Don Odom

I do normally run regular, I just thought it might balance out the junk. I have had vehicles in the past that actually ran better on premium but this is the first time I've put any in the Tahoe.

Don Odom

I normally don't use premium or Walmart gas either. The Walmart part was extenuating circumstances. Never again. I'll find another way if it's crucial and I'm broke.

I went with the premium to balance out the junk gas. Probably my thinking was affected also by vehicles I've had in the past that would run better on premium. Strangely enough, the VW was one.

in2pro

Many import and performance vehicles do require the premium grade fuel for its higher resistance to pre-detonation at higher compression, as do the NBS's that have been modded with a chip... But if you are an every day driver with a
non-modified Tahoe/Suburban or truck engine, the 87 octane is all that is needed.
Additives used regularly I believe, do help with keeping injectors cleaned..

I hope the fresh tank of gas resolves the issue you are seeing...

tech2

the reduced power mode message will set when the ecm detects a problem with the TAC system. Bad fuel will not cause the system to fail this logic check and set a code.


I'll bet you have an intermitant problem that will re-occur.

The system ran and passed its logic check after the battery was reconnected.

I'm surprized that disconnecting the battery cleared the dtc and that nothing was stored in history.

SWHouston

I'm really surprised how Don's problems mimic those I've had.

I use Sam's Club gasoline, and it seems that Wallmart isn't the only fuel which may be in question. After my tuneup, it was suggested that I use an additive and choose Lucas. I'm now feeding it to two other vehicles as well. If anyone has something to say about the Lucas product, I'd sure like to see it.

Don, I'm not sure if you know this but...
My Burb has most frequently displayed the "Reduced Power" message, when I first crank it up (after a thorough cool-off). I've found that if I just let it run a minute or so with the displayed message, then, shut it off, it usually then cranks properly and the message is not shown.

I know that's not a fix, but it sure has helped.

Don Odom

Thanks for the info. I drove 35 miles today with no error messages or warning lights. Keeping my fingers crossed. I will driving 90+ miles one way in 2 days for a job interview so I'm keeping my tools on board in case I need to perform a reset.

wrxnut25

I had this same problem happen to my 2005 Tahoe yesterday, I've found plenty of threads regarding this issue, but no one seems to post the determined cause of the problem after they had it fixed.

Anyway, took my rig to the dealer (my wife's uncle is a service mgr.) and they told me it's probably a bad battery. I'm having the battery replaced this afternoon, I'll report back whether or not that resolves the issue.

Don Odom

Another update, after doing the battery unhook off and on for months, in January I had the money and bought a new throttle body and installed it. (No longer unemployed, I started my own handyman business-woohoo!)

No problem for a couple of days then it started again....Unhook battery, warnings clear off, drive again until next "trip out"-which might be 2 minutes, hours, days, or weeks. Then one day, it refused to clear off....unhooked battery and didn't reattach til next morning-no problem.....this cycle repeated, some days it would clear, others it would not, and the days of course when nothing was wrong. Then one day it wouldn't clear even with overnight battery disconnection so I carried it for code check to O'Reilly's, a local mechanic shop, and chainstore Tuffy's tire/oil change shop....I was told:
(in respective order)
1. change throttle body
2. problem is either throttle body or accelerator pedal position sensor...unclear without further diagnois.
3. use fuel system treatment & change spark plugs and wires(I did, no change)...I called back and was told "well that was no guarantee, that's where we would have started since it can't hurt).

(Stupidly, I never thought to ask what the actual code was).....Now for 2 weeks no warning messages, running like nothing was ever wrong. I'm about ready to trade it in while nothing is happening but I really don't want to pass my problem off to someone else.....and we do like the vehicle's comfort and room.

When you search online there are dozens of threads on this subject with dozens more chiming in on the original threads with the same symptoms. I'm just rambling now so I'll shut up until something new occurs.

SWHouston

Don,

First of all, let me congratulate, and wish you the best in your new venture !

I too have done that, except that I went for Small Engine Repair (lawnmowers/motorcycles/etc). It was just something to take up my time and provide a little income, while waiting for a more lucrative employment opportunity.

Yet again, I have to comment on the similarities (repairs) which I had done to my Burb as you. However (still dealing with the problem) I took mine in for a general tune-up, trying to get better mileage. Injector cleaning, and a new set of wires was done.

Surprisingly, I have not seen the Reduced Power message "so far". So, after over $1000 repairs and time down for that, it may be fixed. I do have a Check Engine light on now, but, it has not inhibited the operations so far.

Thanks for your update, and I'll try to get back for one of my own, after I get it to the shop.

Good Luck,
S.W.

postb8822

Had the same issue on my 2009, GM extended a warranty on the throttle body position sensor to 10 yrs 100,000 miles. They will also reimburse you for the repair you paid for if you have your documents.

Search for 10-Year Special Coverage 11273*

I have the letter somewhere but I am pretty sure it was back to the 07 models too.

In either case, I think the throttle body and sensors are the cause, it was the only thing I changed on mine and the problem has not come back at all.