My truck has a bad miss at idle, up to around 1750 rpm's. The problem is intermitant. I can get off the interstate, sit at a redlight idleing, and the truck will be fine. I cna drive 20 feet and stop, and it will miss.

I have checked the coils, all are good.

i have replaced the sparkplugs. tr6 gapped at .37. br7 are not in.

I have replaced the IAC. no change.

I checked all vac hoses. All are good

I have unplugged every fuel injector 1 at a time and all make the truck run like crap.

checked the egr. all is fine.

I have run 3 bottles of fuel injector cleaner through the truck

My driver side o2 reads funny. It will read .7,.8,.1,.9,.6,.8,.2,.6,.9
ect... goes low for a split sec, then pops high, then low again a few secs later ect... The computer was throwing a code for o2 bank 1 lean, then it stopped throwing that code and now it throws o2 bank 2 lean, and o2 bank 2 rich. all codes are for sens 1.

the comp is on the stock tune right now.

A poss. i have been presented is a dirty fuel injector not coming clean. I have the price for new stockers and will purchase them if there are no other cheaper troubleshooting tips.

Any ideas?

 

How many miles on your ride? Any chance you have a bad O2 sensor?

 

24k miles.

 

has your timing chain every been removed? I had a miss, did all you did, then Sal pulled off my timing cover and when Ford replace the timing chain after replacing the heads it was off 2 teeth. He fixed it and the miss was gone. did you check the voltage on the coil pacs?

 

Consider a compression or leak down test?

 

timing chain has never been removed to my knowlege. Truck was used, but it has never missed this baddly.

I have considered both, and am looking for time to do them. But if it were internal, wouldn't it do this across the rpm range?

 

Copper plugs are a great thing......


Try a set of platnium plugs.

 

If you have not changed your Fuel Filter
DO IT,you may be surprised
Trust me, I know.....

BTW
Doesn't matter how old it is either

 

ttt