ae86 exhaust system clogged

phanist
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ae86 exhaust system clogged

Postby phanist » Fri Sep 27, 2013 2:10 am

hi guy

ok so my car was running pretty nice and smooth . then i notice i have a oil leak due to some not very tight oil relocated kit i have.. so i remove the header to have more room to work with.. after tighten all the line etc.. and put every back and go for a test drive.. i feel like my car have no power ..and feel like the exhaust not letting the air out... after thinking it have something to do with me removing the header and not bolting it back on right i remove and reinstall check everything seem nicely fit. but my car still feel like it choke...and restricted... i then with the engine running look down along the exhaust pipe and FIND that the cat convertor is RED HOT like if you were burning metal in high flame for long time...... is this a sign of it being clogged ? if so what may cause this problem and what to do to fix it?
im thinking just use a test pipe and bypass the convertor ...
or should maybe remove the cat convertor and clean it?

ok i cat convertor remove and installed a test pipe. that didnt help.. still restricted .
notice this is a fully rebuilt 20v BT
new valve new spring new gasket new cam shaft new piston ring new rod bearing ..

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jondee86
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Re: ae86 exhaust system clogged

Postby jondee86 » Fri Sep 27, 2013 3:22 pm

Copy and paste to save me typing the whole thing :)
Excess Fuel Entering Exhaust.
The fuel that powers your vehicle is meant to burn in the combustion chamber only.
Any fuel that leaves the combustion chamber unburned will enter the exhaust system
and light-off when it reaches the catalytic converter. This can super-heat the converter
far above normal operating conditions and cause a meltdown. Possible causes are an
incorrect fuel mixture, incorrect timing, corroded spark plugs, a faulty oxygen sensor,
sticking float, faulty fuel injector or a malfunctioning check valve.

Check for any of these problems. Maybe start with O2 sensor plug not connected, and
did the hose fall off the MAP sensor ?

Cheers... jondee86
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Re: ae86 exhaust system clogged

Postby phanist » Sat Sep 28, 2013 10:04 pm

running my exhaust system without a cat convertor is not what i intended to do.. i just do to clear and narrow down my problem.. my cat convertor was working fine.. then out of a sudden it clogged i need to know why and fix my car.. so i started by clearing the exhaust system... BTW i dont like how it sound with out the CAT......

so i finally got around to do a compression check ...on all cylinder .

cylinder test dry / tested wet.
#1 150 #1 170
#2 135 #2 155
#3 155 #3 168
#4 155 #4 168
cylinder #2 clearly show low compression... below spec....... this spell trouble
Note this is a fully rebuilt motor just been test drive after installed .........rebuilt done by a machine shop........

any body have experience and idea what i can do before i bring it back to the machine shop for repair?

about the being selfish ....running my exhaust without the CAT.. you trying telling all the motor CYCLE moped and scooter about that yet? LOL

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Re: ae86 exhaust system clogged

Postby jondee86 » Sun Sep 29, 2013 6:38 pm

OP did not indicate that he was planning to run his car without a cat permanently,
so off-topic posts in this thread about the rights and wrongs of running cars without
cats have been (and will be) deleted. Thanks.
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

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Re: ae86 exhaust system clogged

Postby jondee86 » Sun Sep 29, 2013 6:58 pm

phanist wrote:Note this is a fully rebuilt motor just been test drive after installed .........rebuilt done by a
machine shop........ any body have experience and idea what i can do before i bring it back
to the machine shop for repair?

As a general rule, engines don't like to be idled or driven at light throttle for 500 miles
after a full re-build. The rings need to be pressed hard against the cylinder walls for
bedding them in, and this is usually done by a series of short runs at higher and higher
load/rpm, with a cool down period in between. Allowing the engine to develop high
vacuum on the overrun (engine braking) is an important part of the process.

If you have not been able to do this, then the rings may not have bedded correctly on
the cylinder that reads low. Depending on how the engine has been used since it was
first fired up, you may find that it improves to match the others after you complete
the correct breaking-in procedure.

Cheers... jondee86
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persists in trying to adapt the world to himself. Therefore, all progress
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Re: ae86 exhaust system clogged

Postby phanist » Sun Sep 29, 2013 7:29 pm

Jondee

I think u could very much be right.
I haven done the correct break in process yet.
I hope it not too late to still do the break in.
But i will try do it now any way an hopefully that what the issue is..
I was in such a hurry to see what this engine can do over my stock 16v... For all the money i throw into it.. I didnt realize there is a break-in process need to be done before it could be driven like a normal car. Tt
...
Ok so here is how i see and hear the engine at idling ...when i got it running and keep it running for a while.
On start up it run at a bit higher rpm then after a minute or two it drop rpm but engine shake ... And vibrate .
To my noobish i never have an fully rebuilt motor before and not knowing what should be done to it before take it for a drive around the block.. I thought the shaking and rattle is from my stiff cusco engine and tranny mount ... But after this compress test i think it more of an unbalance cylinder compression so the engine doesnt run smootly likenit should.
Thank to your info and gaijin i learn more..
Thank you again

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jondee86
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Breaking in a new engine...

