Brian’s FAQ for the new AE86 owner

Okay, here’s a collection of common issues with the AE86 RWD Corollas with some personal
experience thrown in for good measure.


Q: How long does a 4ag engine last, when maintained regularly?
A: A very good friend of mine beat the crap out of his 1985 corolla GTS coupe for 400,000km before he sold it because the body was too rusty for his taste. He used regular 10w30 oil, and tagged the rev limiter at least once a day.

Q: My engine leaks oil. What are the popular causes?
A: oil below distributor = distributor o-ring ($5 from the dealer)
oil inside distributor cap = distributor shaft seal (contact K-box for the kit)
oil inside sparkplug tubes = valve cover gaskets
oil inside sparkplug tubes after changing v/c gsk = those pesky aluminum
o-rings under the hex plugs.

Q: How do I fix the oil leaks?
A: Pinpoint the cause of the leak by cleaning up the mess as much as possible.
Engine degreaser plus a hose will work. Brake cleaner and compressed air will
work too. After you pinpoint, then replace the offending 20-year-old seals.

Q: Okay, I fixed the valvecover and dizzy o-ring, but I still got leaks. Where next?
A: Wash off engine, and look carefully with a light.
oil inside the timing cover = cam seals, maybe crank seal
oil below oil filter = filter, or housing gaskets, or cooler hose fittings
oil between engine and transmission = rear main seal (replace with clutch job)

Q: My engine smokes. Help!
A: Excessive white smoke is coolant, and has a distinct sweet/burning smell.
Blue smoke is oil, caused by bad piston rings or valve stem seals. Black smoke
= running too rich. All of these need to go to a good 4ag technician.



Q: I get a whirring noise from the rear of the car, and it changes in tone when
I accelerate/decelerate

A: Might be your differential gears. Have you checked your diff oil lately?
Are there any leaks? (edit: sometimes replacing diff carrier bearings helps
reduce this noise. Some people have had luck with synthetic "shockproof"
gear oils as well. YMMV)

Q: It’s hard to down shift into 2nd gear from 3rd. I get grinding/crunch noise
when I shift hard

A: 2nd gear synchro is worn out. Hard shifting can be a simple repair, but not
if you leave it for too long. (edit: Then it gets really expensive.)

Q: Can I fix my transmission with chemicals?
A: If your trans isn’t shifting well, sometimes a proper transmission oil will
really help. Many people have good experiences with GM synchromesh, also available
from Chrysler as "Synchromesh oil." My personal favorite is Redline
MTL or Redline MT-90, both of which are full synthetic oils, and cost around
$14/quart. You need 2 quarts of oil, and two gaskets to change your trans oil.
You can pump it in from below, or take out your shifter and pour it in through
the shifter hole, until fluid comes out the "fill hole."

Q: My trans is noisy going into reverse
A: It’s probably not transmission, but more likely a sticking clutch. Here’s
the test: Blip gas to 1500 rpm, allow revs to drop to idle. Hold clutch pedal
to the floor, and shift into 3, and then R. If you get a grind going into R
then try another gear, like 4th then to Rev. If it persists, your clutch is
not entirely releasing when you hold the pedal down.


Sticky Clutch

Q: Okay, if my clutch is sticking, what are the common causes?
A: In order of popularity, I’d start with bad hydraulics, too many floormats or
improper pedal adjustment, bad clutch disc or sticky splines on input shaft (not
too common), disc worn out, or flywheel worn out. (edit: a bad pilot bearing will
also cause the clutch to stick)

Q: Bad hydraulics? How do I check that?
A: A leaking clutch master or slave cylinder would not give you proper travel.
External leaks are easy to spot, and your clutch fluid reservoir would be low,
even when you top it up regularly. The clutch slave on the GTS is on the passenger
side of the trans bellhousing. The master cylinder usually leaks into the car,
along the pushrod, and gets the floormats wet. Sometimes the clutch flex hose
leaks too. Remember to top up with BRAKE FLUID. Any other fluids
will damage your hydraulics. DO NOT USE OIL.

Q: My clutch master cylinder leaks into the car. How do I fix it?
A: You replace it. Go buy a new one from the dealer. The ones from the later
cars (Kouki, 86-87) are an updated design and are a direct fit for the early

Q: My clutch slave cylinder is leaking onto the floor (edit: ground, as in
outside the car). Do I just replace that too?

