact OBD2b ( 98-01 cars ) receive rpm signal from the ECU
Cars with OBD2a ( 96-98 ) receive rpm signal directly from the IGNITER.

I resolve the problem by cutting the Tach wire ( obd2b pin A19 ) and leaving obd2b pin b13 ( ICM ) with... obd2a pin A20 ( ICM ) lol

 

[kapelkert]

no check engine light my oil level is good and i am using standard p73 ecu

 

[kapelkert]

will have to get my electrician ck that for me luig thanks for the info