1999 VT Series II Holden Commodore SS 

5.7 litre alloy GEN III LS-1 V8,  fuel injection, 4 speed auto

Purchased new in June 99 from R & B Smith Holden.

Engine Specs : 220Kw @ 5000RPM, 446Nm @ 4400RPM

• 17x8" wheels with Bridgestone 235/45R17 
• Limited slip diff, ABS Brakes, Traction control, IRS
• Dual Airbags, Cruise control, Tinted windows
• Berlina stereo head unit with 10 CD stacker

General notes :

• Fuel economy : around 17L/100Km for my typical home<->work route which involves a mix of 100/80/60Km/hr driving. Straight highway driving drops the consumption to around 10 or 11L/100Km
• Traction control is a must-have on this car when the road is wet. I have tried turning it off a few times, but it is almost impossible to corner or accelerate safely without the traction control enabled. When the TC gets tripped, the accelerator pedal pushes back up quite sharply, as the car backs off the power. Also the car uses the brakes to stop a wheel from spinning if need be. You can be parked on gravel and then put your foot down hard and the car will crawl away without any wheelspin.
• The auto transmission would have to be the weakest part of the car. It is not very clever and regularly will downshift at an inappropriate time. My feeling is that the engine has enough power that the transmission shouldn't need to downshift too eagerly. I think that it would be a good feature if Holden  spent a few more bucks putting more intelligence into the transmission - from memory the Falcon and even Magna/Camry have adaptive shift patterns that take note of how aggressively the car is being driven - and adjust the shift points appropriately. (As a side note, a Holden workshop foreman recently emailed me to let me know that Commodores from VR onwards adaptive learning for "both fuel trim and Trans shifting/ line pressure". I thought that was interesting as I hadn't ever noticed the transmission shifting differently after some hard driving... I will have to pay closer attention to see if this learning is noticeable.
  SEE SNIPPETS OF CONVERSATION WITH FORMAN BELOW FOR MORE INFO)
• You sometimes get a nasty clunk from the diff when you go make a left/right hand turn in a suburban intersection. It seems to be that you get the clunk because you are coasting to the corner and then as you go around you apply accelerator and as the drive returns to the diff it clunks as it changes from freewheeling to driving.
• In general the car has plenty of power. In particular if you floor the accelerator at 100Km/hr, you are nearly blasted out the car with acceleration. You really have to hang on tight to the steering wheel if you  are trying to pass a car on an undivided road. However around town, sometimes the car doesn't feel super strong. You really have to get 2500 to 3000rpm up before the power is unleashed. If you want the car to be extra zippy around town, you have to put the auto into "3" rather than "D".  

Problems so far (in the 1st 10,000 Km's) :

• Power aerial doesn't extend to full height (later on I found this was due to the arial being bent)
• Trim on interior of drivers side B-pillar doesn't fit properly (fixed by holden at the 10K service)
• Trim to the left of the steering wheel on the lower dash doesnt fit properly (fixed by holden at the 10K service)
• Rubber seal around base of drivers door is misshapen and is hanging down so it is visible from outside the car (fixed by holden at the 10K service)
• On 3 occasions, engine has lost most of its power. Engine/transmission warning light comes on and car looses most of its acceleration. You can still get up to speeds like 100Km/h but it takes much longer than normal. Because the car is auto, this lack of power also causes the transmission not to want to shift gears at the appropriate times. Once I took this into the dealer while it was happening, in the hope that they could plug in their diagnostics computer to find the fault. After a lot of waiting around, the guy came back and said he and another mechanic had driven the car and couldn't find anything wrong with it - he claimed it was "working  good, real good". I thought "Oh well, maybe the fault has gone away again before they started testing". However, when I got back in the car the fault was still there. The staff at the dealership had told me that these engines were still very new to them and they were still learning all the ins and outs. However I was very disappointed to find that they didn't have enough knowledge to notice the engine was developing much less power than normal. Perhaps they thought I had a 6 cylinder engine, not the new 5.7 litre. The guy at the dealership said the diagnostic machine told them my cars computer had logged a transmission fault and also engine knock. I suspect the lack of power is to do with the engine knock - either poor quality fuel or a misbehaving sensor. I think this would explain why there was no power as maybe the computer is severely retarding the ignition?
• Has been recalled twice for faults - once for a transmission computer fault, and once for a steering fault.

