EGR cripple...not delete (3 Viewers)

[desertwampa]

Quick question for those in the know.

I'm going to install the CEL resistor mod for EGR. I don't want to remove the EGR parts just yet, but I do wanna turn that sucker off to prevent the carbon and heat issues that apparently effect cycl. 5 and 6. Anyway, what is the easiest and quickest thing I can do to stop it from operating? Then, If it is not functioning, do the hoses need to be plugged/capped, or can they remain open? Not sure if air will effect the engine if i leave them open/uncapped. If i do cripple it, will leaving EGR valve in place and not sealing the valves (wits end keychain) have any adverse effects? I guess the EGR cripple wlll essentially prevent air from getting in to the engine, ya?

In my head. I'm imagining that I can just take one step so that EGR doesn't work anymore, and then install the resistor mod so the CEL doesn't come on, and Wa-la. Done.

 

[Devils Paw 80]

You just need this. 1995-1997 FZJ80 EGR Temp Sensor Test Plug Kit - https://huddexpo.com/1995-1997-fzj80-egr-temp-sensor-test-plug-kit/

And maybe a couple vacuum line caps rather than BBs. Don't have to remove anything.

 

[desertwampa]

You just need this. 1995-1997 FZJ80 EGR Temp Sensor Test Plug Kit - https://huddexpo.com/1995-1997-fzj80-egr-temp-sensor-test-plug-kit/

And maybe a couple vacuum line caps rather than BBs. Don't have to remove anything.

yep, its on the way

 

[sjpitts]

I have wondered about that--- but it appears to me that the EGR valve will always be leaking out exhaust gases unless you do something serious to block it. Just blocking the vacuum lines that control the EGR valve does not stop the gasses from coming out and burning up your wiring harness (see the red line in the picture below). And I am not sure if a BB is enough to stop those gases. I once considered JB welding the EGR valve opening to seal it off, but I never did.

See this thread



ne

 

[sjpitts]

I have also wondered if you can buy one of Wits End's keychains that fits the EGR opening, and then install the keychain "under" the EGR pipe. That way the hot gases are blocked at the port, but the required equipment remains present for inspection. But you may not be able to do that without the head removed.

And one more thing-- I believe I read that someone blocked off the inlet to the EGR valve with a quarter or something placed between the EGR pipe and the EGR valve). That would seem likely to work. But I don't know for sure if it would or if it has ever been done.

 

[baldilocks]

In addition to vacuum hose disconnects I made a block off plate of .040” thick aluminum and placed it between egr valve and intake plenum.

 

[ZackR]

I have wondered about that--- but it appears to me that the EGR valve will always be leaking out exhaust gases unless you do something serious to block it. Just blocking the vacuum lines that control the EGR valve does not stop the gasses from coming out and burning up your wiring harness (see the red line in the picture below). And I am not sure if a BB is enough to stop those gases. I once considered JB welding the EGR valve opening to seal it off, but I never did.

See this thread



ne View attachment 3568642

FWIW it takes barely any effort to secure the wiring harness away from the EGR pipe, even a small air gap is enough to separate the two from damaging heat transfer. I haven't checked the temperature but I doubt the pipe gets very hot once the EGR is disabled since there's no exhaust flowing through it, rather its a dead end in the system.

Next time I drive the cruiser I'll see what the temp is and report back (mine is disabled but still intact).

 

[sjpitts]

FWIW it takes barely any effort to secure the wiring harness away from the EGR pipe, even a small air gap is enough to separate the two from damaging heat transfer. I haven't checked the temperature but I doubt the pipe gets very hot once the EGR is disabled since there's no exhaust flowing through it, rather its a dead end in the system.

Next time I drive the cruiser I'll see what the temp is and report back (mine is disabled but still intact).

I would be interested to see what the temp is with it disabled.

Cause If you look at the image I posted I think it is not clear that there is "no exhaust flowing through it" when the EGR is disabled. Instead, it appears to all be directed out of the EGR valve and towards the EGR modulator--- all the time. And this is why the EGR modulators sometimes blow up after the EGR is disabled.

But that is just a guess on my part

And one other thing-- maybe you are right about the harness, but the 93/94 wiring harness is NLA, and who knows when the 95-97 will also be NLA. So I would think anything that you can do to minimize the heat on the harness is a good thing.

 

[baldilocks]

Don’t over think it. My block of partition didn’t cause a modulator problem. Or ask yourself; how much exhaust flow actually gets past a disabled egr valve? If it were enough to matter your idle would be rough.

 

[desertwampa]

I would be interested to see what the temp is with it disabled.

Cause If you look at the image I posted I think it is not clear that there is "no exhaust flowing through it" when the EGR is disabled. Instead, it appears to all be directed out of the EGR valve and towards the EGR modulator--- all the time. And this is why the EGR modulators sometimes blow up after the EGR is disabled.

