I just bought a '95 Accord, and it has an OBD1 code 20. I have found lots of stuff on how to figure out what the problem is for other cars, but nothing that applies to this. It also has a code 41 (O2 sensor), but I don't think the two have anything to do with each other. Thanks!

 

Code 20 is for the ELD (electrical load detector). It's a sensor built into the fusebox in the engine compartment. (It measure the overall electrical load so the ECU can do a better job holding a steady idle speed.)

Code 41 is for the preheater in the oxygen sensor. Unplug the sensor & measure electrical resistance between the 2 same-color (black?) wires. Should be 10 to 40 ohms. Normally a bad heater will be open-circuit.

If the sensor-heater is OK then post back for searching for wiring problems in the car.

 

Thanks for the advice Jim. I went to check the O2 sensor and the wires were cut, so that was a no brainer. I have since replaced it. I also tested the ELD, and it is bad, so I need to find a new fusebox. Now I have a new code - 4. It's the Crankshaft position sensor. I already tested the sensor though, and it tests fine. The car is running pretty bad though, missing at all speeds (though it is really bad on acceleration). Any ideas on what could cause this? Also, I got the car used from a friend, and he doesn't know if the timing belt has been changed. Is there a way to figure that out without just replacing it? Thanks.

 

Check crankshaft position sensor ohms at the ECU. You'll need to remove the ECU cover, module and disconnect from harnesses. A shop manual is necessary to find the correct harness pins to probe for resistance. Check Online Manuals for download links to a 94-97 Accord Manual.

I recently had to replace my 94 EX ECU due to persistent CYP sensor (cylinder (TDC) sensor in distributor). Your sensor is very similar and may be in distributor or on engine near timing belt. After checking resistance at the ECU (still good), I decided to replace the ECU. This fixed the problem. See my posts for more details.

good luck

 

So I bought a fuse box from a guy parting out a 95 Accord, and need to find out more about the crankshaft position sensor. I ohmed it out and the sensor itself tested fine. I reset the CEL, and it came back almost instantly. I know it plugs in at the distributor, but don't know where the sensor itself is. I have read somewhere that a magnet may have gone bad on it, and I know it may be near the timing belt. Would it be under the cover? The part is expensive new (for a sensor)...I'm trying to decide if I should do this myself or take it to a shop.

 

It is one of the three magnetic sensors in the distributor. If that sensor is bad, then you will have to replace the distributor. You measured the resistance at the distributor plug, but you didn't mention if you measured it at the ECU plug?

 

So I have now replaced the Crankshaft position sensor twice, and continue to get the same code I did before, and the car is running terribly. In answer to PAhonda, I did not check the resistance on the ECU side - I'm working with a Hanes manual, and it says if the resistance checks out on the sensor side to take it to the dealer. I obviously don't want to do that. Does anyone know what the resistance value on the ECU side is supposed to be? Am I going to damage the ECU if I check it? I also found out it is likely the timing belt has never been changed...is it possible it has slipped? Thanks!

 

You won't hurt anything unplugging the ECU connector.

You want to test those two wires leading to the ECU. The resistance should be the same as when you measured at the distributor.

You should find the Online manuals thread and click on one of the links in the first post to get a 94 shop manual to show what pins you need to check resistance.

I doubt that the timing belt skipped teeth, because the cam and tdc sensor would detect something wrong too.

Also, to replace the crank position sensor, you need a new distributor. Did you put in a new or used distributor?

 

If sensor resistance checks same at the ECU plugs, the ECU is causing the fault.

Check ebay and car-part.com for a used replacement ECU to match exactly. I was able to get one for $30.

good luck

 

The ECU is the problem...now to find one. Thanks for the help!