Diagnosing the EGR Valve | 1993 FZJ

[awlandhide]

Ok…sorry to open another EGR topic, but I can’t seem to find the answer to what I am looking for. I am trying to diagnose a rough idle on my ‘93 FZJ and suspect the EGR valve. Before I purchase and install a new EGR Valve, I first swapped out the vacuum modulator hoping that would do it, but no go. Then I removed all the vacuum lines to clean them out. When I removed the line shown in the picture, I noticed that there was some crud in there. I poked a small wire/paper clip in the nipple, and I can seem to get it in more than a 1/4 inch.

Question: Does that mean that it is clogged, or is that about all I should be able to reach and it is supposed to be blocked? Also, without a vacuum tester (I know I could get one off Amazon), are there any other quick tricks to help isolate the problem?

Thanks for your time.

 

[LC4LIFE]

If you mean "can't" when you said this " I poked a small wire/paper clip in the nipple, and I can seem to get it in more than a 1/4 inch." then yes, that is likely the issue. Very common port to get clogged. I usually use welding wire or something a little more flexible than a paperclip but it should go all the way through that port, I think its at least an inch to get through it.

Some have success blowing carb cleaner, etc through that port too.

 

[CharlieS]

Yes, it should be an open passage. A small twist drill and some solvent is an effective way to clean that passage out. Keep in mind it is a sort of passthrough, and if you don't unplug the vacuum line on the underside, you're just pushing gunk into it.

 

[BTLSHP]

I do not want to pour cold water over your success in finding a legitimate issue, but before you grind that carbon to fine dust, think about where it goes afterwards.... I guess if it works for a time you hav found something. I fought this error for quite some time until @Malleus encouraged me to be more systematic about things. I end up with several issues:

- Pile of carbon on the Temp sensor
- Cake passages in IM
- Pintle shaft gummed up in EGR
- Ultimately it was the VSV - resistance was fine, solenoid would fire, but over the course of 30 seconds the vacuum would leak own.

This one was frustrating and several times I thought I was done only to have it come back. I am having a bit of th same now with CEL 25/26

 

[Kabanstva]

Ok…sorry to open another EGR topic, but I can’t seem to find the answer to what I am looking for. I am trying to diagnose a rough idle on my ‘93 FZJ and suspect the EGR valve. Before I purchase and install a new EGR Valve, I first swapped out the vacuum modulator hoping that would do it, but no go. Then I removed all the vacuum lines to clean them out. When I removed the line shown in the picture, I noticed that there was some crud in there. I poked a small wire/paper clip in the nipple, and I can seem to get it in more than a 1/4 inch.

Question: Does that mean that it is clogged, or is that about all I should be able to reach and it is supposed to be blocked? Also, without a vacuum tester (I know I could get one off Amazon), are there any other quick tricks to help isolate the problem?

Thanks for your time.

View attachment 3838602

I hate to get off topic but what kind of clamps are those on the heater hoses? My s*** is all leaking including the heater control valve.

 

[BTLSHP]

I hate to get off topic but what kind of clamps are those on the heater hoses? My s*** is all leaking including the heater control valve.

Those look to be breeze constant tension clamps. They are good, it as long as you are using using Toyota hose sections, their spring clamps are perfect

 

[awlandhide]

@LC4LIFE & @CharlieS Thanks so much for the feedback. I will have a go at trying to clean it out.

@BTLSHP Thanks for “pouring” so real on this thread too! I know that I may be in for a long road on this one….nice to hear what you ended up finding. And yes, you are correct, those are Breeze clamps (@Kabanstva ). I did my PHH, new heater control valve, and rear heat delete….new hoses all around.

 

[CharlieS]

Also, I had good luck with Berryman B-12 Chemtool as a solvent for gunk in the EGR and intake area

 

[BTLSHP]

@LC4LIFE & @CharlieS Thanks so much for the feedback. I will have a go at trying to clean it out.

@BTLSHP Thanks for “pouring” so real on this thread too! I know that I may be in for a long road on this one….nice to hear what you ended up finding. And yes, you are correct, those are Breeze clamps (@Kabanstva ). I did my PHH, new heater control valve, and rear heat delete….new hoses all around.

This began as a project to get my father's 80 Series "cleaned up" for his granddaughter. Then the harmonic balancer nearly separated, then I noticed the PHH was bulged and we took it to our mechanic for a less than satisfactory result, finally the CEL (no emissions here, but CO has emissions test). Finally, we had a fuel line spraying all over....

So, we have one all new rubber hoses and lines, brake calipers, e-bake, rear hubs, front end to be one. Interior is last on the list.

I have pretty limited experience so I sponge off this site with a lot of gratitude for the people who take the time to teach.

 

[davedave]

Ok…sorry to open another EGR topic, but I can’t seem to find the answer to what I am looking for. I am trying to diagnose a rough idle on my ‘93 FZJ and suspect the EGR valve. Before I purchase and install a new EGR Valve, I first swapped out the vacuum modulator hoping that would do it, but no go. Then I removed all the vacuum lines to clean them out. When I removed the line shown in the picture, I noticed that there was some crud in there. I poked a small wire/paper clip in the nipple, and I can seem to get it in more than a 1/4 inch.

Question: Does that mean that it is clogged, or is that about all I should be able to reach and it is supposed to be blocked? Also, without a vacuum tester (I know I could get one off Amazon), are there any other quick tricks to help isolate the problem?

Thanks for your time.

View attachment 3838602

It’s very likely that the main EGR passageway inside the intake manifold (from where EGR is bolted on through to the middle where the throttle body bolts on) is also clogged. There’s a thread somewhere where a guy points out each of the main passages that get clogged. It’s not too bad to clean it out once TB and EGR are unbolted.

 

[BTLSHP]

That and ensuring the pintle shaft on the EGR valve moves freely are almost the starting point. The modulator is an easy check. Getting to the VSV is a pain, but if you figure out the wiring you can test fire it and check the resistance from the connector at the front of the throttle body. What you can’t do easily it test whether it holds a vacuum and, of course, that was my issue.