Dangerous delay in acceleration of GL320??
My wife told me she got pretty scared the other day when she went to accelerate out of our neighborhood and onto a busy street and there was a lengthy delay in her GL320's response to her flooring it.
I've noticed it too: You press on the accelerator and after what seems like a 1+ second delay the vehicle jumps like a bat out of hell. Impossible to modulate, impossible to get rid of the delay. You either have to drive like a grandma or get shot like a bullet.
Who else has noticed this and has anyone tried to fix it?

What some of us have come up with is, half throttle at the start as opposed to mashing down on the pedal actually gives some better off-the-light because instead of waiting for the torque converter to engage and the turbo to spool up, it allows the engine itself to give something to the equation. Once things start rolling, swiftly but smoothly add lead to the foot and you should get a smoother start followed by rapid acceleration. (Rarely do I have to put in any more accelerator once the maneuver's started as the torque converter and turbo come on line and add the boost I need. Now, as for cowbell, I do need more of THAT ...)
Your next option is the two-footer option, which is where you spool the RPMs up to the 1700-2100 range with the right toes, while holding the honey back with the left ones. This should produce that neck-snapping start we're all used to from normally aspirated engines.
My wife told me she got pretty scared the other day when she went to accelerate out of our neighborhood and onto a busy street and there was a lengthy delay in her GL320's response to her flooring it.
I've noticed it too: You press on the accelerator and after what seems like a 1+ second delay the vehicle jumps like a bat out of hell. Impossible to modulate, impossible to get rid of the delay. You either have to drive like a grandma or get shot like a bullet.
Who else has noticed this and has anyone tried to fix it?
The easy fix, is to wait for a reasonable space in traffic, and not have to enter like an ******* at full throttle.
BTW GL320 is my Grandma's whip too.
Half throttle at the start yields anemic acceleration, and I can't see my wife brake-torqueing.
The fact that she would even need to consider either of those options for some off-the-line pep is a joke.
I've been driving diesels in Europe for over 10 years and my truck is a diesel, never had a vehicle do this.
Last edited by str8line; Jul 30, 2007 at 12:24 AM.
Last edited by Danno4x4; Jul 30, 2007 at 03:52 AM.

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The fact that she would even need to consider either of those options for some off-the-line pep is a joke.
I've been driving diesels in Europe for over 10 years and my truck is a diesel, never had a vehicle do this.
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My wife told me she got pretty scared the other day when she went to accelerate out of our neighborhood and onto a busy street and there was a lengthy delay in her GL320's response to her flooring it.
I've noticed it too: You press on the accelerator and after what seems like a 1+ second delay the vehicle jumps like a bat out of hell. Impossible to modulate, impossible to get rid of the delay. You either have to drive like a grandma or get shot like a bullet.
Who else has noticed this and has anyone tried to fix it?
depress accelerator all the way for about 10-15 seconds
release pedal and turn key to position 0,
leave the key in for a minute to two or three minutes
I'll try that, but I wonder if that affects the shifting only and not the response from a standstill. I'm waiting to hear from the dealer to see if they have a remedy.
STP
Again, I'll keep you guys updated.
Turn the key to the "off" position (don't remove the key), then release the gas pedal.
Note: I have never noticed anything from doing the re-set procedure in my car. If it has ever done anything, it was subtle at best. Maybe mine is just always ready, like a cocked weapon.
Turn the key to the "off" position (don't remove the key), then release the gas pedal.
Note: I have never noticed anything from doing the re-set procedure in my car. If it has ever done anything, it was subtle at best. Maybe mine is just always ready, like a cocked weapon.

I've always done it by releasing the pedal then turning the key. I'll try it the other way and see if I get the same results.

From the service bulletin: Recommends not using the two pedal technique.
Aug 21, 2007 S-B-27.00/101 MY All Models All With Transmissions 722.4/5/6/9 Do Not Operate the Accelerator Pedal and Brake Pedal Simultaneously. Heats up transmission, may damage torque converter/transmission, reduce service life
The fact that she would even need to consider either of those options for some off-the-line pep is a joke.
I've been driving diesels in Europe for over 10 years and my truck is a diesel, never had a vehicle do this.[/QUOTE]
I too have been driving diesels for a while (25 years over 800,000 miles) going back to the pre-turbocharged days. All of them were American made, in large pickups except for the 1981 Toyota pickup, when I was in college (had to turn off the AC when pulling a hill). All of them had the notoriety of turbo lag, especially if you floored it. This includes my 4 month old 2007/2008 Duramax that has common rail injection and a variable geometry "smart" turbocharger with computer controlled turbine vanes. This is supposed to reduce the lag time but it is still there. Once it spools up, it takes off like a sports car and is scary fast.
Ford's new 6.4 Twin Turbo has a smaller 2nd turbo that is designed to spool up at low RPM's and eliminate the lag and it does seem to work well. This is a common age old problem for turbo-diesels, and they are all trying to reduce or eliminate it through technology. Kind of like shutter lag on digital cameras.
When I test drove the GL 320 and ML 320, it wasn't noticeably worse or better than what I am used to driving. Since my wife has been driving a diesel for 10 years, I don't think she will have a problem with it either. I think it is something you have to be aware of and comfortable with. It is a compromise for having a 3.0L engine that can make this much power and yield this kind of economy.



