need help haha running out of ideas , ok when idleing it skips but not like clockwork you can hear one miss then it will be two or one then one it's all over the place when i load it up or rev it up sounds like crap and shakes , um i did have the wrong plugs in so i changed those and the wires are only 3 months old , new o2 sensers , the coil packs are fine , i have this code coming up all the time dont know where the senser is or how to fix it . p1549 intak man comm ctrl cir . oh sorry the truck is a 99 f150 with a 4.6 wiring harness but a 5.4 engine , any info would be nice

 

vacuum leak on the Intake Manifold Temperature Valve Vacuum Actuator Connection??

 

What did you do with the Intake manifold tuning valve? Was it tuned out when the 5.4 was put in? If not did you not leave it connected? Here is where I put mine and left it connected.



Regards

Jean Marc Chartier

 

yep it is connected , do you need to tune it out , i got a tune from VMP and i just told them my up grades and that i did a 4.6 to a 5.4 swap with the 4.6 harness still in use . what could happen if it's not tuned out

 

If it is still plugged in and not tuned out then check for chaffed/cut wires or interference stopping it from turning.

Regards

Jean Marc Chartier

 

could that make the truck miss fire or skip and run like it's on 4 cyclinders. what else could it be if not that ,just put in a new fuel filter and cleaned MAF and still not fixed problem , i had same find problem before and it was plugs and wires but i just put new plugs in nothing and wires are only 3 months old could it be wires too , testing the cam sensor tonight

 

You may have done this already but, when you replaced the plug wires did you check the length of the boot? Sometimes the boot is longer than the plug and a bad connection is a result. I found that out through my own experience. I just cut the boot back and verify the plug makes a good connection then reinstall wires and plug.

 

will it hurt any thing if i just cut off 1/8 inch off all . and keep the info coming haha need to get this truck fix and ill keep on posting progress

 

I haven looked into what powers the IMTV but if it shares a circuit with the coils it injectors I may cause it. I always fix the codes first.

Regards

Jean Marc Chartier

 

so is it the imtv that is throwing that code p1549 , plus were it was sitting on my truck when the shop did the swap for me they just had it wedged between wires and the rocker cover so i dont think that thing could turn now could it be that the intv is bad and i need to get a new one.. oh plus the cam senser is good

 

Did you ever firgure this out? I have the same issue, code 1549 on my 99 f150 with a 4.6 harness on a 5.4 engine. Truck has been runnign fine for years. Just started acting like its missing on cylinders.