Sluggish D-Max

[Traveling Man]

What a forum. You guys have a wealth of knowledge. I need to tap some of that knowledge and ask a newbie question.

Picked up my D-Max on 14 May. I now have 600 miles on her (him?). Power is great around town and during stop and go. When accelerating on an entrance ramp to highway speed (65-70) I have no power. I have to hold the go peddle to the floor and it still takes a long time to get up to speed. Once at speed I can back off and it crusies great. I have also noticed that when passing at 65-70 mph acceleration sucks. Again I have to mash the peddle to the floor to accelerate slightly.

Question: During the breakin period is the D-Max limited to prevent damage to the engine and tranny? Am I describing what you guys call "limp mode"?

Love the diesel though! Great Forum!

KD

[mackin]

Traveling Man,

Welcome ........
Your immediate questions .....

1) During the break-in period is the D-Max limited to prevent damage to the engine and tranny?

: No

2) Am I describing what you guys call "limp mode"?


: No,
It wouldn't be cool around town if it was limping .........

Limp mode is a tranny fault condition .......

Now is it downshifting at them highway speeds?

Or just lugging in overdrive?

You should check, can you believe it, for PCM,TCM updates ..... At ===>http://vci.ecomm.gm.com/vci/ follow the instruction when you get at page . It's a vin thing ........

There has been a few complaints of under power and a reflash as needed corrected it ........I would think this would be a start for you, plus let her (him) break in a little ......... Then decide if something really ales Your MACHINE .......

Me I'd just add a shot of "JUICE" but that's just me ... LOL

Good luck
MAC
:D

[ 05-21-2002: Message edited by: mackin ]</p>

[Kennedy]

Traveling Man,

First, the handle sounds familiar???

As for sluggishness, I guess I would explain that to the dealer and have them scan it for codes. This would be the first indication of a problem. Looking at the MAF (mass air flow) rate at idle should be in the neighborhood of 40g/s. If this is low (trust me I know first hand about this) it will run like a big turd. We swapped MAF sensors only to fond that the problem was with the air box lid. The modification that I THOUGHT was helping me, was actually hurting me as it altered the airflow across the sensor...

[Traveling Man]

mackin

It does not "hunt" through the gears at highway speeds. Once I GET up to speed everything runs smooth until its time to give it a little petro to move past a big truck. Pushing the peddle down does not cause a downshift and it lags in overdrive. During acceleration on the entrance ramp it feels as if I have 40K loaded on the hitch.

I did the VIN scan thing and provided a copy to the dealer prior to taking delivery. I did not see any PCm,TCM updates.

KENNEDY

I'll have the tech scan for codes when I take it in for 1K oil and diff fluid change.

Thanks

KD

[MNBowTie]

Traveling Man,

Just wondering, if this is all time, or does this this condition appear before full operating tempature? I would try a a different fuel sorce. I have also noticed with winter blended fuel and a cold engine, mine sometimes acts the same way.

[SoMnDMAX]

Plugged fuel filter? It only takes one bad tank to FUBAR a fuel lilter...

Plugged air filter? Can you see it smoking (black) badly?

[Carli_max]

Hey Traveling Man, Welcome to the forum!!

What part of Central NY are you from?? Is your truck up to normal operating temperature when this occurs?? If you live in Central NY, it's been down right cold the last couple of weeks. If your not far from your house when you are getting on the highway, then it will be somewhat sluggish until it heats up. Diesels are cold blooded!! Also when really cold the allison doesn't want to go into 5th. Let me know if your anywhere near Marcy. If so we can compare rides!

Carmen

[Traveling Man]

MNBow Tie & SoMnDMAX

This happens all the time, cold, warm, wet, dry. I have not noticed any black or even gray smoke from the tail pipe during the time.

Carli_Max

I am in Cicero. I was just in your neck of the woods yesterday (Holland Patent). As mentioned above this happens all of the time. It seems the engine can't get enough power to the allison to make her go. As for shifting into 5th, it does that fine. Getting it to down shift from 5th to 4th at highway speed is another story. I push the peddle to the floor and she just won't drop down.

KD

[Carli_max]

Traveling Man
Just went through Cicero this morning, on my HOG. I work in Liverpool. Could be the Fuel Filter as SoMnDMAX said. Have you tried running the truck with the T/H button on?? Maybe you might try that Tranny reset procedure! 50MPH and down shift to 1ST a couple times. Then drive it like you stoled it after that! Hope things work out for you.

[Kennedy]

To echo some of the comments here, I would look at coolant temp. The factory gauge should hit about 1 notch short of vertical. Now just because IT hits operating temp, does not mean the sensor for the ECM does so that would be my next check.

I have also heard of a party who discovered his Dmax was missing a thermostat in one hole, and this kept him cold...