engine swap runs like crap,... suggestions?

[dream07]

I pulled the 5.4 from my 2007 and stuck in a 2007 4.6, 5 speed and pcm (all from different sources). No mods, all 100% stock parts. I had the keys entered into PATS and it started right up. I drove around the block and it had a "soft" gas pedal response pulling out and stumbles, then half-throttle or more it ran great. I drove 3 miles and came home.

The next time I took it out, it did the same thing. Tough to pull out when the throttle gets all wacky. Then, the check engine light came on, so I went home to read the codes. They were passenger o2 #1 stuck rich, driver's o2 #1 stuck lean and nothing else. How the hell can one bank be lean and the other bank rich??? I installed new Ford o2 sensors (all 4) during the swap.

My friend brought over his x4 tuner and we looked at fuel pressure, mass air meter numbers and a few other parameters, but nothing seemed out of line. It showed the VIN# on the tuner, so pcm should not have a custom tune in it, since it didn't show up, right?

Now I am confused and frustrated. Anybody want to make suggestions on where to go from here?

 

[truckman7]

Cel light on? Any codes or the wrench light on?


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[redfirepearlgt]

Easy to get the O2 sensor cables crossed. Have you checked that? If backwards they can create some really weird scenarios like you are seeing. Double check the wiring layout within the 2005 Ford tech manual in the engine section if I recall right. if crossed this causes the PCM to add fuel or take away fuel from the wrong bank. The end result is that both sides are running away due to improper feedback caused by cables being crossed.

 

[dream07]

Hmmmm...I've heard of that, but I didn't think to double-check that. I just laid out the engine harness and assumed the logical left/right location. Maybe I need to jack it up and verify that. Thanks!

 

[TexasBlownV8]

While you're under there, look the harness over, make sure it didn't get caught/pinched somewhere. But the wrong o2 sensor connections would be a problem

 

[dream07]

Well, I finally got a chance to take off the H-pipe and look at the wiring layout and compare it to a Ford diagram.

Yep, Redfirepearlgt nailed it. I had the passenger O2 hooked up to the driver's side and vice versa. Unreal. I can't believe they fit both ways and have no way to tell which is which.

I guess if I just bought a GT I wouldn't have these problems.

Anyway, it runs great now (well, for what it is). I even put in the 93 octane tune and picked up great seat of the pants feel. The swap is finally done, now to drive it to set the monitors and take it for A/C charge and safety inspection.

 

[redfirepearlgt]

AWESOME MAN. Glad you got it ironed out. Too many times in my line of work I find half of my problem on an install or machine move is crossed wiring somewhere, or a wiring harness that got tucked behind something that didn't get plugged in.

Now all you have to do is the punch list items and take it to the track and bust some numbers off.