whats goin on everyone? fan of the forum has alot of helpful knowledge on it. so this thread isnt to long heres the short story of my situatioin... i have a 95 f150 that is giving me some grief right now in tracking down the problem. about 6 months ago when i got it i noticed that when going speeds above 65 it would sometimes hiccup going down the highway sometimes just 1 or 6 in a row. just recentley it overheated and now is doing it pretty much in every gear, it feels like someones first time on a clutch. so i scanned it and the codes it pulled were for a couple sensors and port 1 being clogges, i changed the sensors and it is still running rough and i dont know what a clogged port would be. would appreciated if someone could shed some light.

 

Welcome to FTE.
Do you still have the codes that you pulled?
Could be egr related, but that's just guess without further info. Any tune-up performed? Let us know.

 

I do not have the codes anymore unfortunately, I am going to try to get them up tonight and if I can't ill have the up tomorrow. As far as time up goes I have changed the wires, plugs, cap and rotor. Changes the rear fuel pump along with the fuel filter and changed the oil. Replaced the o2 sensor along with the temp/air sensor and ignition coil. I think that pretty much sums it up

 

The map sensor was bad on my 95 4.9
Threw a 179 code. Replaced it, and it stopped "hiccuping"

 

Dusty made a good point with the MAP sensor. Also when changed sensors with new ones, did you disconnect the battery long enough to erase learned settings. If not, then you should do so, drive it for a minimum of 5 miles @55 mph, varying the throttle. That's what the Ford manual says says to do, to adjust and compensate for wear and new sensors after repairs are made.

 

Well I wasn't able to get it scanned today, it was a busy day. Will get those codes tomorrow and see if I didn't miss anything. Thanks for the help so far!

 

so i pulled codes 112,172, and 173 tried to find whats those codes ment but was unssecesful i dont know if anyone else has pulled those codes and know what they are. oh and i replaced the map sensor, but she still has loss of power and is gerky in gears 1-3.

 

Code 112 is a vacuum to sensor problem, check for bad vacuum lines, or a rusted through reserve can

172, 173 is o2 failing. 172 is lean, 173 is rich

 

i looked for some vaccum leaks and didnt find anything. all the vaccum lines look like they are in decent shape. i believe when i scanned it the one code it pulled for me was 112 saying i had low voltage on my air temp sensor, so i replaced it but still pulling that code and i dont think a bad o2 sensor would make my truck run the way it is runnin?

 

Several thoughts here... Low voltage to the iat sensor, could either be bad wiring or a problem with the connector. It is a must have when truck is running in open loop. If it and the O2 sensor are not getting, producing or sending info, truck is gonna run like poop. Check reference voltage for the IAT and the O2 sensor. Should have 5v @ IAT and 12v @ O2. Check all grounds.

And as dusty mentioned, check vacuum canisters under washer fluid box and the one nearest the passenger side wheel well, near battery. Known to rust through and cause major vacuum issues. Stick with checking the wiring leading to the IAT sensor, sense the ECT seems to not be coming up in codes. Wouldn't hurt to check the voltage either at the ECT to see if you are getting good reference voltage.

 

Well gave it a really good look through and none of the canisters are rusted through all vacuum lines seem to be in good condition. However I did pull the plug on the top of my IAT sensor and there was water In it ( don't know how it got there). So I cleaned that up and I was curious to see how it would run without that plugged in. So I left I unplugged and she ran great, ran like it was a million dollar truck. Turned it off and then it wouldn't start up again, then plugged it back in and started running rough again! So It has me thinkin it's in that harness... Any other ideas?