Emissions Question

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Jun 22, 2001 | 07:24 PM

treefort

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Emissions Question

Hello, I have a 1990 F250HD 4x4 w/351W(FI) and the ZF 5sp.
This vehicle is now a off-road vehicle only, no on-highway usage at all. My question is it still has all the emissions stuff on the engine, can someone please explain to me what I can take off and what has to stay, I know a lot about these engines but need help on this. Like unscrewing the hot air tubes that go into the exhaust manifolds and plugging the with pipe plugs or what.
and can I do this and still keep my check engine light off or will it always be on.
I saw a truck just like mine at the local garage getting a new EGR that was a electrical company truck that had all this taken off and the engine bay looks real clean, besides there are emissions sensors on my truck that are bad and I would rather do this to clean up the bay.
It is a strictly off road truck now,
and besides I am in Arkansas and there are no check anyway.

thanks,
Joel Thomas
1990 F250HD 4x4, 351w, ZF,
305/75/16BajaClaws.Ferndale,AR

Jun 25, 2001 | 11:29 AM

loudfords

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From: Beachville, Ontario

Emissions Question

I would say the smog pump and all related plumbing and hot air tubes into manifolds can go without negatively affecting performance. The EGR might be able to go too. You definitely want to keep a good O2 sensor in your truck because that can have a substantial effect on the way your truck runs.

Hope this helps.

1979 F150 Custom: nothing under the hood at all (again)
1987 F150 XLT Lariat: 88 351W EFI
84 351W: soon to have 91 heads, Crane PowerMax cam, double roller timing chain, Edelbrock Performer intake & Holley carb and be put in 79 F150
86 & 87 Bronco II: next winter's beater

Jun 25, 2001 | 11:49 AM

Franklin2

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From: Virginia

Emissions Question

Disabling the egr will definitely make the check engine light come on.

Jun 25, 2001 | 01:27 PM

treefort

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Emissions Question

The light won't bother me just don't want to screw something up.

Jun 25, 2001 | 02:05 PM

RGAZ

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Emissions Question

You can take the EGR off. Just plug the passages that go into the intake, vacuum, and the exhaust.

You can also re,move the PCV system. Plug the line into the intake. And get a vent for the valve cover.

And the air pump. Plug all passages and remove the pump.

Clean up the engine bay by removing now unneeded vacuum lines and plumbing.

it will look nice.

You should see a performance increase.

Randy

Oh yeah, lastly, you CANNOT remove the O2 sensor, your Engine management system needs it.

Jun 25, 2001 | 10:28 PM

Franklin2

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From: Virginia

Emissions Question

I wouldn't remove the PCV valve. This is actually a good thing believe it or not. It removes harmful vapors and condensation that can build up in the crankcase. When this mixes with the oil it forms an acid that is hard on the bearings of the engine.
If you are going to take all that stuff off, I don't see what difference the O2 sensor will make, since with the check engine light on, you might be in open loop where the computer doesn't use the o2 sensor anyway.

Jun 25, 2001 | 11:10 PM

treefort

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Emissions Question

Well I did it and it does run a lot better but not enormously better, I left the 02 sensor in becuase I thought that it wa the measurement of hot to deliver the fuel so it needs it to precisely measure the amount.

thanks for all the help,
Joel Thomas