2002 Duramax injector questions

zeke392 · June 10, 2014

My son recently bought an 02 Chevrolet Duramax / Allison 4wd used with 128,000 miles. He is 2nd owner and the truck has been stock it's entire life. He put a 4" MBRP exhaust on the truck 2 months ago deleting the muffler, and recently bought an Edge monitor for it, no tunes. The neighbor told my son that he sees white smoke in the exhaust so he has a bad injector. My son checked the injectors at cold start and 6 are within the recommended 4 range, 2 are beyond that around 6. We see a haze in the exhaust but I don't see white smoke. I have never owned a diesel before.

1, What is he checking, injector psi?

2, If you don't have the Edge monitor, how would you know you have a bad injector?

3, When does he take the plunge and spend the money on new injectors?

Any help and advice is greatly appreciated.

Thank you,

Steve

zeke392 · June 10, 2014

Oh yeh, we just took it on an 800 mile round trip in 2 days running between 70 and 80 all the time no load, no trailer. He averaged between 18.5 and 20.5 mpg with no issues, in my opinion flawless performance. Considering this, I find it hard to believe that he has any problems with injectors.

Prokopchuk_9 · June 17, 2014

Those injectors are on the way out, you could try to remedy it by doing the "gm injector cleaning" magic juice. It's been known to being rates back a little bit. But either way, start Savin some cash. If you're gonna run it, be very careful if those cups are leaking you will collect fuel in the crankcase. Check your oil continually if it's "making oil" shut it down. You'll spin a bearing or melt a piston, as it is white smoke on start up is only the beginning. It's not a matter of IF you gotta replace injectors it's WHEN.

And when you do, I suggest a lift pump like a fass system or air dog. Air cavitation and GM's poor filtration system is a contributing factor to lb7 injector failure. It's NOT a cure, but will help. A lift pump removes air from the fuel, water and you can run a 3 micro filter. And when you replace them, do it right don't skimp out on cheap parts like washers and injector lines. Since it's an 02 I would do head gasket at the same time for peace of mind. Because it probably doesn't have the grade c gaskets. But that's just me.

When he is checking the balance rates, is it up to operating temp in park? If not, try again.

Sorry to say, but this is a very common problem with 01-04 lb7 Duramax trucks.

Also running power service or a good additive in EVERY tank will help lubricate and keep the nozzles clean. It will help with injector like a little bit.