1997 K3500 454 Work Horse

[MrMarty51]

The 93 K1500 I had, at 70 mph, that thing would kick down on the slightest up hill grade, if the cruise control was set, if there was any head wind or breeze, it was much worse.
I could run the throttle with My foot, maintain speed on some pretty steep grades and it would not kick down except for on the steepest grades. Manual running the throttle increased fuel mileage greatly too.
You might try that next time out.
Short shots of starting fluid around vacuum manifolds, base of TBI, etc. will let You know immediately of there is a vacuum leak.
An ex coworker had a 454, His son had a 6.5 both about the same years. He swore that the 454 pulled way better than the 6.5. I always thought, a little work on the 6.5 might make a difference.
About the best fuel mileage He got with the 454 was in the 14 mpg area and less.

 

[tanman_2006]

If I drove by foot the torque converter still only locked on down hill and unlocked as soon as I was on flatish ground. Doesn't feel right for a 4l80 and 4.10's with a big block to be running without the TC locked 90% of the time. We had a 5mph head wind. The issue didn't start until the cel came on.

 

[Will L.]

No clue what the specs are, but maybe look into tps and how
It relates to the code. What’s the code?

 

[tanman_2006]

Like I said earlier. I need a scanner

 

[THEFERMANATOR]

You can buy an OBD2 dongle and use the torque app if you're just doing obd2 and scanning codes. The CKO TECH2 is nice if you're doing alot of GM stuff, and it does EVERYTHING on covered models(most everything from 92 to 2013 with a few exceptions from 11-13). The MAF sensor is KING on that system, and controls almost everything from idle, to shift points, lockup, you name it.

 

[tanman_2006]

After the lml is gone I will either buy a crew cab 6.5 or a 6.0 so I'd say the cko would come in handy.

 

[MrMarty51]

You can buy an OBD2 dongle and use the torque app if you're just doing obd2 and scanning codes. The CKO TECH2 is nice if you're doing alot of GM stuff, and it does EVERYTHING on covered models(most everything from 92 to 2013 with a few exceptions from 11-13). The MAF sensor is KING on that system, and controls almost everything from idle, to shift points, lockup, you name it.

The Torque app is a real good system, but, only works with android.
Not as many functions as torque pro, but I have one called four stroke on My I phone.

 

[tanman_2006]

Here are the codes, I also have low voltage now, battery tests good though

 

[WarWagon]

What @THEFERMANATOR is saying is to clean the MAF...

Looks like you are hunting down grounds, tracing the positive cables, cleaning fuses, and testing ignition switches, to fix the low voltage FIRST! Low voltage screws up ECM's including ghost codes. With the TCC not locking up I would also verify the brake switch is working properly. (Although codes alone could do it.)

 

[tanman_2006]

Heading in for an alternator, it locked up at start up this AM. Hoping that gets the voltage fixed.

Thinking maybe the ecm temp sensor could have failed causing the engine to run rich and trip the O2 sensor and kick out the tcc.

 

[WarWagon]

Don't confuse the heater circuit for the "sense" of the O2 sensor. No heater -just takes longer for O2 sensor to start working.

Cold engine warm up mode with no tcc comes to mind.

 

[THEFERMANATOR]

If its running cold, you won't get lockup. Looks like you needa tstat(or a cts issue), most likely an O2 sensor, and either an iac or a vacuum leak.

 

[THEFERMANATOR]

Don't confuse the heater circuit for the "sense" of the O2 sensor. No heater -just takes longer for O2 sensor to start working.

Cold engine warm up mode with no tcc comes to mind.

Without a working O2 heater, a downstream O2 will not work properly unless you're pulling a good load on it. And at idle it will stop working.

 

[tanman_2006]

New alternator fixed my voltage. Cleaned the maf and swear I gained 50hp lol. Sprayed a can of sea foam through the intake. Found a small crack in the upper intake, sprayed it with ether and the engine didn't rev but still will need replaced soon.

The engine runs around 190 according to the dash gauge.

 

[tanman_2006]

 

[tanman_2006]

 

[tanman_2006]

So do I clean or change the IAC? Where exactly is it?

Just change the O2 sensor or is the heating part seperate?

I'll take an IR to the t stat housing. Is 190 too cold? I thought 160ish was the temp goal for lock up.

 

[tanman_2006]

Also where is the ops located?

 

[THEFERMANATOR]

190-195 is about where it should run. Lockup isnt until about 145. You need to see what the pcm is seeing for coolant temp. The plugs are known to corrode after people work on them. They get coolant in them, don't spray em out, and it rots the pins out. So make sure the pcm is seeing its up to temp. The iac should be in tbe throttle body. It's probably a good idea to pick up a new gasket, pull it off, clean the whole throttle body really good, and put it back together. I would also put a new pcv valve in it. I've seen em get carbon caught in them, stick open, and cause a high idle.

And if you do a tune-up, remember the stock dustributor is plastic, and is VERY common for it to crumble when you take the screws out that hold the cap on.

 

[tanman_2006]

On the inside of the intake? That's convenient lol.

What about the O2 sensor? Clean? Replace? Or get the other codes first and see of it corrects its self?