A: Yes. I always do the clutch master and slave together, to save time and aggravation.
When one leaks, the other will leak in a few weeks/months anyways. The master
and slave is about $200 from the dealer. Get a bottle of brake fluid and brake
cleaner while you’re at the dealer.

kouki clutch master cylinder 31410-12182 $148.20
clutch slave cylinder 31470-12050 $92.90

Q: So can I do it myself? Do I need special tools?
A: If you’ve done brake work before, you can probably handle this one. It’s
a pain in the @ss job to do though, and takes a Toyota Technician about 1.5
hours. It will probably take you 2 or 3 to do, if you’ve got a good selection
of sockets and extensions. You will need a 10mm flare nut wrench
to do the master, and a 12mm flare nut wrench to do the slave. General procedure:
suck all fluid from reservoir (turkey baster or equiv. Get one from the dollar
store, don’t use mom’s from the kitchen!), remove brake booster nuts (4, 12mm)
from inside the car, remove clutch pedal clevis pin, pull booster forward 1~2"
and then remove the clutch master. Put in new master, then bleed system. If
you change the slave cylinder at the same time, you only have to bleed once.
You save fluid costs and time.


No Heat

Q: My car has no heat. The fan works but blows cold air. Help?
A: Lots of things to check. Thermostat (proper warmup), coolant (level and condition),
heater control valve, heater core.

Q: How do I check the coolant level and condition?
A: The coolant reservoir should be between the max and min marks. On a cold
engine, open the rad cap and check to see that the coolant is full to the top
of the rad neck. Sniff it. If the coolant smells like rotten fish, it’s time
for a coolant change. On a warm engine, grab the upper rad hose and give it
a good squeeze. It should be firm, with 12-15psi pressure inside. If you can
hear gurgling in the reserve tank, you need a rad cap.

Q: How do I check the thermostat?
A: When the engine starts up cold, the upper rad hose warms up and gets HOT
(82 deg C, 180F) and the lower rad hose is COLD before the thermostat opens.
When the thermostat opens, the lower rad hose gradually warms up. A failed thermostat
(stuck open, or opening too soon) will allow both hoses to warm up to the same
temperature. IOW, the lower rad hose will warm up, before the upper one gets
HOT. (edit: Watch out for the moving fan blades and the moving belts. Many a
mechanic has lost a finger to a fan belt. Keep all of yours out of harms way.
Also, it can be very difficult to tell whether or not the thermostat is working
if the fan is blowing hard. You can slip a piece of cardboard in front of the
rad to block the airflow from the fan, or temporarily remove the fan and the
intake piping, put some flat washers under the nuts, and put the nuts back on
the waterpump pulley. After testing, you can put it back.)

Q: Heater valve?
A: Have an assistant move the heater lever from hot to cold and back again while
you watch the heater control valve. It’s on the firewall, right side, near the
wiper motor (on LHD cars). The plunger should move up and down. If it’s stuck,
you can manually move it to the open position for now. Order up some new heater
control cables and change them.

Q: Heater core?
A: Warm up the engine, make sure the heater valve is open (hot position) and
check the temperature of the heater core pipes. They’re on the center of the
firewall behind the cylinder head, attached to the heater hoses. Both pipes
should be HOT to the touch. If one’s hot, and the other’s not, then you’ve got
a plugged core.

In colder climates, you can actually remove the engine fan for the winter with
no real side effects. Just remove the 4 10mm nuts on the fan, pull it off, and
put some flat washers under the nuts, and put them back on. Tighten, run the
engine for a couple minutes, shut off the engine, and re-tighten those nuts.
When it warms up in the springtime, either put the regular fan back on, or do
an electric fan conversion. (edit: If you get stuck in bad traffic/gridlock,
keep an eye on your temp gauge. If it goes towards HOT, turn your heater on
max heat to help cool down. Your car won’t overheat if it’s moving. It’s time
for the electric fan conversion, or put the original fan back on)



WARNING: Brake and suspension work should be done by a qualified technician. If
you have no training, you’re taking your personal safety and that of others into
your own hands. If you’re not sure of what you’re doing, have a professional do
it, or at least get a 2nd opinion. Use only brake fluid in your
braking system. Other fluids will kill the rubber seals, and can cause brake failure,
leading to loss of property or death.

Q: My brake warning (!) light is on
A: This is caused by one of two things. 1) brake fluid low. or 2) handbrake
or handbrake switch

Q: My fluid is low, causing my brake warning (!) light to
come on

A: Check your brake pads, and check for fluid leaks. Once you’ve checked your
pads, and they’re all above 2mm, and evenly worn, you can top up your fluid
slightly and monitor for leaks. If your pads on the front or rear are close
to 2mm remaining, I’d put in new pads and rotors. Brembo makes fine quality,
affordable brake rotors. OE Toyota pads, or PBR/Metalmaster pads work great
for street use. If you’re on a tight budget, you can measure your rotors for
thickness, and just replace pads. But this is not a good idea. Fresh rotors
will give you better stopping. IMO, machining rotors are a waste of time and
resources, when rotors are relatively inexpensive.

Q: My brake fluid level is fine, my warning light (!) is on.
A: Unplug the float switch at the master cylinder to eliminate that possibility.
If the light stays on, then check the handbrake lever. Wiggle it up and down.
If the warning light blinks, try a new switch?

