Poor throttle response Denali after long trip

[scottg918514]

I just got back from a 4000 mile road trip to Utah and back (VA). Since getting back I've noticed poor throttle response. The engine seems to bog then kick in abruptly. I'll be pushing down on the accelerator pedal and rpms are around 1.5K and not moving much, then boom, 3.5 k.


Truck is a 2007 Yuk XL Denali with a hair under 80K on od.

Did the computer get "fooled" with all the highway miles? Or is my throttle position sensor kaput?

Anyone else encounter similar symptoms?

---------- Post added at 01:16 PM ---------- Previous post was at 01:13 PM ----------

No codes BTW.

 

[yates ™]

It could be the TPS or possibly a dirty MAF sensor.

 

[JonnyTahoe]

What were you getting for mpg?

 

[scottg918514]

What were you getting for mpg?

Did pretty good on trip. Going out avg 16.5, but had a bike on roof and no fairing (and headwind). Coming back, 18, no bike on roof, removed bike trays and added fairing (tailwind).

Since back, it's gone down some, but as expected in city driving. I didn't reset, but I'd say avg is still in the 17's.

I'll check tonight.

 

[HUMBL57]

Bad fuel maybe? You check the air filter lately?

 

[scottg918514]

Bad fuel maybe? You check the air filter lately?

Bad fuel, maybe, but several tanks later, same issue. New K&N air filter a few months ago.

Cleaned MAF, no codes

Thinking TPS, or the accelerator pedal position sensor.

Someone out there must have had this issue before.

Push pedal nothing, then acceleration kicks in abruptly, kind of like a turbo lag feel.


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[Sdotbun]

Fuel cleaner and a new air filter helped me.

 

[scottg918514]

Put in Royal Purple MaxClean in April, new air filter too. I moved my pedal position today (adjustable pedals ) a couple times, might re-sync the pedal position sensor, if that is the culprit. Otherwise, I might replace that sensor first and if no improvement, I'll replace TPS also.


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[scottg918514]

Tracking a possible cause. I think the poor throttle response only happening when the engine goes into energy save mode.

Or, when then voltmeter goes from charging 14, to maintaining 12-ish. From what I understand, this is minor fuel saving mode where the alternator isn't drawing as much off the engine.

I'll keep an eye on it.


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[okfoz]

I have seen carbon build up in the exhaust... I assume you already tried putting it in low gear and standing on the throttle to blow out the carbon...

I drive like a Grandpa, (I actually average 18.5 as indicated by the dash) in my LTZ (wish I had the Denali Engine). Every few weeks or so I have to really get on the gas, to clean out the carbon. If I do not it starts eating into my power and my MPGs

John