the pulley is a silly bandaid. The new alternator is the way to go.

 

My ECSB is also a 26 gallon tank.

 

Roger, I only went 250 mi on this last fill, but had ~1/4 tank left. But, I forgot if it was totally topped off to begin. It figured to 14MPG.

 

As I mentioned on the phone the other day, the winter blend gas is good for about a 2-3 mpg loss

 

must be a nortern thing with different blends i havent seen a change with mpg past 3 weeks.

so a 160 stat.. and the tune knowing its there will have a no negatives factors on the mpg correct?

 

I don't think the tune is causing a problem....

the ECT spark table there is no change between ECTs of 149*-203*

the commanded fuel mixture table is the same between ECTs of 158*-284*

As for entering Closed loop, the closed loop enable table is low enough to accomodate the 160* stat.

Also the closed loop enable temp is set to 167*...


All of those are stock values...

 

Corey, any ideas?
I might add when I changed my bro's plugs in his '02 Silvy @ 70 or 75k, they were flat out hit. He mentioned he has the original O2's in his truck. Then all of a sudden,this occurs --> I'm of my original plugs w/. 67,800 miles. Only 1 was ever replaced, & that's cause I broke ceramic when I dropped a plug while doin headers. $8 mistake.
So I plan to replace w/. some new AC Iridiums since I'm overdue. Also, RT Bank 2, Sensor 2 ( the rear O2 on pass. side) has been replaced cause I thought it faulty when SES light 1st came on some time after header install.

So now, even if I delete code on O2, it comes back.

My plan is new plugs: $64 total
New O2's. --> 4x IDK how much these are gonna run me? I'll guess $40 each.

I figure when all done, I'll have ~$200 or so into it. If both are overdue, hopefully this will help.

I hope this minor tuneup will help.

 

Well before you spend alot of money, pull the plugs and check for damage and propper gap.

then log your O2 sensor voltages.... they should osciallate (meaning, go up and down).... they should osciallate about the same, if one flat lines and the other is moving, if that pattern repeats then you have a lazy one... which would need replacing...

Also replacing all 4 is crazy, just replace the front ones...

Since you have HPtuners just delete the test for the rear O2 sensors.... go into the diagnostic section of the tune, then Processing Enablers, then set everything with sensor #2 to Not reported.

 

On a side note. IMO these motors are designed to operate at higher temps than the old school motors, FI being an exception... I would never put a 160 stat in my truck, maybe a 180 if i was FI....

 

I replaced my stock 02s at 154,000 miles with brand new Denso units (the best you can buy) and it made NO difference whatsoever. with your low mileage don't even consider wasting the money on new o2s unless you are actually seeing it not switch on your HP tuners as Corey said.