5.9L injectors question.

[BigPapa]

The Cummins doesn’t do free revving well. It only runs well in the higher RPMs under load. Totally different from a gasser.

 

[Blakers]

The Cummins doesn’t do free revving well. It only runs well in the higher RPMs under load. Totally different from a gasser.

I agree. I was having some vibration issues a couple of weeks ago (turned out to be a rear u-joint), but in playing around with ideas in my over-complicating things head, I noticed this issue.

 

[Ozymandias]

Mine drops down in stages when brought up to 2500-3000 rpm (in neutral) and let off suddenly. Otherwise, no issues. Starts great. 195,000 miles.

Mine does that too, even with the BBi's in it.

 

[Blakers]

Mine does that too, even with the BBi's in it.

THANK YOU!
That is good to know.

 

[promisedland]

Mine does that too, even with the BBi's in it.

Really? My bbi .05s drop smoothly.
Which size injectors do you have?
.

 

[Blakers]

I have no idea what I currently have in my truck as I only bought it in March. I’ve assumed it’s stock, but it runs really strong, and will get up and go and smoke if you get on it. Runs up to about 3000 and shifts if you drive it that way. I plan on a Smarty Jr, but no tuner yet, unless it’s had something programmed in.

 

[Ozymandias]

Really? My bbi .05s drop smoothly.
Which size injectors do you have?
.

I've .1 or standard 120k old.

 

[Ozymandias]

I have no idea what I currently have in my truck as I only bought it in March. I’ve assumed it’s stock, but it runs really strong, and will get up and go and smoke if you get on it. Runs up to about 3000 and shifts if you drive it that way. I plan on a Smarty Jr, but no tuner yet, unless it’s had something programmed in.

Wild guess is you have a tune on it already.
Because, no matter what I do to my truck - with the factory tune there isn't even haze from the pipe. Changes when I program the Smarty tunes.

 

[AH64ID]

Wild guess is you have a tune on it already.
Because, no matter what I do to my truck - with the factory tune there isn't even haze from the pipe. Changes when I program the Smarty tunes.

A guy I work with has a 05 he bought new that’s stock, he can make it smoke where in never could with my 05. So it is possible, but I don’t think it’s common. The HPCR’s run pretty clean in stock form.

 

[Blakers]

A guy I work with has a 05 he bought new that’s stock, he can make it smoke where in never could with my 05. So it is possible, but I don’t think it’s common. The HPCR’s run pretty clean in stock form.

It will lay down a cloud of black smoke if I really get on it. Not as much as my stock 03 would do with the van Aaken box turned up. But it’s definitely more than a haze. I’ve seen no smoke or haze with normal driving.

 

[Ozymandias]

I had something similar when my Turbo was on it's way south, couldn't spool up anymore like it should.
Once up to rpm it was fine.
Clogged air filter is also similar.

 

[Blakers]

I had something similar when my Turbo was on it's way south, couldn't spool up anymore like it should.
Once up to rpm it was fine.
Clogged air filter is also similar.

I get 30 psi of boost. New air filter.

 

[Ozymandias]

I get 30 psi of boost. New air filter.

Me too, top end was fine. Problem was only the spool time in my case.
Just a slight delay there has a big impact on smoke if the boost build lags behind what the ECM expects to see at any given moment during this time.

But I said, more likely your truck has a tune already.

 

[White2005]

My 2005 could smoke when stock, and still can with stock program.

 

[White2005]

My 2005 could smoke when stock, and still can with stock program.

I am also rarely below 4500’ elevation…