A FTE regular was kind enough to hook my truck up to his AE scanner this weekend.

For some reason, we were unable to perform an injector buzz test.

Has anyone else experienced this? If so, is something on the truck malfunctioning so as to cause this?

 

Was the engine up to operating temperature? If the oil temperature is cold (and it takes quite a while to warm up), the test will not run.

If I may ask, why do you think you need to perform that particular test anyway?

 

I think the buzz test works when cold, it's the contribution test (perdel readings) that don't.

What exactly did AE say when he tried to run the test? Was it able to pull any codes or see any live data?

 

Sorry Cody, I can only guess the coffee hasn't kicked in yet. It is recommended the buzz test is first done when dead cold, then done again at operating temp.

Here is a dead-cold buzz test.

Stinky Injectors.MP4 - YouTube

What did the software do when you clicked the button for the test to start?

 

The truck wasn't cold, oil temp was a little under 150. When I clicked "initiate" it went in to the test, but after a bit the screen said "unable to complete" . It had the P0603 KAM error code, and a low boost code (p1247). The truck has a little exhaust leak, that might explain the low boost code. David has the live data numbers written down so we'll have to wait for him to see those . No injector codes, no misfire codes, etc... The truck runs fine, it just has a case of the romps on cold start.

On edit: 220 some-odd thousand miles on the truck.

 

What year truck was it? I have had some issues with the older trucks playing well. Usually the Buzz Test isn't a problem though. Was AE set up manually or automatically?

Also always make sure the heater controls are in off before running tests. With a Buzz Test, I doubt it would make a difference, but some of the other tests will fail. Mostly because the AC clutch cycling. It is published in the manuals to have it off.

 

Cleatus12r - I ran the test because the mechanic I had been using suggested I need to replace the injectors. As SteveBricks pointed out, I have the romps on startup. However, I think the problem is more than just romps. The truck is here in CA where it doesn't get below 45F and over the last few months, the truck has been VERY difficult to start when sitting for a few days. The starter cranks, but the truck doesn't start (as if there is a weak/dead battery). Once it does start (typically after several attempts of wIting for the glow plugs, turning the key, and then waiting for the starter to cool), it has the romps, and often stalls. It often requires me stepping on the gas pedal to first get it started, and then keeping it running. Once in drive, it then lacks power on acceleration for the first few miles/minutes of operation. (I did notice the tach will rev but no power). Thus, my unexperiences opinion is that there is a fuel delivery problem.

By way of history, the truck has a new fuel tank, sending unit, fuel pump, the fuel bowl was rebuilt, the hutch mod was done, and a pre-pump fuel filter was added. The fuel pressure is (I believe) 55lbs.

Woodnthings, the truck is a 2001. The heater was on in the cab when we attempted the test.

Thank you.

David

EDIT: the truck runs fine after it heats up and will even start with no problems later in the day after being run that day.

 

My F-450 had the same symptoms as above. 190k miles and I presume most all of it was towing heavy due the way the previous owner had set up the truck. I sent my injectors to Rosewood Diesel for a quality rebuild using brand new (stock spec) nozzles. It ran me a little under $900 for the work. Now the truck runs excellent and has plenty of power to spare.

I have had VERY good luck with injectors rebuilt by Rosewood for my personal trucks. Those trucks run stronger and idle smoother than our fleet truck on brand new Alliant injectors. People will say I am crazy but I'd probably choose having my original injectors rebuilt by Rosewood vs a set of new injectors right out of the box. I know that Jim at Rosewood takes some extra time to carefully test his work and tries to balance them as a set. I think that makes a big difference in how well the engine runs.

Be advised, worn injectors can easily pass the buzz test as well as a contribution test especially if they have all degraded at about the same rate. The buzz test is best used to test for electrical issues and solenoid/poppet operation. A buzz test can not tell if there are any problems with the plungers, barrels, nozzle springs etc. It also can not tell if the nozzles are flowing to spec or if the poppets are holding high pressure oil.