I am getting this random CEL while driving the car, but it is no resident upon the next restart.

This leads me to believe it is the MAP sensor, as they typically don't remain as a background code.

Is it possible to pull the code from an ODBI car while it is running? If not, how does one get the correct information?

 

Just jump the connector, if there is a code present or in memory the ECU will display it...the ECU doesn't care if the car is running or not.

 

what does it mean when your cel comes on only when car is running?

 

the ecu is detecting something malfunctioning while the car is running. My guess will be your fuel supply, i think its code 13. aka you need a new o2 sensor, my car is throwing it, I just turn my car off and on and its gone. viola.

 

Yes, simply jump the connector and the CEL will flash.

 

the code may be gone but the problem is still there.
OP we cant help you if we dont have the code to give you suggestions on things to check

 

Only time this has ever happened to me was when I started throwing a CKP sensor code after getting off the dyno. Couldn't pull the code when the car was off, had to do it while the car was running.

In short, yes, you can get codes while the car is running.

 

Well the ecu won't let me pull the code when the car is running for some reason.

I'll give more info-

93 Acura Integra LS B18A1 auto tranny obd1. When the car is started up it runs fine. Then it misses once and runs fine again. Then misses once again and thats about when the cel light comes on.

I tried to leave it running and jump the connector, nothing. So I turn it of and turn the ignition back on jumped the connector again, nothing. Only when the car is running again do I get the cel.

The car is a friends. I told him he might just need to do a tune-up on it and it could go away. But I really wanted to find out how to do this before making him spend extra money.

I don't think the OP is here since he hasn't posted since 2006. I just used the search and didn't want to start a new thread, or I would have posted in the integra forum. Thanks for you're help everyone.

 

Finally got the cel to blink.

9 CYP - cylinder sensor

????

 

bump for help

 

still need help

 

Replace the sensor. I think CYP sensor is in the dizzy, you will need to replace the whole thing, unless you can figure out how to repair it on your own.