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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Just Installed Headers, now problems?

  • Thread starter Thread starter bryan0
  • Start date Start date Jun 13, 2007

bryan0

New Member
Jun 9, 2005
175
0
0
Bethel, CT
Jun 13, 2007
#1
  • Jun 13, 2007
  • #1
I just finished installing my mac l/t's and o/r prochamber, to compliment my existing mac catback. I started it up last night. I know I'm supposed to have it retuned with the addition of these parts, but I took it for a very easy 1 mile drive just to hear it.
I was very disappointed, I had a sort of raspy, almost hollow tone. The car also ran pretty... not good. It studdered all over. I'm scared ****less that I have an exhaust leak, as that would requre the removal and re-installation of virtually everything I just did to install the headers.
I got new FRPP gaskets and threw a thin bead of red RTV sealant on the block and headers. The only thing I can think of is that I didn't tighten the egr fitting really tight because there was no room for a wrench. The O2 sensors are hooked up for sure. I know my spark plugs were starting to go the week before I began the installation, I guess that could be my problem, but it seems pretty bad.
I'll be getting my tune hopefully tomorrow and loading that in, is it possible that the reason it's running so bad is because of the lack of tune? Anyone have any insight?

Thanks.
 

Skud

Member
Sep 10, 2003
493
0
17
Saskatchewan
Jun 13, 2007
#2
  • Jun 13, 2007
  • #2
I just installed my MAC headers and the car ran pretty well without getting a tune. I eventually got it tuned though..

I also had the same problem with the EGR fitting. I couldn't get it very tight, but it doesn't sound like I have a leak so I think it's OK for now.

I would wait and see if you end up with a CEL. If you have a leak, it may be throwing off your O2 sensor readings and making it run poorly. Eventually, you should get a CEL.

Did you use the stock studs and nuts?

Riley
 

bryan0

New Member
Jun 9, 2005
175
0
0
Bethel, CT
Jun 13, 2007
#3
  • Jun 13, 2007
  • #3
Yea, I actually went to Ford and dropped $50 on new studs with locking nuts, since the ones that were in there were all rusted.

I just started it up again and the driver's side of the engine bay feels warmer than the passenger's, it could just be my imagination, I don't know. Are there any tell-tale signs I should be aware of? The spark plugs look okay.
Thanks for the reply
 
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