HI EVERYONE.. Im trying to help my nephew out with his 91 Honda Accord ..
His check engine lamp stays on once you go up a hill .. When I jump the blue connector with the paper clip , the lamp goes out but will not produce any codes at all , the cel stays out until you drive up a hill again.. Can the ECU be faulty? Thank you so much for any response. scratchin'

 

Can be, next time the CEL comes on, don't shut the car off and check again.

Any recent work done to the car?

 

HI Poorman212 and thank you . He had just purchased the car and I do know the egr was changed but thats about it. When I pulled the carpet up where the ecu and tcu is , it looked like someone had placed a jack under the floor pan and made a hole right by the computers..And also the plate that covers the computers was missing all the nuts.. I put a few on but that light came on right when he drove up the hill.. When he stops by I will try the jumper with the engine running and Thank you again,. scratch..

 

I would check the 7.5 amp backup/radio fuse in the engine bay fuse box. I would also check the ECU fuse.

There is an important ground under the distributor on the thermostat that you should unbolt. Clean the eyelet and threads with a wire brush or some sand paper. Then reattach.

 

HI PAHonda and Thank you for the information.. I certainly will check the ground and the fuses.. Thank you again for your fine advice and I will write back as soon as my nephew brings the accord back.. Bye for now .scratch

 

Does the "clock" reset time when you/he turns it off?

 

HI There Poorman212 . I will be seeing my nephew tomorrow and I sure will check the clock after the motor turns off and restarts... I sure will let you know what happens.. Thank you so much for your help,.. scratch..

 

Maybe Poorman's suggesting the backup fuse is blown. In that case, it's like you clear the codes every time you shut off the key.

Drive & get the CEL to light up. Then DON'T turn off the engine. Leave it running. Jumper the SCS connector without turning off the engine. Does it flash any codes that way?

And let us know when you've checked the grounds too.

 

Yes Jim, was going for another way of checking PA's suggestion(s)....loosing ground or power to the ecu could casue the "loss" of the code(s) when the car is turned off...