egr bypass
#1
egr bypass
My egr valve has finially crapped out for good and I am considering a bypass. I remember seeing a post here somewhere where someone had done an egr bypass by plugging the two vacume hoses and the hose that comes from the exhaust and into the bottom of the valve then replacing the hose that goes from the side of the egr valve into the engine with a filter cap thing. Anyone have any suggestions or remember where that post is? Anything elsi I should do while I have the egr out?
Thanks
Thanks
#2
How do you know the EGR is bad? (Just curious)
If you haven't already done so, one way to check is the following. With the engine cold, look at your EGR valve and you will notice the bottom has some cutout pieces with a diaphram visible through these holes. Simply apply vacuum to the the EGR valve (e.g. using a pump or even just your mouth and the EGR vac hose) and see if the diaphram goes up when vacuum is applied and down when the vacuum is released. If it does your EGR valve is fine.
As for capping the vac line into the EGR valve (from the EGR modulator), I have tried this and the check engine light came on within 20 miles of driving (95 4runner, 3.0L). However, I had noticeably more power for those 20 miles. So, what I ended up doing was resintalling the hose and then placing a homemade clamp on it. I clamped the hose down so the EGR valve still gets vacuum, just not as much. I did this, though, because I believe my EGR is opening up too much too soon (i.e. at too low RPM). Restricting the vac line is an easy way of adjusting when the EGR opens up. However, if your EGR valve truly is bad, you will need to get a new one. Capping or restricting the vac lines won't do anything if your EGR is permanently stuck (open or close)
If you haven't already done so, one way to check is the following. With the engine cold, look at your EGR valve and you will notice the bottom has some cutout pieces with a diaphram visible through these holes. Simply apply vacuum to the the EGR valve (e.g. using a pump or even just your mouth and the EGR vac hose) and see if the diaphram goes up when vacuum is applied and down when the vacuum is released. If it does your EGR valve is fine.
As for capping the vac line into the EGR valve (from the EGR modulator), I have tried this and the check engine light came on within 20 miles of driving (95 4runner, 3.0L). However, I had noticeably more power for those 20 miles. So, what I ended up doing was resintalling the hose and then placing a homemade clamp on it. I clamped the hose down so the EGR valve still gets vacuum, just not as much. I did this, though, because I believe my EGR is opening up too much too soon (i.e. at too low RPM). Restricting the vac line is an easy way of adjusting when the EGR opens up. However, if your EGR valve truly is bad, you will need to get a new one. Capping or restricting the vac lines won't do anything if your EGR is permanently stuck (open or close)
#3
maybe not faulty EGR
szf2 thanks for the response,
BTW - I have a 95 3.0 rebuilt engine with about 20,000miles.
Well I looked into the EGR test that you suggested, but couldn't see the diaphram through the holes on the bottom while the egr was still installed. So I splurged on a Chiltons and their test was almost the same but said to apply vacume to the EGR valve while the engine is cold, if the EGR is ok vaccume should produce rough idle, and it did.
The reason I origionaly suspected a faulty EGR was the truck began to have an ocasional hickup running at high rpms like on the freeway. There would be a momentary hesitation accompanied by the check engine light just for a second then normal running and no light. Then I had normal running but the check engine light was always on. I pulled the code and it said it was the EGR. I unhooked the EGR and cleaned with carborator cleaner, reset ECU and after a bit, no light good running, mostly. So Friday I have been driving all day with good running. I get home and the truck sits for 20 minutes. Then I want to go to the video store, I turn it over and it dies, turn it over again and give it some gas and I have a very rough idle. I give it more gas and it revs but shakily. There is also a hissing noise from around the air intake which is normaly there but now its loud and sporadic. Also the engine is normaly a bit clicky but there is a loud clicking toward the rear pasanger side of the engine block. I call a mechanic and he very graciously talks me through the problem. From the symptoms he thinks it's the EGR, he says unhook the vac lines and the line out to the engine and if EGR is faulty the engine should run better with it unhooked, and it dose. But now with the Chiltons test comming back ok, I just don't know. Sorry about the long post, but I wanted to give all the background.
Thanks
BTW - I have a 95 3.0 rebuilt engine with about 20,000miles.
Well I looked into the EGR test that you suggested, but couldn't see the diaphram through the holes on the bottom while the egr was still installed. So I splurged on a Chiltons and their test was almost the same but said to apply vacume to the EGR valve while the engine is cold, if the EGR is ok vaccume should produce rough idle, and it did.
The reason I origionaly suspected a faulty EGR was the truck began to have an ocasional hickup running at high rpms like on the freeway. There would be a momentary hesitation accompanied by the check engine light just for a second then normal running and no light. Then I had normal running but the check engine light was always on. I pulled the code and it said it was the EGR. I unhooked the EGR and cleaned with carborator cleaner, reset ECU and after a bit, no light good running, mostly. So Friday I have been driving all day with good running. I get home and the truck sits for 20 minutes. Then I want to go to the video store, I turn it over and it dies, turn it over again and give it some gas and I have a very rough idle. I give it more gas and it revs but shakily. There is also a hissing noise from around the air intake which is normaly there but now its loud and sporadic. Also the engine is normaly a bit clicky but there is a loud clicking toward the rear pasanger side of the engine block. I call a mechanic and he very graciously talks me through the problem. From the symptoms he thinks it's the EGR, he says unhook the vac lines and the line out to the engine and if EGR is faulty the engine should run better with it unhooked, and it dose. But now with the Chiltons test comming back ok, I just don't know. Sorry about the long post, but I wanted to give all the background.
Thanks
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