Why wont my VT go hard when I accelerate??

[Full Spectrum]

Holden and Ford Dealers have this annoying thing with cars that come in, They reset everything. The BA used to hit 150 easy in 2nd gear, After ford struggled to get 145. What they do is piss people off. XR6t's go in and come out slower, Same with Holden...

 

[danja]

No, no little orange label under the hood at the front... and yes they charge...

Throttle Body ($100 to clean and adjust)..<< this is exactly how it's written on the bill...

It's fair enough to charge for cleaning the TB (though $100 is a bit steep... it's a $2 can of carby cleaner, and a few sprays inside, takes about 5mins... Even if the remove it from the engine at clean if properly it's still less than 30mins.

Anyway, that aside the idle is controlled by the computer, you can't adjust it without re-tuning the computer, which I've never heard of as being part of a standard service.

If it were me I'd take the bill back to them and tell them where to shove it

The sticker I'm talking about is the same as the one at the bottom of this pic, the orange on on the black cover over the radiator. Pretty sure it tells you the idle

 

[pablo]

"Anyway, that aside the idle is controlled by the computer, you can't adjust it without re-tuning the computer, which I've never heard of as being part of a standard service."

After I had put back my throttle body after cleaning it and the IAC valve,
I had the engine idle a bit on the slow side. Went to see a friend who is the service manager in a holden dealership, he hooked up the Tech2 to check the electrics over, then, with a screwdriver, he re-adjusted the base idle screw on the throttle body, still reading from the Tech2. I think he disconected something off the motor as well while this was done. This brought the idle back up to specs.

 

[GMHVF6]

bahaha thats an old pic of my engine bay, and yes that sticker does say idle speed

 

[Ozzie]

Just a quick update to this old thread....

I changed the exhaust to a 2.5" sports system, Upon examination of the old exhaust I found it did have a leak just before the rear muffler.

I also changed the CAI setup I had to the standard box modified with an internal pod CAI, I also installed the o2 sensor inside the pipe for the CAI.

Big Difference
I now have power the back again and its hard to accelerate around corners without spinning.

Still sluggish up hills from start though but I guess it is a 6 afterall

 

[danja]

After I had put back my throttle body after cleaning it and the IAC valve,
I had the engine idle a bit on the slow side. Went to see a friend who is the service manager in a holden dealership, he hooked up the Tech2 to check the electrics over, then, with a screwdriver, he re-adjusted the base idle screw on the throttle body, still reading from the Tech2. I think he disconected something off the motor as well while this was done. This brought the idle back up to specs.

All I can think of that he might have adjusted is the accelerator cable, as that's pretty much the only adjustable part on the TB?

The IAC controls the idle by letting more/less air in to keep the idle steady - but it's just a solenoid, there's no manual adjustment on it. It's not like a carby engine with an idle screw. Unless he somehow tweaked it with the Tech2 I don't know what else he could have done?

bahaha thats an old pic of my engine bay, and yes that sticker does say idle speed

Yup, not having an Ecotec anymore I had to pinch someone elses, hope you don't mind

 

[cxcxcxvcvcvc]

I really dont think it has much to do with weight difference between VN - VT.....
.

wasn't there about 200kg in difference between the VS-VT models?? if that's the case then i can see where the loss of acceleration/power comes into play!

 

[ruggj]

wasn't there about 200kg in difference between the VS-VT models?? if that's the case then i can see where the loss of acceleration/power comes into play!

yeah i think it was 200kg, i think VT and VXs are in between 1500 and 1550. i know my vx is 1550

 

[lordmuz]

This sounds a lot like my VT - she also struggles off the mark. Sometimes, it feels like it's taking off in second gear. When it's driving at speed (80kmh or so), it behaves fine and kicks back if you give her some throttle. It's just off the mark she's very sluggish. Also, when its in second gear and you floor the throttle, it doesn't kick back to first, it just slowly revs. Does this sound like a faulty gearbox solenoid perhaps?

I have a VS series 2 also, and the VS is quick off the mark. Granted the VS executive is a lot lighter than my VT berlina so the power to weight ratio is totally different - however the VT doesn't feel like it should be this slow. The VS kicks back down to first if you plant your foot, and just screams.

I might check the exhaust for leaks on the VT as a next step... :bang:

 

[lordmuz]

Just an update to my post yesterday - my VT is fine if I manually select the gears (its an auto gearbox), or if I put it in "power" mode.

I have since read that the transmission shift points are controlled entirely by the PCM (which uses the throttle position sensor and the speed sensor to judge what gear to use). Perhaps in "economy" mode, it is just programmed to be a dog.

Thoughts?