[HELP] Car surges after switch of midpipes

Twista

Active Member
May 7, 2004
510
1
29
@ the z00 in chicago
#1
I have stock headers, mac o/r H and mac catback. Already resetted the cpu by unplugging the battery.

So, i switched midpipes many times before and this is 1ST time this has ever happened.

So, i had to swap my mac o/r H pipe out for my mac catted h and everything went as planned expect the gasket wasn't holding like it should. Anyways, the car developed a nasty leak, but i took it for the emission test anyway and passed.


Fast forward to today i went and brought a new gasket from ford and put back on my Mac O/r H. The surging problem is still there

It happens when you take off from a stop. The 1st couple rpms the car is like bogging down and surging and you can hear it and feel it.

Downshifts than accelerating it the car is normal.

The only thing i messed with was the rear o2 sensors.

Does this sound like an exhaust leak somewhere? If so, i cant hear this baby.
What could a exhaust leak damage? The o2 sensors???

Damn it.!

Thanks

edit: while this was happening with the catted midpipe on.. there was no MIL OR CEL ON. NO CODES
 
#2
An exhuast leak before the upstream o2's will cause the puter to think its lean (unmetered air in the system) and there fore it will actually inject more fuel. That could cause a bucking issue down low.

What codes is it throwing now if any?
 
#3
squeak93 said:
An exhuast leak before the upstream o2's will cause the puter to think its lean (unmetered air in the system) and there fore it will actually inject more fuel. That could cause a bucking issue down low.

What codes is it throwing now if any?
Click to expand...

Not sure of the codes, but im sure im throwing the no cat code. So i will take apart the mid again and try re-seating it.

I pray this is the problem.

ty
 
#7
squeak93 said:
Link is blocked.... What does it say?
Click to expand...


..........
 
#8
There could be damage to an 02 sensor or the connecting wire. I'm surprised you are showing no codes. I just installed my first midpipe and I can see where some damage could have been done. Try to pull codes if there's any. Pearl02.
 
#9
I just brought 4 new sensors, but there being shipped. So what would happen if i unplugged the sensors and test it? Or does the car need the sensor for it to operate somewhat properly?
Just wondering if i unplug the 2 front ones would the car drive normal if they are faulty?
 
#10
If you unplug the front sensors you take away the cars ability to "adaptive learn". That means it cannot make on the fly fuel adjustments to get the optimal performance and mileage. The rears will not cause what the link above eludes to. The rear o2's Simply tell the puter if the cats are working or not, w/o cats or mils you will get a rear o2 code..... That will not affect performance whatsoever. With that said, if your fronts are bad if can cause all sorts of crazy stuff to happen. Not likely that both fronts went at the same time unless you caused damage to them when removing and reinstalling.

Never hurts to buy new o2's but I fear this likely won't solve ur issue.
 
#11
I think i got the problem pin pointed, just i cant access the sensor. So i guess driving with the bad exhaust leak on the passenger side somehow sent the soot to my air flilter which is black and gunky nasty. So, with that said.. my MAF has to sooted to hell. I brought some MAF cleaner but i have to buy a t-20 female torx =[
 
#14
Yea no gasket will cause one big leak but how the hell did it dirty up ur air filter? Those two are a long ways apart. Is it an engine bay filter or is in the fenderwell. If your filter is that dirty then your whole engine bay must look like a chimney.....
 
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