Injector help please

[bubtheman]

Quick question. on a 99 powerstoke what is a good way to isolate a bad injector. I will replace all later but i'm broke and i really need to use to truck. so i want to replace the bad one now. Anyway to find the bad one without a trip to the shop??????
any help with this will be greatly apreciated

 

[Mike]

Buzz test.

 

[Cass]

If the truck can run, you can get a cylinder contribution test done and also the buzz test 95 Stroker had said. You can also take a thermo temp gun and check the manifold temps. Now there will be a variation from one exhaust port to the next but what you would be looking for is a big drop in temperature. Now the last would be to take the vavle covers off. With the truck running, you can pull the connectors from the solenoids (top of the injectors) and listen to the engine. With a good injector, the idle will change enough for you to recognize. With an injector that is not contributing that well, you will hear a slight change to no change at all. If you pull enough connectors your ear should be able to pick up the one that is missing.

 

[bubtheman]

thanks guys i know running the truck w/o valve covers is ok but what about the intercooler lines, should i put them back on??

 

[Cass]

The truck will be OK with the intercooler tubes off.

 

[silverado3500]

What exactly is the Buzz test, and whats involved?

 

[Doggy Daddy]

Buzz Test is a function of a scan tool. I've used the Ford STAR tester but I thing that the generic scanners will do it too. I think it will only sense an electrical problem, not if there is a mechanical problem with the injector. The infrared thermometer on the manifolds sounds like the easiest at home test.

 

[BJS]

If you're poor and don't have the fancy toys to run the buzz or cyl contribution test then since you have the engine running w/o vc's right now you can simply unplug each injector and see which one makes the least difference. I had some that were bad but were still firing but not completely so I couldn't tell this way but it'll work if you have a really bad injector.

 

[wanderer]

I used a heat gun on the exhaust manifolds to isolate my injector problem. I ended up having 2 injectors that were clogged. I pulled all four injectors and took them up to Swamps, and had them back in the engine that afternoon. I apparently let some trash get thru when I changed the fuel filter.

 

[silverado3500]

I assume the colder cylinder(s) are the ones that are likely to have a bad injector, also, whats a good place to get an IR thermometer?

Thanks

 

[Mike]

I assume the colder cylinder(s) are the ones that are likely to have a bad injector, also, whats a good place to get an IR thermometer?

Thanks

Correct, the cold ones arent firing and I think you can get an IR gun at NAPA or AutoZone or the like.

 

[Doggy Daddy]

I think that the PCM is really a marvel and it can compensate for weak injectors (at least at idle), like the results that BJS got. As I recall every time I have considered buying an ir thermometer they have been ~ $80 and up. Seems like I usually have something more important to buy.

 

[silverado3500]

Correct, the cold ones arent firing and I think you can get an IR gun at NAPA or AutoZone or the like.

Great, Thanks for the info.

One last question, what would be the ideal place to shoot take the temperature? Should I be going for the exhaust port, right where the manifold meets the block?

 

[Mike]

Great, Thanks for the info.

One last question, what would be the ideal place to shoot take the temperature? Should I be going for the exhaust port, right where the manifold meets the block?

I would shoot the manifold just down off the head maybe an inch or so, that way you dont pick up any radiant heat from the head.

 

[silverado3500]

Great, Thanks for the help