Check Engine Reset.

[deafanddiabetic]

I had an engine code for cylinder one misfiring. I replaced the spark plugs a few months ago but after 120k the wires had never been changed. I put new coil packs, spark plug wires and spark plugs on my P5. Of course, my check engine light is still on but no auto parts store will clear it for me. Multiple ones said, "that's illegal and we can get fined for it". Weird, you guys can check the code for free but not clear it once I spend $100 at your store to fix it in the parking lot in 5 minutes?

Anyway,

In my old Honda Accord, there was a procedure for clearing the engine codes, holding in the odometer button, turning off ignition, turning on ignition, letting go of odometer button.

Is there anything like this for the P5? How do I clear an engine code without spending $30-$50 on a freakin' auto scanner?

 

[hornsfan10609]

For your honda that wasn't a CEL reset, that's the maintenance light reset procedure. You can unplug the negative terminal on the battery and turn on the headlights for a second or hit the brake pedal and then let it sit for a minute. Then reconnect the battery and the ECU will be reset. It's a good idea to do this anyway after replacing parts.

 

[pcb]

Disconnect the negative battery terminal,... Turn on your interior light (to fully drain any capacitors and such)... Wait 10 minutes then reconnect the battery.

This completely rubs out the ECU's memory. Your car will run crappy for about 100 miles as it relearns the car.

Buy your own code reader... They're only 10-20 bucks.

This one broadcasts to your smartphone... Tells you EVERYTHING about every sensor on your car. (and it will rub codes too.)

 

[deafanddiabetic]

Appreciate both replies. hornsfan, you've got me curious, why is it good to reset the electronic control unit once in awhile?

 

[MrGiggles]

The Bluetooth ELM327 adapters are awesome. You can view live data as well as view and clear codes. For less than 20 bucks it's a no brainer, I bought mine from Amazon, I believe it was a Vgate. Use the Torque Free app for Android, and there is also a Torque Pro for 5 bucks.

 

[hornsfan10609]

Appreciate both replies. hornsfan, you've got me curious, why is it good to reset the electronic control unit once in awhile?

The computer re-learns all the parameters for the sensors and adjusts to the proper reading. The computer can compensate for certain changes but over time the car begins to run worse. Resetting the ECU always seems to help the Proteges run better. It will be funky for the first few miles (NOT 100, just at first) as it is learning and adjusting but it will run better.

 

[pcb]

... It will be funky for the first few miles (NOT 100, just at first) ...

The worst part is when the car relearns to idle itself. My car gets very close to stalling and takes a good dozen tries before it settles down.

There have been a lot of guys who have written in about their car running like crap after they disconnected the battery for service.

(but it still takes a good 100 miles or so for the ECU to be "ready",... you can't just reset the ECU then go for an emissions test (if they plug into the OBDII port for the test))