Jacob's 99 GTP thread

[Supercharged99]

I don't intend on this turning into any kind of build but figured I'd at least start a thread so that I could keep track of things as the move along. I bought this GTP this weekend and it is to be my daily driver/commuter to and from work which is about 100 miles a day round trip.

First things on the agenda to tackle as soon as possible is oil change, supercharger oil change, possibly wheel hubs (assuming my ABS light isn't due to a wiring issue) and remove crappy window tint so that I can have good window tint applied.

After that will come the less pressing needs such as spark plugs, O2 sensors, new fog light bulbs (one is burned out), new headlights, new taillights, floor mats and a thermostat (temps never get about 175 so I think the current tstat needs replaced).

This car has 200k miles on it but has been well maintained and drives super well. You'd never know it had that kind of mileage on it unless you looked at the odometer. So some of the stuff I'm just doing so that I can start with a clean slate and know exactly when things were done like the spark plugs. The way the car drives I don't think they "need" to be done but I'm probably just going to do it now so that I can say they were last done at 20x,xxx miles. They are cheap enough and easy to do so why not, right?

The biggest flaw on this car is there is rust on the rockers behind the ground effects so I will need to give that attention at some point but will probably hold off until sometime after this winter.

Anyway, I'm sure things will progress as time moves along but that's where things sit for now. I just need her to be a nice, clean daily.

[QUICKSILVER462]

THE Fairfax assembly plant that built Grand Prixs is not to far from there.

[GTP Mark]

Along with what you are already doing, I would say do new transmission fluid and filter at some point too. I usually use Mobil 1 or Amsoil. Some simple regular maintenance and that car will go a long way!

[Supercharged99]

Along with what you are already doing, I would say do new transmission fluid and filter at some point too. I usually use Mobil 1 or Amsoil. Some simple regular maintenance and that car will go a long way!

Great idea! Thanks, Mark. She shifts so smooth now I hadn’t even thought about it but that’s a good point

[Supercharged99]

Today I ordered supercharger oil and found a good deal on a couple timken hubs for the front.

Contemplating doing struts and brakes at the same time I do the front hubs. Haven’t decided if I want to spend the money right now or not.

[Supercharged99]

Acquired the 3 volume set of service manuals for my Grand Prix over the weekend. Cannot tell you how happy I am to have the official service manuals as opposed to a Chilton or Hayne's manual

[Supercharged99]

Got a delivery today and ready for work on Saturday morning

[GTP Mark]

Where did you find those service manuals?

[Supercharged99]

A guy on a truck forum I’m active on had them laying around and offered them to me

[GTP Mark]

That's a pretty good deal. Good call on changing the SC oil. It's going to smell real bad, but worth doing.

[Supercharged99]

Yeah, I’m looking forward to Saturday so I can get that knocked out. My wheel bearings also showed up earlier this week so I’m doing that soon, too. After that will be brakes and struts all on all four corners.

[Supercharged99]

Got spark plugs and supercharger oil change knocked out this morning. Definitely glad that I did this because what I pulled out of the supercharger had a brown color to it so it was definitely time to change it and the spark plugs appeared to have a lot of miles on them.

[Supercharged99]

Well, I did hubs and brakes on the front over the weekend and I believe I found out the root cause for my ABS and traction control light being on. Some previous owner thought it was pretty nice to hack the harness and jump the wire rather than using the plug into that hub. So I have new hubs on both sides and I'm going to order a new harness today to get it fixed up properly. I just don't know why someone would do this rather than just doing it correctly.

Below is a pic for your viewing pleasure.

[wowitsfast]

I can't tell if the black wire it cut or if it continues covered by shadow. If it's cut it will be more involved then ordering a new harness I think.

People do some messed up short cuts to these cars. I've been chasing wiring issues in my car since I bought it 6 years ago.

What I've found is where the hack is has been due to another issue. Selected to be fixed/bypassed at the easiest location to get to.

Sent from my SM-N920V using Tapatalk

[Supercharged99]

I can't tell if the black wire it cut or if it continues covered by shadow. If it's cut it will be more involved then ordering a new harness I think.

People do some messed up short cuts to these cars. I've been chasing wiring issues in my car since I bought it 6 years ago.

What I've found is where the hack is has been due to another issue. Selected to be fixed/bypassed at the easiest location to get to.

Sent from my SM-N920V using Tapatalk

It's definitely cut. So I'm going to replace the harness so that nothing is cut or hacked and go from there. No idea why they'd to that just to patch into the wire on the hub side of thing rather than just using the plug unless a wire went bad and that was cheaper than replacing the old, worn out hub and didn't want to spend the money. Either way, we'll find out here pretty soon LOL

[Supercharged99]

Well, the bearings I'd replaced just a couple months ago already went bad so I replaced them again last night. The bearing I'd bought a couple months ago were off eBay and the seller claimed they were Timkens but when they arrived I'd had my doubts because they weren't in a timken box and they didn't have the "feel" of a timken. This time I ordered from Rock Auto so I know for a fact they are Timken and should last this time around. While at it I also replaced the ABS harness on the driver side wheel so I no longer have the ABS light on on my dash and my TCS system actually works again I also replace the Supercharger Bypass Solenoid to take care of one of the codes that is popping on my dash. This weekend will be replacing the upstream O2 sensor to take care of the other code that is popping and I'll also replace my rear brakes. Next month should come shocks on all 4 corners.

[Supercharged99]

Just to catch everyone up on this since I bought it back in December. Done nothing cool with it other than maintenance and getting that up to snuff. While this car seems to have been taken care of overall there are some things they really neglected.

done since purchase...
—brakes all four corners
—supercharger oil changed
—abs harness replaced on front driver (no more abs or tcs lights)
—spark plugs
—pre-cat O2 sensor
—swapped fogs to LED bulbs
—a few oil changes
—new battery
—front passenger door weatherstripping
—front wheel bearings (twice)

near future...
—front shocks
—supercharger coupler
—headlight housings
—rear door lock actuator
—supercharger serpentine belt. Might do the other belt at the same time but who knows

I’ve got a couple oil leaks that I need to track down too but that’ll be some time later this summer, probably. Not horrible at this point but would be something to tackle when all other things are handled and I’m looking for something to do lol

[SgtMarshal]

even though you don't plan on modding it, a tune could really change the behavior of the car and make it more exciting to drive. and by tune I mean to change the operating parameters of the car's computer

[Supercharged99]

even though you don't plan on modding it, a tune could really change the behavior of the car and make it more exciting to drive. and by tune I mean to change the operating parameters of the car's computer

Yeah, I know what you mean by tune who’s a good person/company to go for a good tune on these cars?

[SgtMarshal]

are you on facebook? look up James Brewer