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danielbeeson
07-11-2002, 11:35 AM
My check engine light is on... What can I do to trouble shoot the problem, besides all of the obvious like fliuids etc.

Thanks for your help,
Dan Beeson
www.beesondesigns.com (http://www.beesondesigns.com)

davew
07-11-2002, 11:51 AM
Its a race car, the CEL is supposed to be on...whats the problem?? http://Forums.ImprovedTouring.com/it/wink.gif j/k

You can get the blink code from the ecu and then look it up in a helms to see which sensor is throwing it and troubleshoot from there. Thats the usual approach....

If you don't know how to do this you can find the proceedure in the helms.

dave w

greg_umbay
07-11-2002, 12:49 PM
The same thing happened to me after spinning in a race. The best thing is to get the code reader. I can try and describe a technique that can be used once or twice. When I had my check engine light come on, Honda guru and my driving instrucor Nick came by and chewed me out for not having the right manual, code checker and for spinning in the first place. Nick warned me that this technique can do some damage to the ECU. Basically he took a small wire and stripped both ends and placed it the leads where the code reader plugs in. We then turned on the car to ignition (did not crank the motor). Then we counted the number flashes the check engine light displayed. The lights flash in rythym, 1 pause 1,2,3 repeat. Or it could flash 1,2 pause 1,2,3 The cheap and nasty Chiltons manual I _had_ was adequate enough to describe the code sequence decoding and the error codes.
I was chewed out by Nick again and was told not to use this technique and to go out and get a code reader.

Nick's a great guy and 4 time ITA champ. His Honda knowledge is credible, he runs his own Honda - Acura service shop.

[This message has been edited by greg_umbay (edited July 11, 2002).]

downingracing
07-11-2002, 03:46 PM
Dan, I use a big piece of tape over the light! (Mine's been on since the day the exhaust came off the car - 5 years)

Hope to see you at the track soon!

Matt

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Matt Downing
www.downingracing.com (http://www.downingracing.com)

Tyson
07-11-2002, 04:01 PM
Greg, i dont understand why nick had to jump the leads to the ecu. dont all honda ECU's have the LED?

whenever the CEL is on, you look over to the ECU and it will flash the appropriate trouble sign. then you can let us know, or look it up yourself what it points to. doesnt necessarily say whats wrong, just what system is having problems.

davew
07-11-2002, 04:24 PM
depends on the year. pre-obd have lights on the ecu that blink. obd-1+ have a data connector under the dash that has to be jumped to get the MIL lamp to flash the code. using a jumper wire is very very unlikely to damage the ecu in any way as that is what the honda part does and what the helms dictates...

-dw

Tyson
07-11-2002, 04:48 PM
Hm.. didnt know they changed. Thanks.

Gord Galloway
07-11-2002, 11:41 PM
Just to let you know...pre 91 ish Acura and Honda's used a LED in the computer, all you have to do is peel back the carpet on the passenger side firewall, turn the key on and count the flashes, 1 flash=code 1, 10 flashes=code 10,etc. Post 92 you had to jumper the connector located by the heater blower motor. BY THE WAY..the code reader you buy is nothing more than a fancy jumper wire. There is nothing wrong with using a jumper wire and I use this method every day at work. Jump the connector (2 pin and not connected to anything, usually a blue plug) Once it is jumpered turn on the ignition and count the # of times the check engine light flashes.
once you know what code is tripped then you can diagnose that area and find the problem. As far as all you other guys go why is your check engine lights coming on after changing exhast???? If you have an OBII vehicle then it is a result of having no rear O2 sensor feedback or heater operation. I have heard of guys plugging in a o2 sensor and zip tying it to the undercarriage just so that it is "sniffing" fresh air. There really isn't any reason the light should come on and if it does the computer ususally goes back to closed loop meaning that it isn't running to peak potential. If there is more too this would someone mind filling me in on the missing details.

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Gordon Galloway
Honda CRXsi
IT2 #32

davew
07-12-2002, 12:29 AM
peel back the carpet?? This is IT...ain't no carpet in my crx son.... http://Forums.ImprovedTouring.com/it/wink.gif

if you remove the exh system including the cat and run a straight pipe off the header w/ an o2, you will generally trip the MIL...its ok. its not in default (limp) mode...just open loop...which can equal peek potential if you have your maps dialed in right...

-dw

danielbeeson
07-12-2002, 10:33 AM
Thanks everyone for all of the input...
The car still being built, and yes, the carpet is still in the car!
The car: 1995 honda civic ex

I will look for the code and post it.

Thanks again,
Dan Beeson