My '94 with 2.3l, dual ignition. always starts reliably...runs good and smooth for a minute or two...then runs really rough for a minute...then smooths out again and is fine. If I start driving "before" getting through the rough time, the engine will bog down and backfire for the same time....not a good thing while driving. Other than this problem, the truck is great and runs reliable, Anyone have any thoughts about what might be causing this momentary roughness?
Thanks.

 

bump, same thing happens with my truck, '95...takes about 30 seconds to a minute or so, runs fine from then on.

 

My 3.0 does the same thing and i have not found a fix for it.

 

clogged fuel filter??

 

actually I just changed the fuel filter not long ago and just recently cleaned the MAF

 

I had that same "ruff running" feel with my 07. The back of the throttle plate gets carbon build up near the rim. I used some paste type hand cleaner on a soft bristle tooth brush and cleaned the build up off it. I wiped off the cleaner with a new shop rag...wow....lots off build up in only three years. Idles smooth now when I'm stopped at red lights, no noticeable ruff idling now.

 

What's involved to clean the throttle body/ (butterfly)? Did you have to remove it? I suspect I have similar issues and just wish to get some idea what I'm in for. Also, If I have to remove it do I need to get a new gasket or anything for re-assembly?
Thanks,

 

Reaching it was the hard part, remove all the plumbing for the air intake and find a used tooth brush. You can hold the throttle plate open by the throttle linkage cam or your with your finger. Oh yes ...the engine is off for this one!!!! Dap a little waterless hand cleaner (non-pumice) on the bristles and rub it on the underside of the plate. Carbon builds up on the rim of the plate and restrict air flow it housing body. Use a clean cloth to remover the soiled cleaner. It will surprise you how built up it can gets on the plate. Most people spray a carb cleaner in to it but its not all ways a direct line or it will set off a "CHECK ENGINE" light. This way is safer.

 

Thank you, I'll give it a try this weekend & let you know.

 

Hmm having the same problem on my dads 92 F-150 have already cleaned the ENTIRE intake iac valve ect still the same thing. As long as you let her run for 10 mins all will be well but if you dont.....well bucking kicking screaming ect.

 

i had the same problem on my 94 and it turned out to be the pcv

 

I did some diagnostic work on mine and got an "EGR signal out of range" code. So...I think I'll take off the throttle body and clean the vac. passages. Hopefully that will do the trick for me.