Emissions problem

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Mar 31, 2016 | 06:27 PM

#16

FuzzFace2

FTE Legend

Joined: Nov 2015

Posts: 30,830

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From: Angier, NC

Quote:

Originally Posted by Rusty_S

I couldn't say I think it depends on the model cause Ive seen some diesels at work given they are older and some were Chevrolets but they had vacuum brakes not hydroboost. I could not say on the vacuum aspect.

Like I tell my boss over and over again, I know the basic theory of operation but I am not a diesel tech.

I would like to know what ones they were just so I know but my 86 6.2 and others I have seen had vac pumps and hydro brakes.

Quote:

Originally Posted by 85e150six4mtod

With some exceptions there is no throttle plate in diesels. On old mechanical injection systems the throttle simply allows more fuel. With drive by wire it's the same except the fuel increase is computer controlled. Thus you can make lots of smoke with an old one by adding lots of throttle when under load. Diesel engines are set up to gulp as much air as they can. Thus dialing back the injector pump might be an answer here but unless there is a blockage in the intake more air is not to be had without a super or turbo charger.

You can set the old mechanical pumps up to inject more than needed fuel from idle on up.

My diesel did not make bost un-less you were under power. You could throw rpms up & down and boots gauge would not move.
The EGT gauge would move but that was it.
So at idle the turbo was not adding any more air to lean out the pump and why I think mine failed the state test after the pump was rebuilt and turned up for the turbo.

That is what I found with my chevy 6.2 with turbo
Dave ----

Mar 31, 2016 | 07:43 PM

#17

Rusty_S

Lead Driver

Joined: Apr 2007

Posts: 5,958

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From: Houston

If the one I know for sure ever comes back in I will make note of year/make/model and post it on here.

I know there is one for sure I don't know if the Izuzu boxvan we did had vac or not on the brakes but it was a 3 cylinder diesel.

Apr 1, 2016 | 08:47 PM

#18

Skagewa

Thread Starter

Freshman User

Joined: Oct 2015

Posts: 45

Likes: 0

From: Thornton CO

So I don't think that my vehicle has a throttle plate or at least I don't know because I can't find anything on the internet regarding it and my vehicle model.

I was reading about the turning the injector or fuel pump (excuse my lack of knowledge in this subject ) down so I can compensate for the altitude.
Can anybody give me some instructions on how to do this or would I have to take it to a mechanic to do it?

I also apologize for the delay on my replies. I've been busy with work and whatnot but I appreciate the help from everybody!