[barkbark]

Haynes isn't much use in this department, and a search comes up empty.

There is one hose that is capped(although, I'm not sure what it's for, a mechanic I took it to said he had no idea what it was for, it is attached to the back of the engine somewhere). There is also this issue with the coolant pipes,as it looks like someone clamped one of the pipes, but I'm not sure if it cuts off coolant or not.

My engine is not overheating, as far as I can tell. But there is a rough idle, which I think is due to a clogged EGR valve(vacuum pump test seemed to confirm it's clogged), but I could be wrong.

 

[Stillrunning]

There is also this issue with the coolant pipes,as it looks like someone clamped one of the pipes, but I'm not sure if it cuts off coolant or not.

Doesn't look like it's crushed much. I think those pipe go to the heater core, which would not affect engine heat, just cabin heat.

But there is a rough idle, which I think is due to a clogged EGR valve(vacuum pump test seemed to confirm it's clogged), but I could be wrong.

If you applied vacuum to open the EGR while idling and the engine did not stall then the EGR is clogged/non-functional.

 

[barkbark]

If you applied vacuum to open the EGR while idling and the engine did not stall then the EGR is clogged/non-functional.

I got a vacuum pump from autozone, and attached it to the opening on the top of the EGR, gave it a few pumps, and the engine didn't skip a beat.

 

[Stillrunning]

So the EGR could just be blocked with soot/carbon, which can be cleaned, but it's best to remove it to clean it. I've used spray oven cleaner but beware of fumes, so do it outside. Previous owner may also have blocked it off with a gasket. You'll also want to clean the pipe coming from the exhaust. The big nut needs a 15/16" crows foot wrench.

A non functioning EGR should have no effect on idle as it's closed anyway when on idle. What idle RPMs are you getting?

 

[barkbark]

Idle RPM's is less than 1500 and decreases to <800. When it's <800 there is vibrating, sometimes more sometimes less, the warmer the engine the more vibrating(generally), but more vibrating when it's in reverse and when braking from 50 miles an hour to stop at a red light, similarly when it's <800 and going 50-60 or so there's shaking or vibrating. It's not like an earthquake or anything, I used starting fluid and it seemed to help, but didn't quite fix it.

On a related note, there was a wrong air filter installed, which I replaced. Which is probably part of the reason the air intake manifold is so dirty. If you open the throttle body you can see dirt or carbon or whatever it is.

The engine mounts were rusted out, and I had them replaced, but the stupid mechanic (who also put 5/40 oil in) only replaced the front and the torque mount, and not the rear and the transmission mount. I called a week later, but conveniently they were closed due to corona virus. I had a lot more shaking before this was done. The rear mount seems fine ,but I can't seem to get a view of the transmission mount.

There's also the fact that my exhaust pipe had to be patched up via welding. It could be clogged, but haven't gotten around to testing it. I'll try and do it today if I can find the time.

I tried to take off the EGR, but I got the two top screws off fine, but the bottom two just won't budge. I've tried multiple tools, multiple lubricants. My 3/8 wrench won't fit, I got a 1/4 but that just wouldn't budge. I have a wrench, but that seemed to start to strip the bolt so I stopped using it. I could get a flare nut wrench? But I'm not sure that would work better than my 1/4 socket wrench. The only other ideas would be a propane torch or a dremel, a full size drill has no hope of fitting back there.

hmm... the post was longer than I wanted, but w/e.

 

[Stillrunning]

What's the history of the engine? Are you first owner?

Normal hot idle rpm should be about 650 - 750. Being a Gen4 you should have OBDII, so a scanner may shed some light on fuel trims, if no codes then they're probably not that bad. If the RPMs drop when in reverse or when braking then possibly the IAC could be at fault, and low RPMs will show more vibration. What are the RPMs when braking/reverse? Cleaning IAC might help.

I'd also clean the throttle body with spray and toothbrush and cloth.

It's possible the previous owner removed the balance shaft.

I don't know fully how the Gen4 EGR is bolted to the intake manifold. Mine only has two bolts plus the large nut securing the exhaust pipe.

 

[barkbark]

It's been owned by six people.

I have a OBDII scanner, and there are no codes. The app I have provides a good deal of information from the ECU, but I wouldn't know what to look for.

There's two nuts securing the EGR to the intake manifold, those I can remove. But there are two bolts securing it to the pipe, which I assume comes from the exhaust. It's difficult to see where anything goes behind the engine. But it is a metal pipe, not a hose. These two bolts are near impossible to remove. The easiest way would be to get a dremel and destroy the EGR and replace it. I suppose another method might be to find out where that pipe goes, and disconnect it from the exhaust?

 

[Cosmofennema]

I suppose another method might be to find out where that pipe goes, and disconnect it from the exhaust?

