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Discussion Starter #1
Hello there new GTO owner here, very happy with the vehicle, but there are a few unknown variables about it.
Found unknown chip in glove compartment (attached) no power to it, not sure if part of previously installed nitrous system or seperate.
Was told alot of money in mods installed on vehicle, any tips on what to look for to verify?
Speedometer is off in the range of 2 to 5 mph, not sure if gears were changed, any tips on a remedy?
When at highway speeds transmission seems to go back to third at times, or out of overdrive, then back after a short period, also first through third gear seems to run at higher rpm, car really gets loud an acceleration from a stop, wondering if seperate issue or if the tune is off.
Had those two cables from the battery, not sure if one missing fuse was for nitrous system or the before mentioned chip.
Thanks in advance on any insights that can be given.
 

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That TPP-00007 is a nitrous window switch and those headers look like Kooks Headers. Also clearly has a Fast intake, that's all i see looks to even had a stock air box.

Sounds like a trans tuning issue, hopefully thats it. may be set up with a very aggressive tune. hopefully wasnt beat up too bad

good luck with it
 

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Discussion Starter #5
Ok, thanks, now I know I can just remove that switch.
Yeah I'm hoping tuning issue also, cosmetically the car looks great, seems to run fine, acceleration seems good through the first three gears if more then approximately 25% throttle is applied.
The dealership says the guy put $25,000 into the vehicle and had to trade it in before he could beat it up properly, but yeah I know, it is a dealership, so who knows for sure, there were no pings and it still was putting me back in the seat, so i decided to take a gamble on it.
 

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The dealership says the guy put $25,000 into the vehicle and had to trade it in before he could beat it up properly
Yeah.

Hope the trans is only a tuning issue. If not, take it back to that phenomenal dealership for more advice.
 

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Ok, thanks, now I know I can just remove that switch.
Yeah I'm hoping tuning issue also, cosmetically the car looks great, seems to run fine, acceleration seems good through the first three gears if more then approximately 25% throttle is applied.
The dealership says the guy put $25,000 into the vehicle and had to trade it in before he could beat it up properly, but yeah I know, it is a dealership, so who knows for sure, there were no pings and it still was putting me back in the seat, so i decided to take a gamble on it.
Buying other people's project cars = buying undisclosed problems with some nice parts.

Seeming good is an assumption. :nonono:
You don't know the history, people don't spend $25k+ then trade their project car into a dealer if nothing is wrong with it.
For all you know, the previous owner could of had an issue and the GTO kept tearing up transmissions, so he slapped a stock 4l60e in there and traded it in to get rid of the headache.

He traded it in before he could beat it up properly.
You lying to us, or to yourself? If that is the real statement from the dealer, there isn't a chance in hell you believed it.

Vid filmed on a potato from 2010.
Didn't take $25k of mods for me to beat mine up back then.

All the issues I've been through with my GTO has made me a bit cynical. Maybe you got lucky. :thumbs:
 

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Discussion Starter #10
Not lying to myself at all, already knew it was a gamble going in, said it was a dealership so who knows, but I can see how that could sound naive...

Either way here's to hoping Hubba Bubba isnt holding any of the systems together.
 

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I hope it’s just a tune for you. I bought my car last September with 64000 miles knowing it needed a driveshaft. Driveshaft, cooling system and transmission rebuild within less than a 1000 miles after I bought the car, which includes the 500 mile drive home.

I hope things workout much better for you.
 

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doesn't sound like a trans issue at all, sounds like it has a decent sized stall in it. A bigger/looser converter is going to take some RPM's to get moving and accelerating, I'm at 3500-4500 in mine accelerating depending how much throttle is applied.

As far as the downshifting on the highway, it is likely the torque converter unlocking. That is a pretty simple fix in the tune, the lockup just needs to be adjusted.

All of these things point to/go hand in hand and point to a large torque converter. Most aftermarket torque converters are set to lock up 50-55 and should should really feel it when it does lock up.

The speedo being 2-5mph off, what is the tire size on the car?

Pop off the fuel rail covers and take a pic of what's under there too.

Where are you located?
 

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Discussion Starter #13
Everything you said about a larger converter sounds spot on, and thanks for asking me to take those covers off, now I know where the smoke was coming from when I was at a drive thru yesterday, seems the headers burned off some rubber on a ignition wire sleeve that came in contact with the header.

Tire size is 18, seems stock is 17?

My location is Ridgecrest, CA.
 

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05 and 06 GTO's came standard with 17" wheels. 18" wheels were an option.
 

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You can tell if the car was ordered with the 18's by looking at the tire/wheel tag inside the drivers door. Whichever size it calls out is what the car was ordered with.
 

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Everything you said about a larger converter sounds spot on, and thanks for asking me to take those covers off, now I know where the smoke was coming from when I was at a drive thru yesterday, seems the headers burned off some rubber on a ignition wire sleeve that came in contact with the header.

Tire size is 18, seems stock is 17?

My location is Ridgecrest, CA.
Throw some plug wire sleeves on em, protect me from getting burned.

what is the tire size, ie 275/40/18 etc. If you were local in MD I would have been happy to take a look at it and the trans for you. If it has a big converter then a trans cooler would be a good idea if it doesn't already have one.
 

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Discussion Starter #19
235/40/R40

The ignitor had a pretty thick T shaped boot on it, looks like a L now, rotated it a little, has more clearance now.

Thanks for the offer, if I was in Virginia Beach still would have accepted.
 
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