zombie_stomp

Thanks, I'm glad to know of another possibility. I believe I have the lines that open the EGR plugged because when I was changing vac. lines, I accidentally broke the line nipple off since it is brittle plastic and stuck on very tight.

I ran to Durham today and it got started with the problem right around the same place in my drive where it usually does, and after a few stops at stores it did finally stop the problematic behavior the rest of the way home and after another stop at the library. It usually does it hot, so I'm not sure if there's a way for the diaphragm of the EGR to open itself, but I will add tapping on it to my to-try list, as well as possibly opening it up and looking inside.

msane99

is there a catalytic converter on it? won't they exhibit different behaviors at various temps? by default egr would be closed so no vacuum line on egr = closed egr. unless all gooed up.

zombie_stomp

It does have a catalytic converter, an aftermarket one at that, with no o2 sensor attached, and the 02 sensor cut!

I'm trying to make sense of how that relates to the EGR being affected. When I disconnected those lines after I broke the line input, it didn't seem to affect how it was running.

When the problem happens, the exhaust smells richer. Hope that's a clue of some kind.

zombie_stomp

The problem has not come back tonight. It was there during my short trip/ sight seeing/ errand and eventually subsided.

I started the car and sat in it a good little while and went to the store. It idled fine, albeit a bit too rich at idle, and the main problem did not come back tonight. Got back from the short trip to the store fully heated up and sat a while longer at idle. Still no problem. I wonder how many people alive today are toyota nerd enough to know and care how the emissions systems work, and especially that little emissions control computer. Mine lacks any input from an o2 sensor.

I don't mean to water down the thread with conjecture, but it's a really cryptic problem.

g3bill2

No one would ever call me a nerd but a few years ago I followed each instruction in shop manual for the emissions about the switches and hoses to be sure it was all working properly, when done it was, but found it was a faulty Distributor advance diaphrams and after rebuilding it pasted Smog since, fingers crossed for next year...

ps; I repaired those vacuum plastc tit things with epoxy-gel and works well, but really needs to dry for 24-48 hours without strain.


egr, how it works ; http://www.agcoauto.com/content/news/p2_articleid/207
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msane99

Newer cars revert to a default rich setting when emission system is damaged. I have had coolant sensors cause this, bat O2 sensors, just about anything that causes a check engine light on ODB2 will cause the engine to limp @ these rich/limping settings till fixed.

Like you said, not sure how much that little emission box is actually doing. I am not sure where the technology was in 82, but emission system could be your problem. Are you in an area that requires emissions on such an old truck? I live in Georgia, and we have emissions but only in heavily populated counties. If you could get away with desmoging it?

how hard to put a bung on the exhaust pipe and add o2 sensor back into the mix?

I hate problems like this because you can spend a fortune and never get it right. dang gremlins!

g3bill2

I'm pretty sure the one temperature sensor that bolts to Catalitic coverter won't input to computer unless the cat overheats and if it does would turn off the EGR to keep motor from overheating.

zombie_stomp

Bill, I think you're right. It might affect CA models more because as I was reading last night, the air pump ("smog pump") injects more air into the exhaust to cool the cat or something. Yes, it's a "temperature sensor" at the cat, not an o2 sensor as I originally thought.

In good news, since yesterday on my way back from my usual weekend day cruise to Durham and back, after it did the rough running/ stalling on low throttle/idle thing on the way there, and stopped, it has not done it since then.

So if the EGR is a system that turns on and off frequently via the EGR valve, it is a prime suspect for the bad condition in question. Sometimes driving over bumpy areas in the road and different inclines as well as heat cycling seemed to influence it.

Today, it had the problem for about half a block after one of my errand spots in Durham. I thought, "here we go again....", but it stopped and idled fine by the time I reached the next stoplight.

Cleaning out the EGR system is next on my list this coming week. Plus I have a used EGR and complete emissions system rat's nest coming in the mail mid-week from Jrheingans. It will be tricky if I have to remove the little exhaust pipes, and I think the EGR is kind of hard to get to. One trick I know of is to heat stuff up (run engine in my case to get manifold and studs hot) and then put on some parrafin wax and it is supposed to melt and draw the wax into the threads and work like penetrating oil. In this case it's a good idea since penetrating oils are usually thin and would burn off under the heat if I were to pre-soak the threads like people do with suspension components, etc.

