9o7yota

My exhaust pipe after the manifold where the exhaust flange donut gaskets are, all the way up to the catalytic converter, was RED HOT yesterday on my third start up. I was leaking or smoking from the donut/flange gaskets, and thats where the red hot began.

I've researched, and it could be many things. two popular ones were the cat blocking the flow..but i have good flow from the exhaust tips(i have dual pipes that Y out after the cat, no mufflers).

The other idea, is the truck is running too lean.

It does run a little rough, even after i put it in time. I needed to adjust my throttle cable to not let the throttle go completely to idle. Increasing my idle with the screw would not help a whole lot.

Any ideas?? is this normal for a rebuild? I did not rebuild my head. Could my valves be way off now and running too hot? ideas?

shaeff

Check your ignition timing. If you're too far advanced, it'll lean out and cause that. Also, it's not a bad idea to drop the cat and take a look. Those are the only two things that come to mind for your symptoms.

abecedarian

You adjusted the throttle cable?
If that's the case, you have something really odd going on. The idle bypass screw can bypass enough air to control the idle from less than 500 rpm to over 1200 rpm. Time to re-evaluate your setup.

abecedarian

And to screw with things a bit, a rich mixture can heat the pipes up too.

9o7yota

okay, yeah, with the idle screw, i would tighten it, and the engine would slow its rpms. Loosening it would raise them, but it would stop at a point and would be barely enough to keep the engine from really shaking.

I just started it a few mins ago. After retorquing the lower exhaust bolts, still no change. After a while it starts to come out of that area... but ONLY after it warms up for a bit.

Also, when i let the throttle cable relax completely, since i had it tightened to hold a slight amount of gas, i would hear the little compression thing that the throttle sits on...well it wouldnt stop making that noise..almost like there was an air leak once it went to full "rough" idle.

I tried to give it gas to see waht it would do. Yesterday it would rev up just fine. Today, giving it gas almost made it stall, and would make it shake. only if i floored it would it start to slowly..SLOWLY raise the rpms.. This is unique to todays start only. never did this before.

And the timing was set, i bought a timing light and set it yesterday. Putting it at the correct ignition timing made it run rougher and slower at idle than my original distrib position, but when i revved it up yesterday after timing it..it sounded pretty nice.... wellllllllllllllllllllll that was yesterday, not anymore.

abecedarian

When setting the timing, you jumped the diagnostic plug?

prmartin

sounds to me like the engine is running way to lean.maby take it to a shop and have it scanned to make sure all your sensors and computer are working correctly.also maby check fuel pressure and filter etc.

camo31_10.50

yea i've come to the conclusion that i'm just gonna take mine to the shop to have them adjust everything on my carburetor the right way..i can't get the damn thing to run right at all..lol

camo31_10.50

can't you adjust the air/fuel mixture somehow on the 22re??

and are you sure your Cat. converter aint clogged up???

what about your O2 sensors?

abecedarian

On the 22RE there is a little bit of idle fuel mix adjustment on the air flow meter. Above idle, it comes down to the throttle position sensor, air flow meter and coolant temp sensor to control the mixture with some feedback from the O2 sensor.
If the exhaust manifold is getting that hot, I'd guess that the fuel mix is rich, exhaust valves are too tight, and the PAIR system is doing what it's supposed to do: provide air to burn the fuel.
But that's just my guess.

9o7yota

I never adjusted my valves...could that be a problem?

When i timed it, i did not jump the diagnostic plug.

Im going to unbolt the cat after work and see if that changes anything..

VTToy

I think i would look at the cat. as the problem, if its starting to plug up it will make it run rough and make the exhaust get very hot. thats a very good first clue that its plugged.

camo31_10.50

welllll uhhmm..

FRICKIN DUH!!!! you need to set your valves first...do it cold.. .008 intake .012 exhaust i believe

then after that...you need to jump the terminal and set your timing....then report back..i doubt the cat will do anything...although it may seem like it because the exhaust gasses are able to escape quicker and therefore the pipe won't get AS HOT..idk where you're located..but unless you have smog tests...leave the cat off..and put a muffler on it..

Jay351

I bet the cat is plugged...

Since its getting redhot and blowing out the o-ring gasket before the cat..
Doesnt matter what kinda pipes you got after the cat( dual pipes are too much BTW) if is plugged.

Just pull the cat and see if its plugged up.

annoyingrob

Also, it's a really dumb thing, but make sure the electrical connector to your AFM didn't come loose.

shaeff

Hi, Rob! (shaeff from SM)

9o7yota

okay. i never rebuilt the head, so its all old parts. Ive never adjusted valves, and dont know how to..anyone got a good website to go to that will explain it? or can someone do it themselves so i can learn lol..


After the cat the pipes Y out to two pipes so i have tips on both sides of my truck..is that really too much? it didnt effect performance really..

and i live in anchorage alaska. We have to have cats here unfortunately.


Its strange, because my cat wasnt clogged the last time i drove it. ive only started my engine twice, and the first time i let it get warm was the second start, and that was the first time i saw the glowing pipe.

annoyingrob

What's with all of the Supra guys buying trucks now?

shaeff

I've had mine for nearly 5 years. But I don't know, I've noticed it too!

crawlerjunkie

my buddy had the same problem with his. Turned out to be timing and a bad pin on the tps. Actually cooked the welds on his headers.