Ok, all O2's are now replaced, but

does the computer have to recalibrate itself?

Had to change out the driver's side front one, as it tripped it's code last night, which is what my mechanic said would most likely happen after he replaced the front passanger one.

Question now, is after getting it back the other day, with new spark plugs and the one new sensor, it idled REALLY smooth; after it tripped it's code last night, the idle grew a little rough. But I figured it would smooth back out after replacing all of the sensors, it's still a slight tad rough.

Will this go away after a couple hundred miles of the computer resetting itself?

I ended up buying the sensors local, so ended up with the Bosch brand. Does anyone see a problem with Bosch O2 sensors??

Typically a reset is done by disconnecting the Battery for 15-30 minutes.

then over the never couple hundred miles the ECU will relearn how to make your truck run the best.

Failed too mention that yes, I did disconnect both pos/neg on the battery prior to switching them out - left the battery disconnected for a good 30min or so, as I had to clean the pos terminal anyway.

Ok, thanks!

Bosch O2 sensors are excellent. Never heard of any issues with them.

Joel

Cool!

Just trying to figure out what IS good with Bosch and what's not. Note to self: Bosch "hot" alternators:grinyes: Bosch spark plugs :nono: :banghead: Bosch O2 Sensors :dunno: But looking good so far. Bosch oil filters :crying:

Thanks for the info!

After replacing my O2 sensor, there was just a hint of a very faint hesitation when the engine was cold. After a few hundred miles on the new sensor, that went away. Now its perfect. So yes I do think it takes some driving time for the computer to get all of its ducks in a row.

After replacing my O2 sensor, there was just a hint of a very faint hesitation when the engine was cold. After a few hundred miles on the new sensor, that went away. Now its perfect. So yes I do think it takes some driving time for the computer to get all of its ducks in a row.
yes, the computer will "re-learn" everything over a short time of driving, but it does it faster if you disconnect the battery

Disconnecting the battery on my 2002 throws the system in open loop for ~50mi of driving. Everytime you disconnect, you start all over. Found out the hard way when I changed an O2 sensor & reset the computer just before I took it in for state inspection. They couldn't pass it in open loop mode. They had the darn thing for two days before it passed.

Joel

Disconnecting the battery on my 2002 throws the system in open loop for ~50mi of driving. Everytime you disconnect, you start all over. Found out the hard way when I changed an O2 sensor & reset the computer just before I took it in for state inspection. They couldn't pass it in open loop mode. They had the darn thing for two days before it passed.

JoelWho's "they"?
I cleared a code and didn't wait long enough and all I got was my sticker scraped and a letter to keep in my glovebox saying I failed because this and that weren't ready (in case i got pulled over). I had a week or 10 days to get it re-inspected. All it took was about 100 miles of driving for everything to be ready.

Who's "they"?

'They' = my local isuzu dealer. The only one remaining in the Buffalo area. Per NY State law now, in order to pass state inspection, everything has to be OK from the OBDII port. Not ok means you dont get a sticker. Your 'personal' OBDII scan and VIN# are wired to and kept on record in Albany.

G/luck
Joel

'They' = my local isuzu dealer. The only one remaining in the Buffalo area. Per NY State law now, in order to pass state inspection, everything has to be OK from the OBDII port. Not ok means you dont get a sticker. Your 'personal' OBDII scan and VIN# are wired to and kept on record in Albany.

G/luck
JoelIt just means when you go back and everything is ready and it passes you do get a sticker. You can drive without a sticker as long as you have the inspection waiver in your vehicle and it hasn't expired... per NY State Law.

Yeah but if everything is not ready, you don't get a sticker. You'd never know aside from plugging in a higher dollar code reader that you are in open loop mode. The state does put a cap on the amount of money that it would take to fix the issue (dunno the $ amount), for that particular session. So you spend up to the cap, still no pass, still no sticker. Waiver runs out after the time limit (not sure how many days) & you go thru the whole cycle again.:banghead: It will eventually get to the point you wont be able to afford to drive a 1996+ hi mileage car! Most mom & pop shops cant afford the equipment required to read/record/submit your OBDII data to Albany.

Joel

In my case I knew what the problem was and fixed it but just didn't wait long enough. :banghead: I thought I had driven around enough but... oh well.

Did you notice that the new stickers now have a date range on them? You now have until the last day in the range (1-10; 11-20; 21-31) to get it done. I guess it's supposed to spread out everyone's inspections so that there isn't such a big rush during the last week of a month.

Yep, just got the van inspected yesterday. It's got one of those funky new stickers on it :uhoh: .

Joel

You guys still have stickers?

We got rid of those years ago. Now there is talk of even getting rid of emissions inspections all together. They figure most of the old higher pollution cars have been scrapped by now.

You guys still have stickers?

We got rid of those years ago. Now there is talk of even getting rid of emissions inspections all together. They figure most of the old higher pollution cars have been scrapped by now.NY actually just started State-wide emissions testing last year. It was supposed to start in 1998 but last year was when they finally got it up and running. Where I am (and Joel as well) it's just a functional check of the emissions equipment. Down-state however, vehicles are tested at idle or on the dyno with a tail-pipe thingamajiggy.

NY actually just started State-wide emissions testing last year. It was supposed to start in 1998 but last year was when they finally got it up and running. Where I am (and Joel as well) it's just a functional check of the emissions equipment. Down-state however, vehicles are tested at idle or on the dyno with a tail-pipe thingamajiggy.


Yea, I'm in NY as well and I'm not a big fan of all this. It is an inconvenience. I guess it is for a good cause, but it irks me that a lot of the country doesn't have to do it like this.

Truck is definitely returning to normalcy; already getting MUCH better mpg. A tank just a week ago, same driving, same route, same time of day, and same gas station gave barely 14mpg.

This last tank averaged 18mpg and that's with longer idling.

Driving the truck is a pleasure again, rather then something that was feeling more and more like it was losing complete umph.

FYI, if someone keeps good track, and notices their gas mileage dropping steadily, and you're at or over 80-100k miles, it's probably your sensors.

Mine was dropping steadily since June, very slowly taking the umph with it.