Random sputtering and loss of power

[Jbpul25]

I have 2001 ford ranger xlt 4.0, I had the same problem ever since I bought the truck though. It runs great most of the time, starts up nice has good power, but sometimes randomly or if I slow down to quick, the rpm's drop to 500 and when I try to accelerate is starts sputtering almost as if it misfiring and has lack of power. This problem doesn't usually last long maybe 45 seconds tops and then its like a switch was turned and the rpms are back to normal and I have full power. Now I have gone through a few possible possible problems starting with new plugs and wires and coil pack. next I did MAF sensor and that didn't help, then Inspected and carefully cleaned IAC valve of all the carbon build up. Just recently I have had changed PCV valve along with line and elbows that were super corroded and that had made a noticeable idle difference. I still seem to be having that problem though, I should note that sometimes when this happens the smell of the exhaust gets a little funky smelling which makes me thing there might be something wrong with the cat converters , Do I need them ? could I just straight pipe it ?

Any feed back would help, thanks

 

[nitris]

have your ever done a full tune up on this truck? sparks, wires, fuel filter, air filter, MAF sensor cleaning... etc.... or even a really good fuel treatment where you take it to like pepboys for $89 bucks and let them drip the injectors, put treatment in the gas tank and clean the throttle body to really get all the gunk out? this helped my truck.... it smoked really really bad while it was being cleaned but made a world of a difference.

 

[Jbpul25]

yea ive done a couple seafoam treatment which help momentarily but I have done plugs wires, air filter, MAF sensor, pcv valve and elbows, I should try the full fuel cleaning, I pulin a code of an 02 sensor which I have just haven't put in yet but that shouldn't really make it run difference, should it ?

 

[nitris]

yea ive done a couple seafoam treatment which help momentarily but I have done plugs wires, air filter, MAF sensor, pcv valve and elbows, I should try the full fuel cleaning, I pulin a code of an 02 sensor which I have just haven't put in yet but that shouldn't really make it run difference, should it ?

it shouldnt but it wouldnt hurt to get in in there... I had a similar situation with a 2000 nissan altima, it lost power and would idle ruff.... codes stated it was a sensor, but after really heavy research i found out it was a bad head gasket and had to pull and replace it.... air was leaking right at cylinder 4.... so sometimes the codes can be off as to whats really the problem. I also had loss of power on my 91 explorer and found out i had a tranny leak... my hoses had a crack going to the coolant system... i replaced them and added fluid and it pulled harder than ever.... im saying all this to say sometimes it something really small.... you had have to look for leaks, loose wires, vacuums etc.... if you have oil build up you may want to degrease and clean it and start watching for potential problems.