22re missing occasionally, failed smog

[SPANNERSPINNER]

So, I just bought a hoopty wagon in the form of an 87 4RUnner to drive while my FJ62 visits Tor Slinning's Land Cruiser Day Spa and Rehab Center. Trouble is she's missing and I'm failing smog with high HC because of it. Engine has 215k on the clock.

I've need reading through this and other forums and here is the situation.

How I know its missing:
Tail pipe smells like gas and occasionally you'll hear a miss at the pipe.
Engine runs rough occasionally and shakes like hell. It doesn't always misbehave, and sometimes are worse than others.
High HC at the smog shop. Something ain't burning and its enough to get past the cat.
If I barely touch the accelerator the engine wants to try and die

What has been done
Timing : check connector set and I'm at the marker for 12* BTDC.
Replaced sensor in exhaust manifold (did the blindly, was dumb)
Numerous vacuum hoses replaced with some silicon tubing I had intended to use on the Cruiser that needed a new purpose for being.
Seafomed the living s*** out of it. Ran the tank down to 1/4, poured a can into the tank, drove it like I stole it and refuled. Half a can of seafoam into the oil fill as well.
Seafomed the upper end through through the brake vacuum booster
Pulled cleaned and tested the cold start injector. It ain't stuck on, and it works with 12v applied.
New plugs
New wires
New rotor
New cap
Checked and verified spark at each cylinder
Verified resistance on the plug wires
Stuck a mechanics stethoscope against each injector and heard them ticking appropriately.
Did a compression check (180, 180, 150, 180). Redid the low one with a few ml of oil in the cyl and the number did not improve.

I need to do another oil change and get the seafoam out of the bottom end and I'm thinking I should pull the valve cover and check lash tomorrow. After that... Pull the injectors and have them tested? I don't know where to go after. Maybe check the timing chain, cam, and main shaft are all aligned while in have the valve cover off? I'm kinda stuck after the lash check.

What am I missing? I seem to have spark, I have air, and I have fuel if I can smell it at the tail pipe. I though I had too much fuel but the injectors tick and the cold start injector isn't stuck...

Smog numbers
15 mph:
1599rpm
%CO2 meas - 8.2
%O meas - 8.7
PPM HC max -131
PPM HC ave - 53
PPM HC meas - 177
%CO max - 0.61
%CO ave 0.08
%CO meas 0.41
PPM NO MAX - 1185
PPM NO AVE - 392
PPM NO MEAS - 638
25mph
2455 RPM
%CO2 14.1
%O2 0.5
HC PPM max 103
HC PPM ave 40
HC PPM meas 136
% CO max 0.77
%CO ave 0.10
%CO meas 0.41
NO PPM MAX 1120
NO PPM AVE 383
NO PPM MEAS 937

What the hell do I do next?

 

[Mudder]

I don't know much about smog but have you bothered checking for engine codes? Tps might be bad or something could be a throwing a code.

 

[pappy]

I don't know much about smog but have you bothered checking for engine codes? Tps might be bad or something could be a throwing a code.

Ya, start there.

... and occasionally you'll hear a miss at the pipe.

I hate to say this, but an occasional miss is NORMAL for a 22RE.

After looking at everything you have done, which is great, I'm starting to lean toward something more sinister. Inside the engine harness are several splices to the fuel injectors. They corrode. It's a common repair, and I'm leaning toward this as the problem. You will need to pull the plenum, disconnect the injectors, and peal back the harness. You will see the crimp splices. Injectors 1 & 2 are wired together, and 3 & 4 are also wired together. Plus all the commons come together from all four injectors. Those splices are probably going to be very green, if not broken.

You can also just pull the harness out and fix it on the garage floor (what I ended up doing).

 

[SPANNERSPINNER]

Thanks guys.

I haven't pulled codes, I just jumped in. I assume its throwing a misfire code. I'm not even sure the CEL works. I'll have to light it up tomorrow before I do other work.

God I hope its not the harness. I saw that elsewhere too and thought since I could hear my injectors ticking and could smell gas in the exhaust I was in the clear but if I have to pull the thing apart for the injectors (assuming I have to go that far) I might as well check. The way the problem manifests, in that its intermittent, feels electrical.

The misfire isn't infrequent when its present. When the engine decides it is going to misfire it runs rough consistently. Then i drive it for 5 min and its smooth. Then 10 min later its rough again. When its smooth, its smooth consistently, if that makes sense. I was reading elsewhere about checking the fuel pressure regulator for high pressure.

I should have mentioned, the engine is new to the car. The PO stated it was a rebuilt that was installed 40k before I bought it and the engine's appearance bares that out.

Could it be a lean misfire? Not enough fuel entering the combustion chamber causes poor or nonexistent burn leading to high HC in the emissions and no combustion despite all the other requirements present?

Its also had a fuel and air filter change from when I first bought it (fuel, oil, air filters and new oil all less than three hundred miles ago). I usually do it as an initial service when in buy a used vehicle.