Wish me luck!

zombie_stomp

I would only desmog if I absolutely could not find the problem. NC where I live now will only be emission testing my year for a couple more years, but I will probably be in Oregon by then, and living in Portland. Trying to pass their emissions would probably be pretty challenging with a de-smogged truck, so I'm trying to be as meticulous in the diagnosis and fixing of the original system as possible. A lot of young hot rodder kids usually desmog as soon as something doesn't go their way, and I'm trying to avoid throwing parts at it and throwing the baby out with the bathwater. I am also a fan of actually keeping my truck low-emissions as possible. I'm fine with the amount of power it has.

g3bill2

BTW the o2 sensor is bolted into the exhaust header which i'm kinda sure will effect the computer in some way, think to rich or lean mix i think? but the one into Cat won't matter as mine is cut (idiot muffler man. I found a temp probe with a short wire and past smog even though it wasn't wired in to computer.) and no issues in 4 years?
Were you talking of the small tube that runs around the back of motor, guess its from egr to exhaust on manafold side. I had to remove mine years ago as it was clogged with carbon sludge cra% and cracked making some noise. I welded it with a patch and put it back after cleaning and paint, has been ok for 8+ years now. Just wondering if yours could be clogged a bit? don't know the effects of being restricted?

zombie_stomp

The problem finally did come back after a record-setting problem-free week.

The week included long and short drives in all heat ranges.

I was getting a new belt for the truck and came out and the idle problem happened. I got out and a few light taps with a screwdriver handle and it fired right back up. I drove a few miles and decided to stop and eat because it came back again. This time it seems like no amount of tapping will make it idle normally. But that first time it seemed like EGR valve responded so I feel I may be on to something. I'm not sure what I'll find when I get into the EGR system, but I'll be sure to have my used replacement on hand before I check into it.

It did fire up and run normally after cooling down. EGR system cleaning and valve replacement #1 on the list.

treeman89

I have a question regarding my recent compression test on my 1998 4 runner 2.7 litre.
Is this considered good? What is considered Factory Compression?

CYLINDER 1-210, CYLINDER 2-210, CYLINDER 3-200, CYLINDER 4-200 PSI

treeman89

Thank you!

msane99

Treeman89 may wanna open a new thread on this. This board is for trucks older than 1985. factory for 87 22re 2.4 litre is 142-171. the 200 seems a little high but maybe that is normal for 1998. as long as our engine is within 14lbs of the other cylinders it is good.

example would be:

152 155 150 160 would equal a good compression test for 22re.

so in my opinion pressure seems high but your consistencies are good.

zombie_stomp

Now that the cold starting issue is out of the way, and the running/ no idle is basically gone except for the rare chance and is narrowed down to EGR issues, it may be down to the ticking/ clacking issue I have. Which I myself may want to start a separate thread on.

It is an ever present ticking. Then there is a more squishy squeaky sound that is more "cushy" sounding, mostly on deceleration, but also kind of "tacky" and seems to match with the ever present tack. Sometimes they both go away, like when I've got the idle at its smoothest and lowest, or say, uphill in 4th gear under major load.

I think it's the timing chain area of the engine now after a lot of troubleshooting and other tuning including:

-adjusted the valves properly; when hot and to the factory specs. As advised by the manual I did also make sure the cam hold down journal bolts were tight and one of them moved under tightening and I torqued it down. Not too bad, just slight.

-replaced the belt. One member here suggested belts and pulleys can go slack or rhythmic belt squeaks can sound like knock. I got a top grade Dayco Top Cog belt and installed it snugly, same sound persisted.

-I disconnected each cylinder, one at a time and ran the engine. Since the engine was out of it's usual rhythm, the sound was more faint, but still there each time I disconnected just one of the spark plugs. That was nerve racking since the possibility of having rod knock is a big deal. So I was glad the sound was still there.

While I was having running issues while I was simultaneously trying to diagnose this sound, it made things a little harder to figure out.

I also have a tiny pinhole of a leak in my manifold. A very small slit with white-gray carbon around it is visible. While I know I could very easily grind some material around it away and stick weld it using a special cast iron arc welding rod, I don't suspect this to be the tick problem. I think my ears are better trained than that after 15 years of conscientious wrenching on every single one of my motor vehicles.

I'm pretty sure, if the tests and maintenance have been correct, that at 133,000 miles, some of which were kind of abusive miles by previous owners, that I have a timing chain set in need of replacement. I have seen receipts of 13X,XXX 2_R series engines having their timing chains replaced.

Not jumping to conclusions yet, just keeping my finger on the Engrbldr.com site and considering doing what I did with my '83 (replacing the timing kit) while trying to remember what of my friend's tools I had to borrow that I don't own in my current setup. And considering the purchase of a mechanic's stethoscope.