hello
my truck now has 202,000 on it with a new jaspers motor at 167,000. I started having an issue this weekend that I cant seem to figure out. the truck will start running a little rough, feels like its lurching some, I step on the gas and get the rpms up and it goes a way, does it at idle and just crusing down the freeway. I changed the fuel filter , didnt help. I am going to put a fuel pressure guage on it and try to run a diagnostic with a freinds computer but i am not getting any lights on the dash. if it was the fuel pump wouldnt I get a code, and since there is no code that eliminates maf sensor and coils and plugs , correct? Im stumped, any help would be appriciated
Fred

 

It would not hurt to clean the MAF, IAC, and throttle body. Is this a 4.6 or 5.4, and does it have COP's or coil packs and plug wires? Do you know what brand of spark plugs are in there?

 

check you coils plugs and wires my dads truck was doing the same thing and its a 4.2 v6 2000 model it was carbon on the plugs if your not throwing codes its nothing to major just annoying as he** let me know what you find out bro

 

logically it would seem correct on the plugs throwing codes but unfortunately it doesnt always work that way i launched a plug out of the head and completely shattered a coil pack and never got a code one ran rough as he** and sounded like a stock car but still no code easy fix though so no biggie oh its a 2002 screw 5.4

 

cop, 5.4. Im leaning towards the fuel system, since the problem goes away as the rpms come up and its intermitent. I am going to look at the regulator and fuel pressure tonight. I plugged it when I drove to lunch and watched alot of data, the the cyliders were all firing ok, but I couldnt read the fuel pressure through the obd 2, so tonight I will put a guage on it

 

wnet through all the fuel system and all was normal, after 5 days of running bad intermitantly it finaly threw a code, cyl 1 misfire, pisses me off that it took so long