problem MAC H pipe install

Hammer1999Gt

Member
Mar 26, 2004
169
1
16
Toledo, OH
Well I tried to install my H yesterday and it did not go so well. I didn't have any trouble getting the factory H out. For some reason one of the passeger side manafold nuts was missing so I only had to break one lose on that side. The problem began when I tired to install my 2 peice O/R Mac H. It seemed to bolt up ok but all 4 of the O2 sensor wires were too short. So I got pissed and just reinstalled the factory H but I couldn't get the front passenger side O2 harness pluged in. I can't get it with only one hand that I can fit up there. SO right now my car has a CEL on because teh sensor is unpluged and I have a H pipe sitting on the floor that doesn't seem to be for my car. So my question now is what is wrong with my H pipe is it for a 96-98? I don't know what the difference between a 99-04 and 96-98 is? I have a 99 by the way. The holes for the sensors are definelty not in the same locations as the factory pipe? Has any one with the old 2 peice model had this problem. Please help; do I need to raise hell with the guy who sold me this thing on ebay?
 
I'd double check it's for the right year. IIRC, the '04's are the only year which need the extensions, but I haven't even thought about them in a while. If your FRONT o2 sensor isn't plugged in, then expect some serious rich/lean conditions. It's tough to get it plugged back in.. there's a little plastic mounting plug that holds the upper part of the sensor connector on, I just yanked real hard til mine came off, but I wouldn't advise it since I don't know if 99's are the same as my '04 is.
 
Yeah, getting those front sensors plugged back in were a pain when I put my H pipe on. I actually had someone else reach in from the engine bay to just hold the top half of the plug steady while I plugged the other half in from under the car. That seemed to work pretty well.
 
I had to disconnect the front-driver's side o2 to get it to connect (on my 2004), as the o2 bung is lower on the MAC H than on the stocker (longer reach). It was still tight pulling it down to meet it. I'm waiting for the day it stresses a bit too much. I also didn't use the 2-piece pipe, mine was three. I think the legs are fabbed the same; just the H chamber is pre-fabbed together.
 
So the problem is that MAC made all thier H pipe's with the O2 holes in the wrong spots. One on mine are off. Bham_gt you said you can reach the top half of the plug from the top of the engine bay? I really need to get that pluged back in.
 
Hammer1999Gt said:
So the problem is that MAC made all thier H pipe's with the O2 holes in the wrong spots. All 4 on mine are off. None of the O2s are long enough to plug in. They are all too short. Bham_gt you said you can reach the top half of the plug from the top of the engine bay? I really need to get that pluged back in.

If you have the hood up, it will let light in for you to see better. Small/skinny hands help--or yes, you can have a buddy push the plug/harness down to you to get the o2 connected.
 
Hammer1999Gt said:
Thanks I will have to try that. I already have pretty small hands and arms. I can get my hand up there I just can't plug it in because the harness moves when i try to put it together.

Just be patient and make sure to have a buddy around when you get the install done. You don't want to be the only one standing there, grinning like a dumb___ when you hear the sound! :D
 
Yeah, it must be the wrong pipe. All of my sensors reached just fine. And, yes, you can get to the top of the plug from the engine bay. That really helped out when I was trying to plug mine back up. And small hands definitely do help when you're trying to get that done.