04 TB LT all options

[jozuah]

04 TB LT all option packages, Running boards removed (it was that or buy a suit and i "aint" buyin' no suit) has 53K miles and i use 89 octane 10% Ethanol fuel in Iowa.
I have changed the 02 sensor on the E/manifold due to a code and was wondering about changing the other if i have noticed a fuel economy change ,, i get 13.8 in town stop and go driving no more than 50 MPH for any length of time. and i get 17 - 18 Avg. MPG on the interstate ( semi-hilly 75-80 MPH). Last note for anyone who may wonder, the S.E.S. light flickers for an instant about 5 -7 miles after i start the truck for the first time during the day,no hard codes (im thinking it's at that point it switches from closed to open loop)..
should i replace the downstream one ?
TIA
Joz

[srbianats]

Originally Posted by jozuah

04 TB LT all option packages, Running boards removed (it was that or buy a suit and i "aint" buyin' no suit) has 53K miles and i use 89 octane 10% Ethanol fuel in Iowa.
I have changed the 02 sensor on the E/manifold due to a code and was wondering about changing the other if i have noticed a fuel economy change ,, i get 13.8 in town stop and go driving no more than 50 MPH for any length of time. and i get 17 - 18 Avg. MPG on the interstate ( semi-hilly 75-80 MPH). Last note for anyone who may wonder, the S.E.S. light flickers for an instant about 5 -7 miles after i start the truck for the first time during the day,no hard codes (im thinking it's at that point it switches from closed to open loop)..
should i replace the downstream one ?
TIA
Joz

When was the last time you checked your plugs and wires? SES light flickering could be misfires. A plug could be going or wire has a crack.

[jozuah]

Originally Posted by srbianats

When was the last time you checked your plugs and wires? SES light flickering could be misfires. A plug could be going or wire has a crack.

Thats a great suggestion, ill look into that asap. i figured that a misfire with OBDII would store a hard code but after reading this post i remembered that its not right, ill scan it and see if i have a misfore detection and go from there.

thanks again

joz

[ScarabEpic22]

There are no plug wires on the I6 or the V8s available in TBs. They use a coil-on-plug design, but check the connections to the coil packs too. You have to remove the pack to get to the plug.

[jozuah]

Originally Posted by ScarabEpic22

There are no plug wires on the I6 or the V8s available in TBs. They use a coil-on-plug design, but check the connections to the coil packs too. You have to remove the pack to get to the plug.

i noticed that today, plugs are greyish and the gap is still correct.

there are no codes stored in the ECM and my monthly onstar report had nothing also

*stumped*
joz