22re Misfiring

[strykersd]

Ok, I've just about had it with my 86 4runner, it's been misfiring on cylinder 2 which makes it shake at idle and stops making power at 3000RPMs since the day I bought it two years ago. When I first bought it, it had a check engine light for the coolant temp sensor and the O2 sensor and was having charging problems. I replace both sensors and the alternator and it fixed both of those issues but not the misfire.

In the past two years I have...
-gave it a tune up (plugs, wires, cap and rotor)
-replaced the MAF Sensor
-sent my injectors to witchhunter to have them cleaned and flow tested
-replaced the fuel filter
-blew up the first engine and replaced it with a used 22re
-New catalytic converter

But nothing seemed to help. I've also taken it to two shops, the first told me nothing and managed to break my TPS sensor. The second thought it was a bad injector, but after swapping the injectors in cylinder 1 and 2, nothing changed.

So what I know...
-the second shop said the ECU checked out
-compression is good
-no CEL
-after swapping out my MAF sensor for another I ruled that out
-checking the plug wires with a timing light, all 4 get spark
-the second shop checked cylinder 2's injectors plug and that has voltage
-engine compression is good, but I ruled out a mechanical problem with the engine since this new engine has the same symptoms the last one did
-there's nothing blocking the intake runner for cylinder 2
-I've taken in on 200 mile drives. It always starts and runs, but never runs well
-won't pass California's emissions


Anyone have any ideas? I've dumped hundreds of dollars into trying to find this problem with no luck. I'm getting to the point where I'm somewhere between just selling it or swapping in a Supra 6 cylinder. Thanks for any help!

[corax]

check out this thread (http://forum.ih8mud.com/79-95-toyota-truck-tech/311436-22re-injector-problem-i-had.html) - might be an electrical problem with the injector

[strykersd]

Thanks Keith! I have the whole harness out and intake manifold off the engine so I'll pull it apart and check them out.

[strykersd]

After pulling the harness apart and playing with my multimeter I concluded that the all the connectors are intact. When I re-install the harness and intake manifold I'll see if swapping plugs between cylinder 2 and 4 will move the misfire to cylinder 4 since those two injectors fire together. Back to the never ending drawing board...

[corax]

This will give you an idea of each cylinder's volumetric efficiency - basically checking how well the engine breathes and verifying each cylinder is equal. If you find a problem with this test, you are likely looking at a valvetrain problem (cam / valve sealing)


HOW TO PERFORM A RUNNING COMPRESSION TEST

1. Start with a normal ("static") compression test. To eliminate rings, valves, holes in pistons, that sort of things. A normal cylinder balance test is also helpful (so you know which, if any, cylinder is presenting a problem). Engine should be warm.

2. Put all spark plugs but one back in. Ground that plug wire to prevent module damage. Disconnect that injector on a port fuel system.

3. Put your compression tester into the empty hole. The test can be done without a Shrader valve, but most people recommended leaving the valve in the gauge and "burping" the gauge every 5-6 "puffs".

4. Start the engine and take a reading. Write it down

5. Now goose the throttle for a "snap acceleration" reading. Reading should rise. Write it down NOTE: Don't use the gas pedal for this snap acceleration. The idea is to manually open then close throttle as fast as possible while without speeding up the engine. This forces the engine to take a "gulp" of air.

6. Now write down your readings for at least the bad cylinder (if there is a single bad cylinder) and maybe 2-3 good ones. Make a chart like this: CYL STATIC COMPR IDLE -RUNNING COMPR - SNAP Cyl 1 150 75 125 Cyl 2 175 80 130 Cyl 3 160 75 120 Cyl 4 160 80 125

7. ANALYSIS: Running compression at idle should be 50-75 psi (about half cranking compression). Snap throttle compression should be about 80% of cranking compression.

EXAMPLE 1 - RESTRICTED INTAKE CYL STATIC COMPR IDLE -RUNNING COMPR - SNAP Cyl 1 150 75 80 If Snap reading is low (much less than 80% cranking compression), look for restricted intake air- severely carboned intake valve, worn lobe on cam, rocker problem. Comparing measurements between cylinders is important.

EXAMPLE 2 - RESTRICTED EXHAUST CYL STATIC COMPR IDLE -RUNNING COMPR - SNAP Cyl 1 150 75 180 If snap measurements are significantly higher than 80% of cranking measurements, look for restricted exhaust on that cylinder-such as worn exhaust cam lobe, or collapsed lifter. Or, if they are all high, look for a clogged cat converter.

WHAT IS GOING ON?

When you do a normal compression test, you are checking cylinder sealing, not cylinder breathing. When you check engine vacuum at the manifold, you are looking at the breathing of the entire engine, by checking vacuum at a common (plenum) source. You aren't testing a specific cylinder. This test looks at the breathing of an individual cylinder.

