01 v10 running like crud

[oldkountryboy]

alright guys i need some help on where to start here

background 2001 v10 110,000 miles, k&n , gibson headers, true duals,

i had been running a superchips 1715 programmer but did not notice much difference so i sold it after i put the truck back to stock and it ran great a few months

now it idles fine and around town it seems to run good but when i get on the road it runs like crud you can feel it hesitate and not want to pull
but i do not get a check engine light

so where should i start

i replaced the plugs and boots about a month before i took the programmer off

[oldkountryboy]

also my fuel mileage went from 10-12 down to 6-7mpg

[bigblock_drock]

clogged fuel filter? maybe clean the MAF also.

[juterbock]

I replaced the fuel filter and went from 12 to 13.5 MPG on my 108k milage 2001 V10. I've got a new set of O2 sensors in the truck and plan to clean the MAF again and then reset the computer and see what I get on this tank. Spark plugs are in the works either this coming or the next weekend.

[rvpuller]

The first thing I would do is the fuel filter and then the MAF.

Denny

[oldkountryboy]

thanks guys, i will change it in the morning

[Skoda]

please do report back with your results, I to am running 6 mpg and not one bit happy about it

[oldkountryboy]

well i quit driving mine everyday a few months ago, i got lucky on a deal for a 92 mustang with a 4 cyl for 500 bucks, so i have been saving over 200 a month by driving the mustang i love my truck and my v10 but with 44s and gas being as high as it is and i was using at least a tank a week and sometimes more
needless to say it has paid for itself several times over

[oldkountryboy]

sorry it took so long to get back to you guys, thanks for the ideas but the fuel filter and cleaning the maf didnt help, i borrowed a friends temp gun and checked the headers after it warmed up for about 15 minutes and the passenger side bank is not running the same as the drivers side, drivers side temps right at the exhaust on the headers was running from 230 degrees C to about 275C, and the pass. side was anywhere from 90 C to 150 C

the only two things i can think of would be the O2 sensor and maybe a head gasket
can yall think of anything else that would cause one bank to be so much different than the other ?

[Skoda]

I'd pull out the good old obd2 scanner, check for any codes, if your lucky it will be one or some cop's, if thats not the problem then I'd reccomned doing a compression check ( if theres a miss fire due to a blown head gasket there will be a code present**even though the check engine light is not on**)

A possible quick tip would to manualy turn your motor over, and listen for escaping air, take off your pcv valve, radiator cap and see if theres bubles coming from either.

Hope its nothing serious, best of luck
Skoda

[oldkountryboy]

well here is an update guys, went to 2 different parts stores and neither would try and read the codes because the check engine light is not on
so i went with my gut and bought a passenger side O2 sensor and man a huge difference
it is still not perfect so i am going to order another O2 for the drivers side and 10 COPs and thinking of putting in new injectors, i have a spare set i think i will put new filters and o-rings on all that should put me running smooth and strong again

thanks again for the help and advice guys

[juterbock]

That is probably some serious overkill to replace all of your COP's and injectors. I've never done it but they say to run Techron through your fuel system and it will clean out the injectors quite nicely. And if you think one of your COP's is bad, get the OEM replacements (1 of them) and then swap it out with each of them. If the engine runs better after a particular swap you know you found a bad COP.