Pontiac GTO Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
307 Posts
Discussion Starter #1
I don't think my '04 M6 is giving me all the power it should. It seems to not have enough low-end torque, almost like the T/C is still on even after switching it off.

Here's what I did to test:

Fully warmed up the engine. 2nd gear, slow roll at around 10 MPH with T/C off. Nailed the throttle to the floor, and the tires didn't break loose at all. Not even a chirp, there was a bit of hesitation before the car started moving, and I really didn't feel good acceleration until about 3000 RPM.

After I hit about 55 MPH, I let off the throttle and let the car coast back down to around 10 MPH, then repeated the process several times (about 15-20 of them within 20 to 30 minutes).

Although the last few launches felt more powerful than the first few, shouldn't the GTO be able to break the tires loose when I nail it like this?

Could the computer be mis-programmed?
Is the engine still too new and tight (685 miles) to be making its full power?
 

·
Registered
Joined
·
153 Posts
Mine runs pretty much the same (no wheelspin on 10mph 2nd gear rolling mash.)
There are days when hard first gear acceleration breaks loose everywhere and others where the car just really hooks up. I've got over 10k miles on her and it still a blast to drive, if only I could find the variable that keeps it toned down every once in a while :D . I has nothing to do with T/C because I generally leave it on.
I'm running 89 octane right now because the station was out of high test and I had to be somewhere. Come to think of it, it always runs strongest on Sheetz premium gas. :D
 

·
Registered
Joined
·
20 Posts
Low on power

I posted a similar question awhile back because my 2004 GTO M6 seems to lack the power that I think it should have. My car has approx 2675 miles on it and when I hit the hammer even with the T/C turned off the car just doesnt do much. Maybe Im expecting too much for a heavy car and since i owned a AMG mercedes in the past and other high performance cars. Im thinking of trading it in for a 2005 GTO and maybe the extra 50 hp will be more noticeable.

My fuel economy also isnt close to the advertised figures but over all I love the car .I do wish that the drivers/passengers windows and outside mirrors would defrost on rainy or poor weather days.
Phillip
Calif
 

·
Registered
Joined
·
96 Posts
Thats strange. Sometimes I chirp the tires at 60mph on my 2nd-3rd shift. I hear that the ECU adapts itself to your driving style. When you baby it, it configures the engine to be conservative with power. And it doesn't open up until you hotrod it for a little while. I've heard other GTO owners complain of this also. Me, I have the opposite problem. I can't hook up. A few weeks ago, I almost lost to a Dodge Dakota. Guy said it had a 318 and a POSI with fat tires. He took me off the line just because I couldn't hook up, but I caught up with and pull ahead of him.
 

·
Registered
Joined
·
307 Posts
Discussion Starter #5
bsmcall said:
Mine runs pretty much the same (no wheelspin on 10mph 2nd gear rolling mash.)
There are days when hard first gear acceleration breaks loose everywhere and others where the car just really hooks up. I've got over 10k miles on her and it still a blast to drive, if only I could find the variable that keeps it toned down every once in a while . I has nothing to do with T/C because I generally leave it on.
I'm running 89 octane right now because the station was out of high test and I had to be somewhere. Come to think of it, it always runs strongest on Sheetz premium gas.
I have been running Sunoco Ultra 94 and of course the T/C was turned off when I did this. Today I tried the same thing but in 1st gear instead, starting with clutch fully engaged and rolling around 7 MPH (just under 1000 RPM in 1st), stomp the throttle and a bit of a hesitation, no wheelspin, then after about a second the car wants to move, and over 3000 it really MOVES (like full throttle should feel).

IH2ton6cyl said:
Maybe Im expecting too much for a heavy car and since i owned a AMG mercedes in the past and other high performance cars. Im thinking of trading it in for a 2005 GTO and maybe the extra 50 hp will be more noticeable.
My other car is too embarrassing to list here, suffice it to say it's a severely underpowered egg-shaped economy car. I've never owned a car with more than 150 HP before (and the aforementioned egg-shaped car has less than half of that). I tried seeing what kind of deal I could get on an '05, but no dice. Early termination of a lease is not possible without taking a serious (more than double) payment increase.

stucker said:
Thats strange. Sometimes I chirp the tires at 60mph on my 2nd-3rd shift. I hear that the ECU adapts itself to your driving style. When you baby it, it configures the engine to be conservative with power. And it doesn't open up until you hotrod it for a little while. I've heard other GTO owners complain of this also. Me, I have the opposite problem. I can't hook up.
I followed the break-in procedure in the owner's manual, which is pretty conservative driving. Maybe I just need to pull a fuse or the battery cable (?) to reset the ECU? I eventually plan on getting some "reversible" modifications such as ECU programmer and K&N intake. Will the K&N or other similar CAI hurt the low-end?

There are a few other issues such as spongy/low brake pedal on initial application (pumping helps) and a slight knocking/vibration noise at idle when warm (possible exhaust leak?) that I'm taking the car to the dealer for, and also to change the oil to Mobil1 tomorrow.

--
Thanks to all for your help and I'll let everyone know what happens @ the dealer.
 

·
Registered
Joined
·
139 Posts
Big Nick--I put a K&N CAI on my car which is the same as yours and I don't have any low end problems. There are a lot of debates about CAI and I believe that mine works better over the stock. There was a write-up about this in Pontiac magazine a few months ago and they found that a CAI helped at the track and the dyno. I don't have to many problems breaking my tires loose almost any time that I want. However, I do know that there are different types of pavement (compounds, dirt, grease, heat, cold, angle, etc.) that come into play so you will have different experiences on different days in different areas. There are even debates on whether you should baby your car at first or break her in a little harder. I chose to break mine in a little harder but in moderation and I haven't had any problems yet and she moves quite nicely.
 

·
Registered
Joined
·
139 Posts
I owned a 71 Chevelle & currently own a 70 GTO & of couse the 04. The older muscle cars don't have computers but if you drive them like a grandma most of the time then its not going to respond the way that you would like when you need the power because you start getting carbon built-up inside of the motor. These car weren't designed to drive slow they were designed for power and speed. I'm not saying that you need to be driving above the speed limits but getting to those speeds very quickly is more what I'm talking about.
 

·
Registered
Joined
·
307 Posts
Discussion Starter #8
Results of dealer visit

Got my car back this afternoon from the dealer.

The engine diagnostic came back normal, that they could not duplicate the problem, said I was "possibly feeling TCS engagment". I had the T/C off.

The light rattling noise and soft brake pedal were also not considered to be defects, but normal characteristics of the car. Maybe some stainless steel brake lines will help the pedal feel?

I did get the oil changed with Mobil 1 and a magnetic drain plug installed (they had to order a "Mobil 1 Only" oil cap).

Total was just under $65. 7 quarts of oil at $5.50 a quart came to $38.50, more than 1/2 of the total (I guess they don't charge in 1/2-quart levels for a 6.5 quart fill-up).

Nothing on the paperwork states they re-flashed or reset the computer. Would I have any way of knowing if this was done or not?
 
1 - 8 of 8 Posts
Top