Postby jondee86 » Sun Sep 29, 2013 8:44 pm

The following is stolen and adapted from here...
http://www.mototuneusa.com/break_in_secrets.htm

Disclaimer: The following recommendations are based on my experience
with my own cars, from reading, and from talking with people who build
engines for a living. You can take it or leave it as you choose. This break-in
procedure should not cause any harm to a correctly machined and assembled
re-built engine. But I don't know what was done to your engine, haven't seen
it, and can't hear it. So don't tell me if something breaks because you forgot
to torque the big ends :)

1. Fill your engine with fresh mineral oil, then warm the engine up
completely !! Better to do this by actually driving around the block than
letting it idle. Head towards the nearest quiet piece of road where speeding
up and slowing down won't cause someone to run in the back of your car. Then...

2. Using 2nd gear:
Do Three 1/2 Throttle runs from 40% - 60% of your engine's max rpm.
Always allowing the car to slow down using engine braking (foot off throttle).

3. Using 2nd or 3rd gear
Do Three 3/4 Throttle runs from 40% - 80% of your engine's max rpm.
Always allowing the car to slow down using engine braking.

4. Using 3rd gear
Do Three Full Throttle runs from 30% - 100% of your engine's max rpm.
Always allowing the car to slow down using engine braking.

Continue driving using the gears and varying your speed. Change the oil and
filter. Congratulations... your engine is now run in :)

Note that which gear you use is not critical. Obviously, unless you are on a
deserted highway, redline in 3rd will likely get you in trouble. The important
thing is load and unload the engine by using alternating short bursts of
acceleration and deceleration
. Even while warming up your engine you can
be easing on and off the throttle.

The worst thing you can do for your engine is "granny drive" the car !!!

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

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Re: ae86 exhaust system clogged

Postby yoshimitsuspeed » Sun Sep 29, 2013 10:28 pm

For a 20v all your compression numbers are scary low. Unless you are like me and live at 6000 feet above sea level. Even up here I pull 160 across the board which is equivalent to about 200 PSI at sea level which is about where it should be.
95% of your ring break in happens in the first 20 min of running time. If they don't break in right by then there isn't much chance they will.
You could still try the method jondee posted just to see if you can bring up your numbers but your odds are about as good as bringing a cat back to life after being run over by an 18 wheeler.
If you are near sea level I would pull it back apart if you can't get over 180 PSI across the board.
It would be worth popping the valve covers and checking your valve shim clearance especially on the low cyl. Maybe you will get lucky and find a few shims that are too tight.
I have a 20v shim bank setup so if you need shims feel free to contact me.

Also double check your cam/crank timing. If you are a tooth off this could effect compression and make it feel gutless.

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Re: ae86 exhaust system clogged

Postby phanist » Mon Sep 30, 2013 12:10 pm

i checked the crank /cam timing they are align correctly. all the dimple meet where they should meet. and im in hawaii... and odnt think im 1000feet above sea level. but if stay too high above sea level give me a low compression reading... my cylinder 2 still produce a much lower compression then other three.
and yes sir.. i will contact you after i try the break method again.. if need shim .....
thank you

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Re: ae86 exhaust system clogged

Postby phanist » Thu Oct 10, 2013 4:54 pm

Update

Can't try the engine break in method per above advice..
My car not running right. Engine start up idle Ok.. Whole car on jack stand. Put into gear and drive . It run a bit rough.. Every gear work ... But weird usually it have it on the jack stand like that when in 2nd and higher gear without having to sit in the car and step on throttle the car run and spin at what ever gear that u put it in but at a slow speed but not slow enough to die out.... But now if I do that it die out if I m not stepping on throttle ... ...
So I lower the car and road test...
I barely get out of my drive way... It feel like something it holding it back...
Note on the compression test... I was using a mobile 1 synthetic oil.. Which I find out that was a wrong thing to do... For break in period ... So I drain the oil refill with 20w-50 regular oil ... Idle a bit test.. Turn off and done a compression. Test ... This time reading still low compare service manual ... All cylinder read about 165-170
Which bring all cylinder to about the same compression. But engine still idle but a bit shaky at some point.
So still don't know exactly why and what hold it back like this...
Tranny just been rebuilt by professional and tested ...

