I have a 2003 fx4 auto, no cat 4" exhaust. I was having problems with it studdering when it would shift into overdrive, I would have to hit the tow button to keep it from studdering. Now my new problem, I have just finished some upgrades and the studdering is gone. I had a bad #6 injector that was causing the studder, so I replace the injector, also I replaced the oil cooler and blocked off the egr cooler and updated the icp pigtail,re-routed the cvc replaced all of the filters (motocraft) except a puralator air filter also changed the oil (hot shot added also). My truck will crank and run and shift fine, until you accelerate or hit a hill it just looses power and I cant hear the turbo whistle like I used to its there just not like it used to be. I have done the turbo relearn and it still runs the same, the sound of the truck is different, it makes a low toned growl on occasion, kinda like a broken exhaust pipe, It will make this sound for about 30 sec. and then it makes its normal sound for about 30 sec it goes back and fourth like this while idleing, also I can hear it his intermitently when I stand at the rear of the truck, I hear the growl mostly on the driver side. Ive checked all of the pipes to the turbo, all four are on as tight as I can get them and they fit snug against the turbo, the cac boots look ok, Ive tightend the air intake bands, and made sure the hose from the map is connected. I have oil in the up pipe from the cooler to the intake elbow and I noticed that I am missing a bolt on the exhaust manifold(Driver side). I am at a loss as what to do now, How can I check for a cracked Y-pipe? I guess its off for a good screwing from ford if non of you guys have any advise.

 

OK, I took the truck to the dealer to have it diagnosed. They are saying it is an exhaust leak causing the turbo not to spool. But I spoke with the mechanic and he is unsure of where the leak is????????????? but he says thats whats causing the llow boost, I think they took my 65 bucks and are laughing. I cannot find a leak, I put my hand at all of the joints on the y-pipe and I cant feel anything. Does anyone have any suggestions on how to find a leak. Im not real confident with my dealer and hes the only dealer within 60 miles, so Ive got to fix it myself, (and no I dont have any warranty left).

 

Sounds like the vanes in your turbo may be cycling to full open causing the change in your exhaust note/tone that you cited. If it's doing this, it should show up on a diagnostic check. Did the tech perform a diagnostic?

 

I dont know if they did or not, I ask them to diagnose the problem that I was having. I assumed they would have put it on the scanner first but who know. I did finally get a check engine light today 2263 but that could have happend today after I had unbolted all of the bolts on the turbo mount and noticed I was pouring oil, I had accidentally pulled out the drain tube from under the turbo, man I must have lost two or 3 qts of oil. I cleared it and tried set it off again but I havnt been able to do so. I think I am going to take the turbo off and clean it, It took me about a 2 weeks to get my truck going while I was waiting on parts to arrive, the turbo set on my work bench the whole time, maybe the vanes are stuck, can I remove the vgt and clean it? do you think will it make a difference? tomorrow Im going to weld the egr shut and re torque the intake manifold bolts. and if that dont work Im taking the turbo apart, wish me luck.

 

One other thing that just hit me. When I replaced my turbo, the vgt connector broke into several pieces because it was brittle from heat. I didnt know wich wire went where, so I just hooked them up, I know I got them on the wrong side because I got a new plug from a junk yard and the wires were on the opposite post, could I have shorted the vgt out? and how do I check it? can I use a multimeter? what values should I look for?

 

I found the problem, After much digging it ended up being loose intake manifold bolts on the passenger side. How could the dealer miss this and tell me it was the exhuast leak near the back of the turbo. Anyway I was able to find the leak with a can of starting fluid. I had to retighten the bolts about 5 times to get them to seat. Anyway thanks for the help. Now Im off to buy a coolant filter kit.

 

Good on ya Hacksaw!