Is it necessary to jump the service connector just to check the timing? I know you need to warm the car up.

 

Yes it is.
My man GeeSeR has all the answers: http://integra.vtec.net/geeser/service_connector.html

 

I didn't use it to check the timing on my 98 GSR, but I did have the jumper in when I advanced the timing. I've checked the timing with and without the service connector in, there was no difference. If you do change the timing, make sure the 'check engine' light is on after you jump the connection. If it's not, the connection isn't jumped and the ECU will compensate for any changes you make.

 

Need help here..

i have 90 civic si with b18b, trying to do my timing but when i jump the service connector there no check engine light on. help please

 

AFIK the ECU only flashes the CEL if you actually have an error code. Otherwise, doesn't it stay off when the service connector is jumped?

 

no i have no error code...just want to do the timing it. it stay on or off when it jumped?

 

IIRC, Solid ON while jumped

 

Now you say it that sounds right to me. Never paid much attention to it I have to admit...

 

should always be solid on when jumped.

 

Yes its necessary to jump it to PROPERLY set timing and the CEL should be on when jumped, if not you didn't do something right!

Car should be warm and idle speed should be steady and set to the manual.