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Re: ae86 exhaust system clogged

Postby jondee86 » Thu Oct 10, 2013 11:59 pm

Dude... you have got some kind of a timing problem. Maybe the cams are not timed
to the crank pulley, or maybe the exhaust cam sprocket is on back to front, or maybe
squirrels made a nest in your exhaust :shock: I would guess that your exhaust valves
are opening too soon and/or your ignition is way retarded, so that you are not getting
complete combustion in the cylinders. Unburned fuel is going into the exhaust and
causing your cat to work overtime.

What modifications have been done to the engine ? What cams are you running ?
Pistons ? Cam pulleys ? Head gasket ? Head been machined ? What ECU ? Injectors ?

Only asking for a bit of background... I still think its a timing problem !!

Cheers... jondee86
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persists in trying to adapt the world to himself. Therefore, all progress
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Re: ae86 exhaust system clogged

Postby phanist » Fri Oct 11, 2013 1:41 am

hi
these are the part that i use when done the rebuilt.
tomei cam. i believe it the Pon cam
king bearing custom valve which is ferrea valve and spring
some harmanic balancer i think it BHT
power enterprise timing belt
toda oil pump gear
windage tray
carrillo rods
new piston ring
new timing belt tensioner
ported oil pump
and complete over haul kit from toyota.
then i get some t3 water pump and alternator pulley..
running sam-Q water kit. and COP setup
stock cam pulley
stock head gasket
blacktop ecu
a 3angle valve job is standard when doing a rebuilt the machine shop say.
in neutral and it idle and i can rev it.. car on jack stand andin gear it run and hit at least 60mph in 3rd gear.

i still have my stock bluetop in perfect running condition.. maybe i well pull this engine off and put the bluetop back. if the same thing happen then it not engine.
i have a good feeling it my clutch..it sound a bit weird and grab and release and i can feel the vibration at that part of the car... maybe bad pressure plate. this same clutch was on this same engine on my first test drive after rebuilt. one of my clutch pressure plate bolt snap causing my the flywheel and clutch to get stuck an not turnable . the bolt that snap stuck between the bell housing and flywheel. so maybe this clutch it bad now...
i well wait for the new flywheel and clutch to test . if that not the case i will pull this motor off and put the bluetop back .....

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Re: ae86 exhaust system clogged

Postby phanist » Tue Oct 15, 2013 4:14 am

Case close... After carefully rechecking everything..
The cause to my engine being weak and gutless was because of a fault Coil on plug.. The plug on top the cop were cracked causing no sparking . Im guessing fuel enter that cylinder unburn come off header then cat convertor cyhen burn there cause it to turn cheery red.

So when car were on jack stand it running without any load/weight but when i lower it to ground that become 2k+ pound.. With just three cylinder running it too weak to move and eventually die out. ...
Stupid me should check carefully first...cost me some money and time tt

Any way thank all for helping trouble shooting..

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Re: ae86 exhaust system clogged

Postby SolidSTI » Tue Oct 15, 2013 7:02 am

Glad you found the issue.

In a previous post you mentioned the sound of a test pipe. This guy makes a test pipe using a louvered resonator. When I installed it, I could honestly not tell a difference in sound.

http://www.sv3power.com/store/index.php ... cts_id=183
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Re: ae86 exhaust system clogged

Postby phanist » Tue Oct 15, 2013 11:49 am

oh thank
it should of come 1 week sooner . i already order a high flow catalytic convertor. and on the way here/.. tt
but i appreciate you for the info.. i can use it for future when needed. thank you.

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Re: ae86 exhaust system clogged

Postby phanist » Thu Oct 24, 2013 2:35 am

jondee

my compression reading on all cylinder now come in at about 180 is that pretty OK? after i retry the break in method u post... which is better then before..
thank you for the info...maybe i change the oil and repeat it a couple time more..

also is it safe to use synthetic oil yet?
my oil gauge reading my oil pressor a bit closer to the hot side....is that normal for the bt swap>?

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Re: ae86 exhaust system clogged

Postby jondee86 » Thu Oct 24, 2013 3:59 pm

Your engine is already broken in if you have completed the procedure I posted. Now you
should change the oil and filter and drive the car in a "sporting" manner. This means
constantly varying the engine speed and load by using all the gears. And don´t be afraid
to run it to red line now and then.

Because the camshaft design (timing) can affect your static compression, having similar
numbers across all cylinders is more important than the actual number. Put at least 1000
enthusiastic km on the engine with mineral oil before you change to synthetic.

Cheers... jondee86
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persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

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Re: ae86 exhaust system clogged

Postby phanist » Fri Oct 25, 2013 3:33 am

will do
thank man..
cheer