That pipe goes to the head, and is secured by the large nut referred to in a previous post. You may find that there is a lot of room to work once the intake assembly is removed.
Too, carburettor cleaner works a treat to remove carbon.

 

[Stillrunning]

But there are two bolts securing it to the pipe, which I assume comes from the exhaust. It's difficult to see where anything goes behind the engine. But it is a metal pipe, not a hose. These two bolts are near impossible to remove.

That may be the way the Gen4 secures the pipe to the EGR instead of the big nut on my Gen3. Try soaking the bolts overnight with plenty of penetrating oil, then use a 6 point socket. When using penetrating oil it's important to tap, tap, tap with a hammer to vibrate the oil into the thread. If that doesn't work then heat might, but a propane torch might not be enough heat fast enough.

 

[barkbark]

Normal hot idle rpm should be about 650 - 750.

At operating temp, it's about 700, with an occasional spike to 900.

It's possible the previous owner removed the balance shaft.

You mean this thing:

How would it even be able to run at all without it?

 

[Stillrunning]

How would it even be able to run at all without it?

I don't know, but there have been discussions on this site about removing it. I think some believe they get more POWER!

Anyway, maybe do a compression check to see if cylinders are about even.

 

[BMR]

It adds rotating mass, so the engine will rev quicker without it. It’s there to reduce secondary imbalance vibrations inherent in a 4 cyl engine.

Some claim it a common source of problems, so they delete it, and plug the oil port feeding its bearings.

 

[barkbark]

Can you see if it's there by removing the valve cover? How would I be able to tell without removing the whole cylinder block?

I did do a compression test in another thread, it was like 180 190 200 200, or so, not in any particular order. The first time I did it without the throttle open, and it was 175 180 140 140.

 

[BMR]

Can you see if it's there by removing the valve cover? How would I be able to tell without removing the whole cylinder block?

It’s at the bottom end. So you’d see it if you removed the oil pan.

 

[barkbark]

Let's say someone did remove the balancer shaft, wouldn't it vibrate all the time? And not just specifically 800 or less RPM when the engine is at running temperature?

I removed the throttle body, and replaced the gasket, and did as good a job as I could cleaning out the intake manifold without removing it. I used brake cleaner this time, and that seemed to remove more crud. Although, it just all fell down into system, so I'm not sure if I made the problem worse or not. I sprayed it directly into the EGR valve from inside the manifold. So, it's not going to be anymore clean without removing it. It seems like there's less vibrating, but not really sure if that's just me wanting it to be solved.

Also, I did try again to remove the EGR with the throttle body removed, and I just couldn't budge the bolt. It's now stripped, unfortunately, I guess the lesson is to never use a 12 point on a rusty bolt. I couldn't even get at the bolt on the other side anyway. I could get my little 1/4th onto it, but there was no room to swing it. The only possible way to remove it, so far as I can tell is by undoing the pipe connected to the engine. But what size nut is that? Do they even make flare nut wrenches at 23/24mm? It appears to be a similar nut to what's on the bottom of the fuel filter, where's it's inbetween two male connectors.

 

[BMR]

Let's say someone did remove the balancer shaft, wouldn't it vibrate all the time? And not just specifically 800 or less RPM when the engine is at running temperature?

I don’t know, as I’ve never experienced it with and w/o the balancers. But running temps should have no effect.

 

[Cosmofennema]

I don’t know, as I’ve never experienced it with and w/o the balancers. But running temps should have no effect.

I have removed the assy on the rebuilt engine. Back to back you'll notice a bit more buzz. Nothing objectionable.

 

[barkbark]

View attachment 298740

So, the hose connects to the back of the cylinder head, above the fuel delivery pipe. What's supposed to be in that hole? I guess I should have made a picture more directly. Maybe tomorrow.

I found this:

Toyota Official 1994 (1992-1996) Mk3 Camry Repair Manual

www.turboninjas.com

Which has a lot of great information about gen3, but unfortunately I can't seem to find it for gen4.

Incidentally, I've been intermittently smelling a gas, exhaust, burnt oil/gas mixture. Sometimes one odor dominates, sometimes not. For instance, I started it up this morning and I stepped out of the car to grab something, and the area reaked of gas fumes. I was really surprised how bad it was. I never smelled it that bad before. I mean, it was a mixture, but the gas smell dominated heavily.

The cap on the fuel deliver pipe on the drivers side appears lose. I don't know if it's supposed to be that way or not.

 

[barkbark]

According to this, it appears to be something California forces on its hapless residents that isn't connected correctly.

 

[insightbrewery]

Mm, not so hapless. It feeds air to the air-assist injectors. Somebody correct me if I'm wrong but it's on pre-2000 5S-FEs.