INTERESTING SNIPPETS OF A CONVERSATION I HAD WITH A HOLDEN WORKSHOP FOREMAN

[ insert my questions here about auto trans and adaptive learn]

Just to clear up about Adaptive learn, as far as the trans goes the shift points won't alter (Unlike Mitsubishi) as they are programmed to a set map but line pressure is adjusted to give better quality shifts. (It works similar to short term fuel correction and long term fuel trim). The PCM monitors the engine speed and the output shaft speed to determine if the shift is occurring too fast (harsh) or too slow (soft) The PCM adjusts the line pressure to maintain the correct shift feel. So if you drive hard most of the time it will remember the line pressure to use for a good quality shift even under heavy acceleration & also if you drive mildly it will learn what pressure to use.

As far as your Knock Sensor is concerned that was a software problem. Basically the PCM runs self tests on all sensors and circuits to ensure all is correct, if it's not it will log a DTC (Diagnostic trouble code) and in most cases turn the Check Engine Light on (orange engine shaped light on instruments). We can read this information when we plug in our hand held Tech-2. In the case of the Knock Sensor it's job is to detect Detonation (knocking, pinging) in the engine and the PCM reacts by retarding ignition timing slightly, if the Knock Sensor or circuit fails the PCM detects this and because it can't tell if there is detonation it retards the timing more than it would otherwise to prevent engine damage, that is why your car felt so sluggish (sort of a limp home mode if you like).The reason it was a software problem was that the diagnostic software in the PCM was over sensitive and was picking up that the Knock Sensors were at fault when in reality there was nothing wrong with them. The problem is easy fixed as the PCM's can be flash programmed, GM put the new software on CD-ROM and we just download it onto our handheld computers (Tech-2) and then reprogram your PCM with them. Actually there is factory software available in America for huge KW outputs from the GEN-3 but they aren't releasing it for Australia.

Just for your interest you may like to know that a top of the range VT can have up to 6 microprocessors 

1. PCM powertrain control module 
2. BCM body control module 
3. ABS anti-lock brakes 
4. Instruments gauges, trip computer 
5. SRS air-bag 
6. ECC electronic climate control

All of these are connected by the serial data bus and share info from all the different sensors. For example the coolant temp sensor is used by the PCM, ECC & Instruments.

The GEN-3 is a little different in that it uses Class 2 serial data and every thing else on the VT uses UART serial data. Because the GEN-3 and its PCM are all directly imported from America it would too expensive to engineer a new PCM so all Australian GEN-3's have a PIM (powertrain interface module) that acts as a translator between UART and Class 2 so it can still communicate on the bus.

Hoping some of this helps and I haven't waffled on too much. Cheers

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[ insert my questions here about 10K service software update, hm headers, capa airflow meter upgrade ]

Dear Michael, to answer your questions in order

1) As far as reprogramming the PCM's with the latest software we would only do it as a matter of course at say the 10k service if we get time but mostly we only do it if the customer has complained the check engine light has been coming on and the Knock sensor code is logged, or if the vehicle has some driveability problem that can't be sorted out. As far as you are concerned it might be best to ask for it to be done then you know it has been.

2) I don't mind if you use some of this info in your website, just one thing I ask is that you don't mention my name or the dealership I work at. That may sound like a strange request but some people who read it may think I'm expressing views of Holden or my dealership.

3) I honestly couldn't comment on Holden's policy as far as after-market parts and warranty, you are best to speak to your dealer in that regard. Another cop-out I know but I hope you understand my position.

4) Just one thing to watch when increasing the power output of the GEN-3 and that is you find after you have made the mods the car will go really well for a while and then you will find the power seems to drop off, this is due to the PCM trying to correct the Long Term Fuel (LTFT) Trim back to the standard power output. The only way around this as far as I know at the moment is to put a toggle switch between the battery and the PCM on the keep alive power wire, and every time you turn the car off you turn the toggle switch off for at least 10secs and this resets the LTFT correction cells back to 0. I did hear of someone sending an Australian programmed PCM over to America to see if he could re-program the PCM not to correct so much and keep the increased output but I haven't heard back on that one. I'll try and keep you posted.

Car was traded for a VX II Sedan