erg valve and engine stalling

Put on an egr from my friend's 90. This was on my 87. The stupid engine stalls everynow and then with the egr connected. Will disconnecting it cause any damage to the 02 sensor, or is that the easiest way to go? (I don't care about emissions, got a 2 year exemption for being a student )

xjblaine said:

Put on an egr from my friend's 90. This was on my 87. The stupid engine stalls everynow and then with the egr connected. Will disconnecting it cause any damage to the 02 sensor, or is that the easiest way to go? (I don't care about emissions, got a 2 year exemption for being a student )

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You could also just disconnect the EGR Valve soloneid which is on the fender right behind the fuel pump resistor. Disco'd mine 6 months ago because of the stalling.

did you pop it open, an check the diaphram? a missing/torn diaphram will do that- I bypassed mine, looking back, it would have been easier to disconnect at the valve, but with the diaphram missing in action, it would probably bleed vacuum....an we need all that we can get.

I would not disconnect the solenoid, because it also controls fuel tank purge. Just disconnect and plug the line to the EGR instead. Or you can just crimp it off or tie it in a knot.

Of course I have to add the disclaimer that if you want to be a responsible citizen, you should fix your EGR. Your Jeep will probably not know the difference though. My 87 never did.

One of the ways the EGR valve can fail is that wear causes it to hang open intermittently. You can reach down under the diaphragm and wiggle it and it will usually snap shut. Make sure it's shut before you disarm it.

Matthew Currie said:

I would not disconnect the solenoid, because it also controls fuel tank purge. Just disconnect and plug the line to the EGR instead. Or you can just crimp it off or tie it in a knot.

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I just disco'd the vac line at the solenoid, and plugged up the hole in the solonoid. I didn't disco the wiring, so by what you are saying the solonoid is still working just not the valve, right :dunno:

I could be wrong, but I was always under the assumption the EGR solenoid, energized, deactivated the EGR valve. In other words default for the solenoid (not enrgized) was open. Unplugging the solenoid may, cause the EGR to perate at start up and other inapropiate times.
Probably be better off, disconnecting and plugging the vacum line to the EGR. Or better yet removing the EGR and making a solid gasket (Copper sheet), just in case the EGR is hung open a touch or the seat or rod is cruddy and holding the piston open some.
I´ve worked the rod for the EGR carefully with a pair of needle nose pliers. On occasion it seemed to seat that last few thousandths, tipping me off, it was sticky and/or not seating completely.

Matthew Currie said:

Of course I have to add the disclaimer that if you want to be a responsible citizen, you should fix your EGR.

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yeah, but there's that whole no money thing, and I thought I was fixing it. It did pass emissions in AZ though. I'll just leave it disco'ed

I had a bad idle problem once. It had that famous high idle issue at when I started the engine that I've been dealing with for about 4 years. But suddenly last year it also developed a lousy idle that would cause the engine to die if I took my foot off the gas. I took it to a mechanic last year and they couldn't diagnose it, even with the computer. The O2 sensor was bad so they replaced it. Then they disovered a big vacuum leak but couldn't find it. Then they said that they were calling other mechanics and even going to forums on the net to find answers. It got to the point where they took the timing chain cover off to make sure the chain didn't slip or something weird like that (they even busted a bolt off in the block and it took them 2-3 days to get it out :flamemad: ). When they got it all back to together it worked fine...really weird. For about 6 months in ran pretty good...

Then the high idle thing at start getting really worse (50-70%) so I took it to ANOTHER MECHANIC (figured the first one didn't know what he was doing). Diagnosis turned up nuthin. Everything looked good but they recommended an fuel system clean which helped for a few weeks.

My alternator went out last week at work and I had to have it towed to a THIRD MECHANIC. As soon as they fixed it the mechanic said he noticed that it sounded like it was missing. That damn idle problem suddenly came back and when I tried to drive it home it died when I came to a stop, just like before. He scratched his head and asked me to keep it overnight. I called him the next day and he said it was fixed. He plugged the vacuum tube that goes from the solenoid to the EGR with a ball bearing. He called it "ancient chinese secret". He's a bit of a weirdo...but smarter than the rest of them. He explained that's what was causing the "vacuum leak" and how it was causing the engine to run poorly...he said this problem wouldn't have shown up on any computer diagnostic test.

I live north of Denver and emissions tests are required in my county. I think he would have said something to me if he knew it wouldn't pass emissions...I guess I'll find out soon enough.

Not only did it stop the poor idle issue, it also stopped the high idle at start issue. In addition, the engine runs better than it has in years. :thumbup:

I am running no egr, and it runs just fine, this tech article is realy good, it is for blow by but it also winds up disconnecting your egr, the intake is not neccesary.
http://www.jeepxj.com/JeepXJ/oil blowby fix.htm

The egr block is a common problem/solution with these types- what happens, is the diaphram inside the EGR yoyo has ruptured- hence the engine will be sucking hot gas exhaust at idle, instead of half throttle and above. Its supposed to open at close to full throttle, but Ive yet to see that happen.
It basicly disrupts the flow of air and gas mixture-thats the best way to explain it I can think of. Ive always bypassed mine-Ive got no emmision problems here yet-no tests. But the jeeps Ive had have all run much better with the egr bypassed at the yoyo. I go one step further than a BB- I use a fish aquarium off/on air valve. Fits perfect inline.

The diaphram check is easy if you ever want to look at her. Just unplug the yoyo, take a flat head screwdriver and gently pry it apart. Inside, you`ll find the diaphram, and the spring...well, thats what you hope to find. If your jeep has a few years on it, you`ll probably find a ruptured diaphram, and a small pile of rust, which used to be a spring.

Suction from the engine pulls the spring, opens the egr so gas gets through the lower oriface, and pulls it back when at low rpm/idle so none gets by. No spring means some will always get by, ruptured diaphram means your pulling vac from the engine- that causes low vac signal...and we all know what that do.

my vac. line on my EGR has been discoed for two years now and no bad effects. I just unplugged the top vac. and plugged it with a screw.
DIG IT!

I am kind of woried about whether or not I will pass emisions, I have to pass it this week. Any bets????

not a chance-no bets from me.
but I`d say you got a 70/30 odd ratio, depending on how well maintained your engine is- fill her up with good oil, change out the cap/rotor/plugs and a new air filter, and its possible you might just squeak through. ive heard of a few makeing it at "the test" with a plugged egr, but theirs were top notch engines with no blowby and good compresson.

besides, it wont hurt anything but your wallet to find out, and most states give you a few chances-and even then theres "rules" that can help you out.

I`m not in an emmision county, so I cant help with "the rules" in your case...but theres been quotes and rumors posted on here before.

I used to have a funny smell, similar to gear lube, come into the cab from underneath somewhere when I had the window rolled down. Now it's gone, ever since I blocked that tube going to the EGR. I figured it was coming from the leaking fluids from underneath the jeep, up through the manual shift boot which is cracked.

I find it odd that in a dozen responses, EVERYONE is recommending the
bypass option... and nobody even THOUGHT to mention the cost or
availability of a replacement EGR valve!

EGR and PCV, and a few odd cracked vacuum lines here and there are
just a part of the "game" of driving an older vehicle! In many states,
fixing it CORRECTLY (per a VISUAL TAMPERING clause in the emissions
laws) is necessary.

Denlip some of us are not rich and cant afford to pay $100 for a new EGR (just a guess on price)
but if you can hell go for it. I dont have to worry about emissions so that is not a problem with me.
I find ways to do stuff cheap, easily, and effectively if that dont work I get out the sawzall. thats just my way.
That is all.