A few issues to sort on new car (1999)

optionizerSS · Jul 23, 2023

Went and looked at a 1999 GT convertible today. Step-son put a deposit on it. Has a few issues that need fixed but seem mostly minor. First is it stalls when putting it into gear when it is cold. Checked CEL and got a P0420 and a P0174 code. It has an exhaust with no cats so that explains the P0420. The P0174 could be a few things but guessing it may be related to the stalling?
The other issue is a slight pull to the right that gets worse when applying the brakes. Seller says he just had front pads, rotors, calipers and hoses replaced last week. Gonna check ball joints, tie rod ends and steering rack once he gets it. He is still in court for a homicide case so he probably can't get it until Tuesday or Wednesday at the earliest.
Oh, forgot, ABS light is on too. probably wheel speed sensor but will dig into that later.
Has a few dings, chips and scratches but he got a pretty good deal I think. Car is yellow with black top and black wheels. Has 116,000 miles.

96blak54 · Jul 23, 2023

A yellow convertible! Sweet! Im not a fan of convertibles, but a yellow mustang i am. Good news is, every problem the car has or will ever have is already figured out, so you shouldnt have much worries with the purchase. Congrats with the score!

optionizerSS · Jul 23, 2023

96blak54 said:
A yellow convertible! Sweet! Im not a fan of convertibles, but a yellow mustang i am. Good news is, every problem the car has or will ever have is already figured out, so you shouldnt have much worries with the purchase. Congrats with the score!

Yeah he is excited. He has a side by side and was gonna sell it for a slingshot. I gave him the keys to our '95 GT convertible and he came back and said he wants one...lol.

maillemaker · Jul 24, 2023

Stalling when going into gear could be a vacuum leak.

optionizerSS · Jul 24, 2023

maillemaker said:
Stalling when going into gear could be a vacuum leak.

I was thinking that too since it also has a P0174 code

optionizerSS · Jul 24, 2023

And the IAC looks like it is new too so guessing they tried that too

optionizerSS · Jul 25, 2023

Well he got the car. Definitely has exhaust leaks. Looks to be cast manifolds and sounds like its leaking near the engine. He is looking at installing shorty headers and replace the exhaust (cats have been deleted but he wants to put them back on). Pretty sure the right front wheel bearing is going. It has a slight pull to the right and sounds like it is growling a little. Also has an ABS light on so likely the bearing needs replaced. Also has a P0174 code which I'm thinking may be a vacuum leak but haven't dug into it yet.
Drove it an hour to get home and it seems to run great.

1999 GT 4.6 auto 116,000 miles

ttocs · Jul 26, 2023

abs light on constant can mean it just needs to be filled.

96blak54 · Jul 26, 2023

Take a good picture of the engine. Lets see if we cant do some simple observation diagnosis.

Id be willing to bet the car has a different engine. Most of the early new edge 4.6l liked to spit sparkplugs out and destroy cylinder walls and heads.

If the intake gaskets are not the proper 4.6l gaskets for the ford intake manifold, there will be leak issues. The gasket will appear correct but their thickness is all the difference. At my work, where the manifold was produced, we found that the original/felpro 4.6l intake gaskets where the correct thickness for the allowance of warpage these intakes have when made. Surprisingly even the factory ford 5.4l intake gaskets(appear identical, but not)are not as thick.

optionizerSS · Jul 26, 2023

Hard to say if anything is original on this car. It has Saleen ground effects and bumpers. The fenders have the 35th anniversary badges. We are assuming it is a GT that someone threw Saleen stuff on but not sure. It may have started life as a V6 car for all we know.

maillemaker · Jul 26, 2023

optionizerSS said:
Well he got the car. Definitely has exhaust leaks. Looks to be cast manifolds and sounds like its leaking near the engine. He is looking at installing shorty headers and replace the exhaust (cats have been deleted but he wants to put them back on). Pretty sure the right front wheel bearing is going. It has a slight pull to the right and sounds like it is growling a little. Also has an ABS light on so likely the bearing needs replaced. Also has a P0174 code which I'm thinking may be a vacuum leak but haven't dug into it yet.
Drove it an hour to get home and it seems to run great.

1999 GT 4.6 auto 116,000 miles

If you think it has exhaust leaks because of the smell, it may just be because it has no cats. I bought mine about 4 months ago and it also was cat delete. Car stunk of exhaust. Was nauseating. Especially in a convertible with the top down. But even top-up it stunk. And the garage stunk.

Had cats put back on, no more smell. Car doesn't sound as cool but it's worth it not to have an exhaust headache.

optionizerSS · Jul 26, 2023

no i know the smell is cause of no cats but i can hear exhaust leaks too

joemomma · Jul 26, 2023

The 35th badges were on all '99s is memory serves, even without the 35th anniversary package. My base '99GT had the badges but not the package.

As far as exhaust, it'll still sound good with the cats in place and just some Flows welded in.