I'm curious about this - I don't have the technology to re-flash my onboard computer and was wondering if removing the cables (I know, negative first) would do the trick. I also found this guide and was curious if this was the real way to reset my computer.

How to Repair Your Vehicle (Basics): 9 Steps (with Pictures))

I have a 2003 Chevy Blazer with 155,655 miles on it and recently did a lot of work on it and I'm getting horrible gas mileage. So, I was hoping a reset would help me out.

 

I'd forget the 're-flash'. First let us know if you've noticed an SES (check eng.) light or if you have any trouble codes stored. Otherwise, just disconnect the batt. for 5 min. followed by 30 miles or so of casual city and freeway driving. Also let us know what king of gas mileage you're getting (should be 13 to 17+ combined depending on traffic and hills).

Meanwhile, have you replaced the front and rear 02 sensors since your recent overheating troubles? If not, and you don't have any cylinder misfire codes (starting with PO3XX), then you might consider changing at least the front 02 (or both) as long as you have no vacuum leaks (especially at the int. manifold) and the air filter, plugs, wires, cap, and rotor are good.

Unfortunately, serious and/or repeat overheating issues will often result in int. manifold gasket and/or head gasket failure. Failing head gaskets often trigger O2 sensor problems due to coolant making its way into the combustion chambers and thus the exhaust. This will almost always be accompanied with random eng. hesitation.

Note: keep a very close eye on the engine oil for signs of coolant contamination (this will turn the oil into a chocolate milk looking sludge). Also, of course, check for coolant loss.

 

unplugging the battery doesnt reset the computer

 

1. You don't 'unplug' a vehicle battery. You disconnect the terminals of a vehicle battery. 2. disconnecting a modern feed back vehicle battery for approximately 5 minutes does indeed reset the PCM or ECM. This is known as a 'soft' reset.

 

It will do nothing for deleting codes or reprogramming your computer back to stock. you wll onlt need to reset your radio stations

 

it will delete any active check engine lights and reset all the memory in your computer, idle speed, fuel mixtures, etc. basically makes it so your car has to relearn all the settings again. do it all the time at work anytime a sensor is being replaced so the computer can relearn it. some newer cars even run like crap or stall out a few times after putting in a new battery due to losing all saved settings it had. usually a few mile drive will relearn everything

so yank the battery for like 10+ minutes or take off both terminals and hit them together making sure they are completely off the battery

 

Head is still in good shape, no symptoms of failure. All (3) O2 sensors are fine (at least that's what my OBD-II reader says).

I did replace the fuel filter and that's helping with the hard crank issue I've had and some of the acceleration issues. I hadn't changed that filter in 50K miles (I know, I know...) so it was needed.

 

Basically, I want it to "re-learn" the driving patterns (if that's the correct terminology). I've done SO MUCH to my Blazer over the past month - I'm thinking it's internal brain still thinks it's broken.

Don't care about resetting anything - just want to get this truck situated properly.

One more thing -- I do need a new power steering pump (yay...) - after that's replaced, I hope that I'm done (for now) with repairs!!

 

yep, just pull the battery for a while, or touch the negative and positive cables together (with battery disconnected) to clear out all memory and re-drive