I'm Trying 2 Diagnose What Sounds Like An Slight Injector Miss W/your Help.i Took It 2 The Dealer,they Said #5 Is Weak(89%)all Other Cylinders R 105%.they 1st Replaced Thr Connector Tube,then The Injector.no Help Neither Time.i Have Perf. Nozzles And They Put The Same Nozzle Back On The New Injector.wondering If It's The Nozzle.they Thinks It's A Bad Cylinder.it Has A Little Black Smoke At Idle.should I Put A New Nozzle On , Or Let Them Do A Leak Down Test?anyone Have This Problem Or Have An Knowledge?

 

I'm going through this now. I learned from Bosch that swapping tips on injector bodies without pop testing and shimming to match flow rates across the injector group can cause a very rough running condition - in my case, especially at idle. I recently had all 6 injectors replaced with new, and the mechanic soaked and wiped my F2 nozzles, then transplanted them on to the new bodies. Ran like crap at idle and got worse within 500 or so miles. Replaced the injectors with a set of OEM (thanks to MASONIC DODGE for the bailout!), rig runs great now. F2's on the new bodies are on the way to DonM for pop testing and balancing.
In short, a crudded injector may have been the start of your problem, and the nozzle may be loaded - your best bet is to do the leakdown test to either confirm or eliminate the bad cylinder possibility - if the test checks out, then have the injectors cleaned, tested, and balanced professionally. I learned the hard way....

 

Thanks 4 The Reply.i Have New Nozzles, Just Contemplating Whether 2 Try One B-4 The Leak Down Test 2 Eliminate The Nozzle Or Not.i Don't Want 2 Wait Til Monday 4 My Appointment 4 The Test.