Throttle Response loss

[Milana]

Hi Everyone,
Looking for tips on an escalating issue that has the mechanic vexed. I have an 04 V8 LTD with 150 000 KM. The servicing schedule has been followed religiously from day 1. ( All fluid changes, belts,filters, plugs have been changed/replaced)

A few months ago I noticed a power loss while attempting to make a left turn. The truck barely crawled through the red light and took another 6 seconds before it built up enough momentum to get to merge speed on the highway.
Several months later, the same thing happened again while making a left turn. The truck would not move past a crawling speed...and it takes about 6 seconds for it to build up momentum to get up to 60 kmph/40 mph. (Flooring the truck makes no difference)

The problem now is that this intermittent issue is getting well more pronounced in stop and go traffic. Any ideas on where to start the trouble shooting issues.

I do not think the MAF and the IAV are suspect given that the rpms are stable. There never has been any tell tale signs i.e rpm fluctuations prior to and during
these event failures. The only constant I have is now is stop and go traffic = 6 sec intermittent throttle response delay.
"No codes and lights"

 

[awdjunkies]

:welcome: to T4R.ORG ... Have you kept record of when this happens, which gas station you went to? Fuel Filter(Even though you say everything has been religiously replaced)??

Just for the heck of it, try cleaning the MAF...

What type of oil?

Have you ever seafoamed it?

How are your Cats? Your Oxygen sensors?

 

[lehiguy]

Based on your description, I would say fuel delivery issues. No codes means the sensors are good.

 

[RunnerAK]

Sounds almost like your traction control kicking in. Mine did something similar today while turning left at an icy intersection, the traction control took over and basically bogged the engine down for several seconds, causing me to barely creep through the intersection.

 

[NJshadow93]

When was the last time the transmission fluid was flushed/replaced? Sounds like it might be low on fluid and the transmission is slipping.

 

[satanos6668280]

Sounds almost like your traction control kicking in. Mine did something similar today while turning left at an icy intersection, the traction control took over and basically bogged the engine down for several seconds, causing me to barely creep through the intersection.

+1 I concur. You may have a speed sensor going out or a speed sensor wiire starting to break. Best thing is hook up a scantool capable of abs/trac data stream and watch each wheel speed sensor while the truck is acting up. Empty parking lot or field and just turn in circles or start and stop whatever you can do to make it act up safely out of traffic. Readings 1-3 or so mph difference are normal more that and the odd man out is your problem

 

[4runner55]

Throttle control motor failing. Had the same problem with 01 Tundra 4.7 V8.

 

[Atlanta_man]

Traction control kicking in would have turned on the light on the inst panel.
Happens to me if the turn is over a lot of bumpy's and trying to accelerate through the curve.

Worse is on the rare icy day we have in Atlanta - you get half way into the intersection with oncoming cars and the motor shuts way down. scary

 

[Stuck CAPS]

Hi Everyone,
Looking for tips on an escalating issue that has the mechanic vexed. I have an 04 V8 LTD with 150 000 KM. The servicing schedule has been followed religiously from day 1. ( All fluid changes, belts,filters, plugs have been changed/replaced)

A few months ago I noticed a power loss while attempting to make a left turn. The truck barely crawled through the red light and took another 6 seconds before it built up enough momentum to get to merge speed on the highway.
Several months later, the same thing happened again while making a left turn. The truck would not move past a crawling speed...and it takes about 6 seconds for it to build up momentum to get up to 60 kmph/40 mph. (Flooring the truck makes no difference)

The problem now is that this intermittent issue is getting well more pronounced in stop and go traffic. Any ideas on where to start the trouble shooting issues.

I do not think the MAF and the IAV are suspect given that the rpms are stable. There never has been any tell tale signs i.e rpm fluctuations prior to and during
these event failures. The only constant I have is now is stop and go traffic = 6 sec intermittent throttle response delay.
"No codes and lights"

Try cleaning the TB, and seafoming next oil change. IF that doesn't make a difference, it could be the butterfly valve not being able to open all the way, or even something in the drive train.

 

[BCfish]

Could even be fuel pump too