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Discussion Starter · #1 ·
Trying to track down a problem with a 94, 351/e40d bronco.

When the truck is idling, and you shift it into gear the idle is low, then when you give it gas it stalls out....it seems to run better when its cold, open loop.
So far we just installed a new 02 sensor, new plugs, wires, cap, rotor and verified tps is working....any other ideas?

Truck was running great, then we added a full 3" exhaust with no cats and headers, hot air intake, plugs, wires, cap, rotor, deleted egr and held sensor 1/2 way in, new 02 sensor, and changed fuel filter.....so it HAS to be something we changed.....? any ideas?
 

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Satyr of the Midwest
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well...

getting rid or the EGR can effect the idle and the way the engine performs unless you "fooled" the computer into thinking that the EGR was still functioning at least that's what i've read in a few other forums
 

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Discussion Starter · #4 ·
yeah, we fooled the egr. We removed the actual valve and held the sensor plunger 1/2 way in to eliminate a ce light
 

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Why remove the EGR? :shrug

I've got another idea... pull codes. I'd think you'd have been here long enough to not have to be told that one. :goodfinge
 

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first i would start by reinstalling all of your egr components, an egr valve does not hinder performance in any way, it reduces nox and lowers combustion temps, so if anything it helps your engine and also produces less emissions, an egr valve is not open at idle, if it was the engine would run extremely rough and stall out. by pushing the snsor halfway in (not exactly sure what youre talking about) you may be confusing the engines computer, reinstall the egr and see what happens,
 

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EGR does matter for performance. Think of the heat that is added back into the system. Anywho, it sounds like the computer is messing up from the EGR change. It actually sounds to me like the chain jumped a tooth. But you say it idles and then dies when you give it gas? That sounds to me like the computer is taking something out of the system from the change. Did it run right before you put all that stuff on?

Chris
 

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Satyr of the Midwest
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That has got to be the worst way of disabling EGR I've ever heard of. Either get it working properly, which is going to give you the best driveability, power, mileage, etc., or disable it properly. I'm not going to help you do the latter; I like my clean air, thanks. There is absolutely no reason to disable EGR on any modern(ish) EFI vehicle where the PCM is controlling it.
 

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the egr valve sends only a small amount of exhaust gas mix with the air/fuel charge, turn one over and look at how small the pintle valve is. now take that small amount and divide it between 8 cylinders. youll neverfeel a power gain with the egr disconnected, at least i never did on any performance application. most guys get rid of it because it looks complicated and its not pretty to look at. but it does help your engine, ask any auto tech that does emission testing. plus since when is cleaning the air we breathe a bad thing?
 

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Discussion Starter · #11 ·
just figured i would follow up. Turns out it WAS the egr.... I never had a problem keeping it halfway in on my mustang or my truck (which now I have disabled completely), however his truck was more sensitive i guess....looking into resistors now....anyone have a diagram?
 
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