broke exhaust manifold stud and car runs bad?

[Joey7508]

Helped a buddy put on an x pipe on his 03 gt today. All went well except for the passenger side. Where we broke a stud off. I tried to get the broken portion out. It wouldn't budge. I welded a nut to it , heated it up, but after much effort the nut just twisted off with the weld. So I welded a threaded section of bolt to what was left. Put the new catless x pipe on, installed BBK Mil eliminators, and all was well for an hour or so. Now the car is idleing rough and you can hear the exhaust leak at some point. I think it maybe the stud that was rewelded did not hold.

SO my question is would a exhaust leak make the car run like crap. ANd how bad would the leak have to be? If I want to get the stud all the way out I am sure I will need to pull the stock manifold out. Any tips or tricks to getting it off the car. I have alot of hours on my 5.0, but new to the 4.6.

 

[COramprat]

You practically have to pull the engine to get the manifold off but if you have a lift or can get the car high enough you can pull the k-member to get to it.

It would have to be one hell of a leak for it to run badly but it sounds like you didn't get it to seal with the welded thread. You might try some high temp RTV to see if you can get a good seal.

 

[stal94gt]

it is not that hard to get out the stock headers but when i installed my x pipe i broke a stud off to. i got a angle drill and drilled it out. then i just ran a through bolt. and yes your car will run bad if the leak is bad enough

 

[MyStangGT]

The reason it's running bad is because it is sucking air in the leak between pulses. The front 02 sensor senses it as a lean condition and the ECM trys to correct a condition that is not present. It's probably creating a rich fuel mixture on that bank.

 

[blkhorse]

^ yeah,what he said

 

[fast97gt]

The reason it's running bad is because it is sucking air in the leak between pulses. The front 02 sensor senses it as a lean condition and the ECM trys to correct a condition that is not present. It's probably creating a rich fuel mixture on that bank.

 

[9646gt]

Maybe take it somewhere and see if they can get the stud out?

 

[Joey7508]

I am with you guys. I was trying to help my buddy out, but it didn' work so well. He left and worked on it at his house and it turns out it was leaking bad from the drivers side where it meets the manifold. Not on the passenger side where we broke the stud. He worked on it and wound up making things worse. He stripped a stud on the driverside manifold trying to run it down tight. Don't ask me I was not there that time?!? It was a summit x pipe he bought was not the best of quality, but it was a true x and it was cheap. So on the note of you get what you pay for, a cheap pipe and free help. He has decided to get full length headers and another x pipe to match and have them installed at REAL shop. He did price it for the labor at Murillos in SanAntonio it will be $750.00 to put them on. Maybe once he has a few days to think about it he will decide to drill out the broke, stripped studs and run a bolt and nut on them.
And I too made the suggestion of just taking it some where like an exhaust shop to try and get out the broken one the day we did it but now..........

 

[Brute03]

alot of people get leaks on that driver side manifold because the studs have a shoulder, so no matter how much you tighten it, some pipes will always leak there. i had to replace the studs with a kit from NAPA

 

[georgio440]

alot of people get leaks on that driver side manifold because the studs have a shoulder, so no matter how much you tighten it, some pipes will always leak there. i had to replace the studs with a kit from NAPA

How do you pop out the old stud? I stripped one of them on my driver's side as well, but the stud looks like it's on there pretty good. How do you replace it?

 

[Joey7508]

On the stripped one I thought if it s not stripped all the way you can double nut it to back it off.Or you could weld the nut to the stud to back it out. Try not to break it off or you'll be having my original problem. Thanks for the info on the shouldered studs didn't know or check that.

 

[Brute03]

yea, they were a bish to get out. i locked the two nuts on the stud and muscled it off...... make sure you get the nuts as close to the base of the stud as possible, or you'll break it for sure