 

[snobdds]

I would be looking at your EGR, PAIR, the Cat and the o2 sensor. Clean the EGR and check that it's working. Since your in Cali, you "should" have a EGR temperature sensor in it. Make sure it's not all carbon uped. If it's not an original Cali truck, then just clean the EGR. The PAIR is just a reed valve that injects air at idle and when letting off the gas. Make sure the VSV for the PAIR has all the correct vacuum hoses and works. The o2 sensor can be ohmed out to see if its good. The Cat is the one thing that really can't be tested. Maybe just switch a new one in.

 

[SPANNERSPINNER]

Valve cover is off. Locating TDC on #1 but... This is weird. The timing marks on the cam are ever so slightly forward, but the timing mark on the harmonic balancer is about 1/2 and inch beyond the 0* mark. Could this be it? Are the can and crank misaligned? Did I just sign on for a donky-load more work?

 

[KLF]

The dimple on the top sprocket should be at about the 11:30 position when the balancer is at 0deg:

 

[SPANNERSPINNER]

Sure enough. Okay, so the cam is right. Valves on #1 are loose, intake on #2 is loose, and everything on #3 and #4 are tight where the exhaust on #3 should be loose and #4 should be all tight.

The engine if cooled off at this point but cold adjustment on #3 has got to be better than misadjustment.

Edit: corrected origin valve setup.

 

[KLF]

If both #1 valves are loose when the crank is at 0deg, then you are at TDC for #1. Set the loose valves, spin the crank once, then do the others.

 

[SPANNERSPINNER]

Thank you! Valves adjusted cold and she runs MUCH better. The miss is all but gone. Ill have to adjust the valves hot next weekend. Now the idle wants to surge between 600 and 1200 rpm and, when it holds steady, it wants to hold at 1200 rpm. It also cut power on me at about 2300 rpm while sitting in the driveway.

Tps?

 

[KLF]

Check the TPS adjustment, then make sure you don't have a vacuum leak. Also make sure the intake tube & elbows don't have any cracks.

 

[SPANNERSPINNER]

I haven't had the chance to test the tps just get but I have been driving it. The idle surges only when my foot is on the brake, otherwise it idles steady at 1200RPM. I pulled the info from Roger Brown's website and will do the diagnostic this weekend.

Thanks again for all your help.

 

[Mudder]

That issue is covered in the FAQ I believe. The idle changing when the brakes are pressed

 

[SPANNERSPINNER]

I'll check it out. Thank you.

 

[SPANNERSPINNER]

Adjusted the idle lower and its a bit better. I also checked for vacuum leaks (albeit when it wasn't acting up) and the engine holds 21" of vacuum steady. If this doesn't cut it (I'm being lazy and shouldn't be) I'll go after the break booster check valve and then the throttle position sensor and dashpot.

And hey, my temp gauge works occasionally now so its nice I'm getting incidental benefits.

 

[SPANNERSPINNER]

I wanted to come back to this thread in the hopes that someone else might benefit from my fun. After a boat-load of playing around with a bunch of inputs on the old vacuum-tube computer here is what worked.

1. I had the idle TOO HIGH. This is why the idle was surging when I stepped on my brake. There was no leak in the brake booster vacuum line or in the booster itself. The engine does idle up a little bit when the brakes are pressed, which would then push the vehicle over 1200 RPM, causing the computer to cut fuel, bringing the idle back down, causing the computer to re-apply fuel, causing the idle to go back up, with the brakes pressed.... lather. rinse. repeat. I can't really say why the idle was set too high. I think all the other factors played with the adjusted idle and once the engine was hot it would surge when the brake was pressed.

2. My Throttle Body was all gunked up. And seafoaming it had made it worse because it just loosened part of the sludge up beyond the throttle plate, making it mobile, and causing it to move to places that blocked more airflow. I pulled the throttle body, cleaned the crap out of it with throttle body cleaner, including all the nooks and crannies and whatnot and re-installed it. I think it's the cleanest thing on my engine now.

3. My Catalytic Converter was toast. I didn't know it but it had clogged up. This played with my idle, caused the occasional missfire, and I think screwed with the computer making the sensors push data to the computer that made it adjust for things that weren't really an issue. Eventually it blew and it took me a day to figure out what sounded like pennies in a soda can under my vehicle. I replaced this and everything immediately started running better. The misses that were there on the way to the muffler shop weren't there on the way home and I had to work harder to get the brake-related idle surge to happen.

After all of the above, I took it for a good drive, got the engine good and hot, and adjusted the valves one more time, after making sure the timing was good and then went for a smog. Passed smog with flying colors.

There are still some issues - I think the cold engine idle-up switch isn't working properly as I have to give it a bit of gas when I first start it in the mornings to get the engine to run but can then take my foot off the gas and it runs fine.

Now I have to replace the suspension. Now that it's properly registered and I'm driving it more the damn thing hits the bump-stops front and rear over every crack and crevice in the freeway.

Thanks for all your help!