<o></o><o></o>I have a 94 with a 351w all stock with the exception of a K&N filter and MSD coil. Now my problem is that when I am at idol the truck seams to miss but under acceleration and normal driving the truck runs great, only misses at idol. Any ideas on what I can look for to make this stop? Thanks for the help in advance.

 

I would look into cleaning the IAC(look in your service CD or manual).....BTW..does it "miss" only when its cold....or after it reaches op-temp also????

 

it will "miss" at all temps.

 

CHECK FOR CODES, let the ecu tell you whats wrong before you start throwing parts at it. now streetgang is probably right , could also be a bad tps but codes should always be done first.
www.fordfuelinjection.com explains how using a paperclip an 10mins of your time

 

well i just did the test and it is giving me this code #33 "EGR valve opening not detected". so does this mean i need to replace the EGR or can it be cleaned? Thanks again for the help this place is awesome.

 

well first replace the sensor on top of the egr because it could be faulty and giving that reading. if that doesnt cure the code then yes an egr would be need and its a part that you always buynew

 

Check the electrical connections first for EGR and IAC. My bet is the IAC. Had the same problem on my 5.0 Mustang.

 

Check the vacuum lines that run to the egr valve. Vehicles around 10 yrs old are prone to weak dry vacuum lines which crack very easily. I am having the same issue with my Bronco and some techs are saying it may be a weak booster fuel pump at the frame rail. Check the pressure in the fuel rails and see if you are at 45-50 psi. If not, it may be a booster pump or the diaphram on the fuel rail is bad causing a lack of fuel pressure and a lack of fuel for that matter causing poor detination in the cylinder. EFI vehicles can be a pain most of the time. OH! DO NOT USE THOSE CHEAP SCANNERS FROM WAL-MART, PEP-BOYS ETC. MY TRUCK STILL THROWS 33 & 133 USING IT. I JUST GOT A SNAP ON AUTO DIAGNOSTIC SCANNER FOR LIKE 1200 BUCKS AND IT READS NOTHING. Could possibly be somthing mechanical causing a false reading at the egr valve.

 

45-50 for fuel pressure is hi it shouldnt be above 45. 35-40 is about right

 

Yeah you are right Kem. Thanks!