But that is just a guess on my part

And one other thing-- maybe you are right about the harness, but the 93/94 wiring harness is NLA, and who knows when the 95-97 will also be NLA. So I would think anything that you can do to minimize the heat on the harness is a good thing.

"Cause If you look at the image I posted I think it is not clear that there is "no exhaust flowing through it" when the EGR is disabled."

What if you just delete whatever hose/port is the one that supplies exhaust to the EGR valve? seal it/ cap it whatever. This way the EGR never gets the hot exhaust?

 

[LC4LIFE]

The 'Test kit' plug will disable the EGR. The BB's are there to prevent the risk of a vacuum leak, just in case something around there is awry. Like @baldilocks said, if the EGR was stuck open, the idle would be all wonky. Simply disabling the EGR gets rid of the majority of the heat near the harness, the rest is likely heat soak travelling through all the metal in the area. If I remember right, although I should probably re-read the FSM, the exhaust does not get past the EGR (like the drawing in post#4) and up to the modulator unless the EGR opens. That opening is based on a variety of things, engine load, coolent temp, speed, etc. My kit stops it from opening. And yeah....don't overthink this.

 

[desertwampa]

The 'Test kit' plug will disable the EGR. The BB's are there to prevent the risk of a vacuum leak, just in case something around there is awry. Like @baldilocks said, if the EGR was stuck open, the idle would be all wonky. Simply disabling the EGR gets rid of the majority of the heat near the harness, the rest is likely heat soak travelling through all the metal in the area. If I remember right, although I should probably re-read the FSM, the exhaust does not get past the EGR (like the drawing in post#4) and up to the modulator unless the EGR opens. That opening is based on a variety of things, engine load, coolent temp, speed, etc. My kit stops it from opening. And yeah....don't overthink this.

First off, I feel like this kit is a god send. So thank you

2nd, can you talk about what mechanism in your kit specifically disables the EGR? I also messaged you the same question if you'd rather discuss there. But I'd like to understand exactly what happens. I was under the impression that the plug just prevents the error code by pretending to be the temp sensor, and the bbs were needed to block hoses ( and this is what disables the EGR). I'm elated to know that the BBs aren't even needed, but still would appreciate the knowledge, if you'd be so kind. .

 

[LC4LIFE]

I appreciate the interest and desire to learn, but I am not going to rehash the whole thing here in a new thread. The mechanics of how it works is in the multiple other threads related to the kit and/or disabling the EGR. If you want the exact details of how it interacts with the ECM, get out the FSM, it's all in there too.

Start with the link in my signature if you want to visit the EGR rabbit hole and learn.

 

[desertwampa]

I appreciate the interest and desire to learn, but I am not going to rehash the whole thing here in a new thread. The mechanics of how it works is in the multiple other threads related to the kit and/or disabling the EGR. If you want the exact details of how it interacts with the ECM, get out the FSM, it's all in there too.

Start with the link in my signature if you want to visit the EGR rabbit hole and learn.

Great...looking at the threads now and it inspires even more questions about readiness. Instead of just answering the question, you're gonna force me to trudge through pages of data to find an answer that may be even less clear than what I asked. Awesome!

 

[Fosters]

I have also wondered if you can buy one of Wits End's keychains that fits the EGR opening, and then install the keychain "under" the EGR pipe. That way the hot gases are blocked at the port, but the required equipment remains present for inspection. But you may not be able to do that without the head removed.

And one more thing-- I believe I read that someone blocked off the inlet to the EGR valve with a quarter or something placed between the EGR pipe and the EGR valve). That would seem likely to work. But I don't know for sure if it would or if it has ever been done.

I did exactly this…works great and no gases gettin into the head and no CEL

 

[desertwampa]

I did exactly this…works great and no gases gettin into the head and no CEL

with the keychain?

 

[Fosters]

with the keychain?

Yessir

 

[desertwampa]

So this picture here (stolen from another thread) is the one thing I need to do to stop the EGR from opening ya? Basically the 2 hoses coming off of throttle body get connected together by one single hose? Essentially if my research is right it, this is the vacuum source that causes the EGR to open. Remove these and the EGR will never open....right?

 

[ZackR]

So this picture here (stolen from another thread) is the one thing I need to do to stop the EGR from opening ya? Basically the 2 hoses coming off of throttle body get connected together by one single hose? Essentially if my research is right it, this is the vacuum source that causes the EGR to open. Remove these and the EGR will never open....right?

View attachment 3569425

Add the resistor to the temp sensor (on 95+, 93-95 just need the sensor shorted) and loop these vacuum hoses to disable EGR, correct.

 

[Marvelicious]

Add the resistor to the temp sensor (on 95+, 93-95 just need the sensor shorted) and loop these vacuum hoses to disable EGR, correct.

That's what I did on my 96. Been working fine for... months-ish. You could loop them or plug them with vacuum hose caps. I looped them because I didn't have to go in the garage and figure out where I stashed that vacuum cap assortment.