So the car is a 91 CRX Si. Obd0. Issue I'm having is that the cel will come on when I'm driving. And the ecu just blinks continuously. It seems like it's always comes on when I have like half throttle accelerating in third gear or higher. The cel will go off if I shut the car off and back on again. Comes on again at similar throttles and rpms are climbing. Doesn't come on at the same time every time only at similar throttle loads. I can punch it 1-3rd and it won't come on, but say you steadily merging on the on ramp in 3,4, or 5, it's on!! Car runs good with the cel comes on. This is starting to be a real pain in the behind. Has anybody experienced this before?? Any info,comments or questions are much appreciated!! Come on H-heads!! Thanks

 

Simple...read the codes and post them.

 

check the faq on how to pull codes, stating the light is on tells us nothing.

 

The cel only comes on while driving. If I shut the car off, it goes off. So I can't pull any code cause the cel isn't on at ignition. I'll reset the ecu and there is no blinks. But after the cel comes on, it just blinks continuously. I read up on that blinking and it states that it is oxygen content. Would it be the o2 sensor?? It's pretty old now. I know about pulling obd0 codes but never encountered something similar to this issue.

 

1 short blink is for 02 sensor. When you turn key to on, does the CEL come on for a few seconds then shut off ?

 

Well then don't turn the car off.

And, in case you need to know, the blinking for codes that you want to look at is found on the ECU itself.
There is an LED inside the ECU that blinks through a small plastic window in the ECU cover. Unlike OBD1+ which blink the codes out on the CEL light in the gauge cluster.

 

If it's a quick blink with a pause in between each blink it's your O2 sensor, if the pause between blinks is as quick as the blinks themselves and continues forever well then I have no idea what to tell you.

Also, expanding further on what "4drEF" stated, if you shut the car off the code itself is still stored in the ECU even if you no longer see the CEL lit on your gauge cluster.

 

Yes it comes on for few seconds and goes off like it normally would. And it is a short blink( on the ECU ). But a short blink over and over. Until I reset the ECU. Which I don't do because it just comes back and makes me cry.

 

[QUOTE=24TEN;49474582]If it's a quick blink with a pause in between each blink it's your O2 sensor, if the pause between blinks is as quick as the blinks themselves and continues forever well then I have no idea what to tell you.


Ya that's what it is. Quick blink with pause in between. It's not like crazy fast blinks one after the other. I'm going to take a chance and change that o2 sensor. Thanks to all for your input.

 

I had the same exact problem when I got my 89 CRX DX. Turns out the 02 sensor wasnt even connected !