therock

iTrader: (2)

I have heard that burning antifreeze will damage o2 sensors.

Problem = bad gas mpg after heads replaced.

We have a reg cab 04 Silverado w/5.3 that the water pump went out on, got hot and the heads cracked.

They were a small enough cracks the antifreeze would consume at a quart a day or so. No smoke but stinky.

This went on for weeks while while we fought with the extended warranty Co for coverage. Long story but we got them to cover it.

The o2 sensors were not considered by the dealer for I'm sure.

Now the truck gets a crappy 12 mpg highway.

Any truth to the o2 sensors & antifreeze possible damaging thing? A novice HPTuners owner I would like to ask what, if I can scan and log and tell by the numbers. Would some trims look really off?

We need help finding the gas guzzling problem.

budhayes3

iTrader: (19)

Yes, antifreeze can and will contaminate O2 sensors and could cause incorrect readings...if everything else from the head swap is OK (no vacuum leaks or anything like that), there is a good chance that one or both of your O2 sensors have become contaminated with antifreeze

therock

iTrader: (2)

Thanks, We are shopping for sensors.

I take it all four would be the way to find out? It's been a while since I've been under there, two pre and two post cats sensors? Or a single after the Y?

Rock auto .com has Bosch units for 43.79 each. The same p/n goes in both sides.
They have 2 NTK's left in stock but are 81.79. Heh!

budhayes3

iTrader: (19)

There are 4, but you could start out with the front two, as the rear O2 sensors only account for something like 1% of fueling since their main purpose is to monitor the cats.

I don't like Bosch parts, but I've seen more than one Bosch O2 sensor installed without any problems.

AKlowriderZ71

iTrader: (22)

I would recommend replacing the front o2's, let the rear ones be unless you start throwing cat efficiency codes.

therock

iTrader: (2)

What other brand of o2 sensors are recommended besides the high dollar NTK's?

AKlowriderZ71

iTrader: (22)

I have never had troubles with the Bosch.

hirdlej

iTrader: (31)

Just use Delco ones and call it a day.

budhayes3

iTrader: (19)

Denso electronics are of the highest quality, but also the highest price. For $44 each, I'd give the Bosch a shot. I've had problems with other Bosch electronics (relays, VW cap and rotor, spark plugs), but haven't heard of any issues with their O2 sensors.

Dewey

iTrader: (1)

I too have been warded away from bosch electronics but for half price i say give it a shot.