I will be glad to remove the radiator if this is the problem. I've been dinking around with it all week and I'm itching for a solution. (Hopefully an inexpensive solution; I don't think balancers are too pricey.)[sm=burnout.gif]

 

Last time I bought one was several yrs, ago thru FORD , think it was like $80.00 ?, Well should be ppl here on an off Tomm. so if you can , or get stuck somehow . Come on back An we'll see what we can do .

 

Thanks for the help! I'll let you all know what I find.

 

My '99 F-150 has a little bit of a shake to it at that rpm range, but its only at idle. When you are driving with the engine between 1,000-1500 rpm it doesnt shake.
Octane

 

I checked out the balancer, and it seems to be fine. I pulled each plug wire off individually while the engine was running and I found that there was one cylinder that didn't effect the engine idle when I pulled the plug wire off. I pulled the plug out and started the engine and it had spark, but there wasn't any fuel/air mixture that came out of the hole where the plug was. I put some injectoer cleaner in the tank and drove for a while, and it seemed to get somewhat better, but not perfect. I filled the tank after driving and put more cleaner in. I will see if this makes a difference, but I'll have to hook up to a computer to see if I'm getting a code for this.

 

Wouldnt be the first time I had a bad spark plug that wouldnt fire under pressure, but spark ok outta of the motor . Back in the day we had a plug tester -- that basically put the plug under a load, An it had a window to look through to see the plug was firing. You dont see them these days !!!!!. And your only going to get a TINY bit of fuel outta a cylinder, Its not like you can crank it over an see a mist coming out . , An its quite possible you got a plugged / bad injector , probaly the best thing you can do is go an get the fuel system flushed , I think its like $ 80.00 bucks these days , will make a world of diff. in the way it runs . !!!

 

I wouldn't think that the plugs won't fire when under pressure because everything from the coil to the plugs is new, but that doesn't mean it isn't happening. I still want to see what kind of codes I get from it. I think a fuel system flush would be a good idea, too. I did use it again today and it is running MUCH better, but not perfect. It still wants to shake sometimes, but only around 900-1100 rpm. It isn't as intense as it used to be, either. I will let everyone know what I find with the codes.

 

Will then the code is going to be missing fire on # cylinder, or random misfire. Its best to have a shop do the injector cleaner. They have to shutoff fuel pump and tie in to the fuel line with the injector cleaner machine.

 

Had the same problem! My 98 would almost go dead when stopped at a red light. I had a vacuum leak. Real difficult to find. It was on a 90 degree rubber boot located on the bottom side of the intake manifold, at the front of the engine. It appeared to get hot and literally melt. A mechanic qouted me a price of 200$. He said the manifold would have to be removed to make the repairs. I was able to change the boot myself with a little work and didn't have to remove the manifold. It was real tight but definately capeable. I think the mechanic was trying to make some easy money. The part cost $12 at the dealership. The counter man knew exactly what part I needed, as if he had sold a few.

 

I inspected the vacuum lines once already, but that doesn't mean I missed or overlooked something. I did buy a code tester the otherday, and I plan to use it tonight. I will keep everyone posted.