Say the engine is running at 18 inches vacuum. Atmospheric pressure is about 30 inches, so the difference (30 inches - 18 inches = 12 inches) is what the engine is sucking in. 12 inches mercury is equivalent to about 6 psi absolute air pressure. Compressed at an 8 to 1 ratio, you should get 6 x 8 = 48 psi pressure if all the air makes it into the cylinder and then gets pushed out. So your idle reading on running compression is about 50 psi.

When you snap the throttle, the manifold vacuum drops, so the absolute air pressure going into the cylinder increases.

In fact, you can do running compression tests at various constant manifold vacuum readings (by brake-torqueing the engine momentarily), and the running compression should roughly correspond to the manifold vacuum. For example, at 10 inches vacuum, engine should be breathing in about 10 psi air pressure, so you should see a running compression reading of about 80 psi (at 8 to 1 compression ratio).

If one cylinder reads low running compression compared to the rest it means that the air didn't make it in. If one cylinder reads high, the air didn't make it out (and the next pulse of air raised the pressure).

[CJM]

Good write up ^

[strykersd]

Thanks for the tip Keith. Once I clean out the intake manifold and throw it back on the engine I'll give it a try. One thing that caught my eye while pulling the harness apart was that the fuel injectors for cylinder 2 and 4 share a signal from the injector box. The last mechanic who worked on it said something about cylinder 4 not performing as well as 1 and 3, so I'm starting to wonder if it could be that injector box. I'll have to wait till I get this thing back together to see.

[strykersd]

No sure answer yet. I've spent the last few days cleaning out my intake manifold with a toilet bowl brush, a water bottle brush, a old tooth brush and a ton of engine degreaser. What I did discover was that one of my vacuum ports was clogged (the top left one) and while cleaning it out that chunk you see sitting on the intake manifold fell out...
http://members.cox.net/strykersd/intake%20manifold.jpg

[Seanz0rz]

what is that chunk made of? from the picture it looks like rubber, maybe a piece off an old intake tube?

[strykersd]

Nope, it's a solid piece of carbon buildup. Maybe 5/8" or 3/4" thick

[Seanz0rz]

woah! me thinks you had a very leaky PCV valve for a very long time. thats the only thing i can think of that would throw that much oil into the intake like that. either that or maybe an emission system component failed. either way, with that out of there your engine should run much better!!!

[strykersd]

I finally found the problem! Turns out it was the engine! While checking the valve lash I bumped into the exhaust valve springs and was able to compress the valve spring with my fingers. Turns out the exhaust valves on cylinder 2 and 4 were bad, 2 more so then 4 though. It was so bad that cylinder 2 never saw any compression when the engine was running. I guess compression tests won't tell you everything about an engine, at the 100RPMs the starter turns the engine over at the valve spring is fine but at idle it just couldn't keep up.

Anyone have any extra valve springs for a 22re laying around? Or know any place I could buy them at? I'm not finding them at the local autozone or kragen and engnbldr only sells sets.

Now what to do about the shop I paid $600 to for this engine...

[corax]

This will give you an idea of each cylinder's volumetric efficiency - basically checking how well the engine breathes and verifying each cylinder is equal. If you find a problem with this test, you are likely looking at a valvetrain problem (cam / valve sealing)


For valve springs, there are a ton of u-pull-it/pick-n-pull type junkyards around SoCal, go to one of them with some tools and go to town. With all the cash-for-clunker cars getting dropped off, there are a ton of treasures to be found. Here&#39;s one -> http://www.upicksave.com/ <- I used to know of a bunch of others, but can&#39;t remember the names right now. Ontario, Sun Valley, maybe Fontana (?) - might be some down your area as well.

[strykersd]

It's hard to find 22re's in junkyards around here. Anyone have access to the toyota parts catalog? I found a 22rte and was wondering if it uses the same valve springs

[Scuba]

Toyodiy.com for part numbers and such..

[wifesaysimadumbass]

holy crap that was a good find i was going to suggest swapping ecus with someone else but looks like you found it

[strykersd]

Yeah it was dumb luck I guess. I got everything up and running again, but it still doesn't make power above 3000RPMs. I'm thinking it might be the fuel pump, I need to get a gauge on it and find out.

No matter how good of a deal I get on a car, I doubt I'll ever buy a 300,000 mile vehicle that doesn't run right ever again...

[heavymetalviking]

I'm so glad I found this thread. My 22RE is having close to the exact same symptons, misfiring at idle and power kicking in hard at about 3500-4000 RPMs. I've also run down the list of possible problems, cap/rotor, sparks, wires, injectors, coil, mass air flow, alternator... the only difference is mine seems to only do it when raining or with low atmospheric pressure. On a dry day it'll run fine. Also I noticed my #2 spark was getting lots of deposits on the end and causing an even worse misfire. I cleaned out my exhaust manifold and intake manifold pretty good a couple summers ago. Any further insight on this problem would be much appreciated.