Q: My car doesn’t stop too good
A: Check the obvious (cheap) stuff first. Tire pressures, tread and tire "quality",
functioning shocks, etc. If you can skreech the tires, then your brakes are
working fine, and you need to concentrate elsewhere. Perhaps your front pads/rotors
are glazed over, or your expectations of what an ae86 can do are unrealistic.
Get a 2nd opinion from another ae86 driver.

Q: My brake pedal shakes when I use the brakes
A: That’s brake rotor warpage/thickness variation. You need to road test, and
determine whether it’s the front or rear. A quick brake pad inspection will
help too. When you road test, you can check for steering wheel shaking, or shaking
when the handbrake is applied. This will help you determine whether it’s the
front (steering wheel) or rear brakes (handbrake). Wobbly front wheel bearings
will also cause this condition. So will a bent rear axle flange (caused by kerbsurfing).

Q: My steering wheel shakes when I use the brakes.
A: Front rotors have a thickness variation, or run-out. Ya need new rotors.
Put new pads on at the same time, unless the pads are relatively new (8+mm),
and not worn at a taper. If the pads are worn at a taper, you need to service
the caliper sliders. Front rotors are behind the wheel hubs, which means the
wheel bearing assembly has to come apart. Inspect the bearings for play before
you disassemble. Do one side at a time. Don’t mix up left and right side parts.
Don’t drop the wheel bearings, a dented race = new bearing required. Bolt up
the new rotors, and torque them to spec. The front wheel bearings should be
set to zero clearance, with no preload. If you don’t understand this, you might
want professional help with your brakes. Don’t forget to pump up the pedal when
you’re done, before you start the engine otherwise you’ll crash
your precious car.

Q: My steering wheel shakes at around 100km, without using the brakes
A: This one’s not brake related. You likely have a wheel balance issue. If you’re
on OE rims, jack up the front of the car, and spin the tires, and check for
bumps/runout of the front tires. While the nose is up, inspect your front wheel
bearings for play. If they’re fine (zero play in both 12/6 o’clock directions
and zero play in 9/3 o’clock) then send your front tires for balancing, or try
rotating the tires to the back of the car. If the vibration at 100km/h moves
to the rear of the car, then you need to have your tires re-balanced. Non OE
rims may need to be properly centered on the hubs. Hub-centric spacers will
help a lot. Again, spin the tires and check visually for run-out. More than
about 5mm is considered excessive.

Q: My car shakes when I (carefully) apply the handbrake at speed (50kph should
do it)

A: Rear rotors have a thickness variation or run-out. Ya need new rotors. Put
pads in too. Rear brakes are different from fronts. Once you remove the caliper,
the rotor comes off. If it’s rusted, use an m8x1.25 bolt to "push"
the rotor off, using the threaded holes provided. The rear caliper pistons need
to be turned clockwise while you push them in to retract. There are special
tools availible to help you do this, or you can use needle-nose pliers in the
notches. If the piston doesn’t move easily, you should consider getting your
calipers rebuilt.

Q: My rear brakes are noisy
A: this one’s tough. A squeek is usually pads/rotor interface, or rusty rotors
(edges). A groan can be many things, sticking calipers, tapered pads, sticking
sliders, etc etc.

Q: My brakes are excessively spongy
A: several possible causes for this. 1) air in brake hydraulics. 2) tapered
pads caused by sticky calipers. 3) blown brake hoses. 4) unrealistic expectations
for a 20 year old car. A quick brake inspection, followed by new fluid and brake
bleeding will tell you lots. So will a second opinion from another ae86 driver.

Q: My handbrake doesn’t work
A: check to make sure you’ve got some rear pads remaining. Inspect rear brakes,
and have somebody pull the handbrake while you watch the caliper cam levers.
Check both sides of the car. Seized/broken/rusted cables, seized/stuck calipers,
worn pads, tapered pads, rusty rotors, all can cause the handbrake to not hold


Starting Problems

Q: My starter won’t crank, all I hear is a single click noise. I have a new battery
(or one that tests good.) My headlights are bright.

A: This is the most popular failure mode for the starter. The starter contacts
are worn out. It’s simple to fix. Parts are $45 from the dealership.

You’ll need o-rings for filter housing:
90029-20013 outer
96732-31060 inner

Starter contacts:
and a new oil filter.

Q: How do I change my starter contacts?
A: Get the parts. Find a 27mm socket. Disconnect the battery negative terminal.
Remove the starter. There are 2 bolts you can reach from the transmission side.
There is one small plug, and a nut for the battery wire. If you have headers,
you can pull the starter right out from the back. If you don’t, then remove
the oil filter and filter base (12mm + 27mm socket), then try to wiggle the
starter out. You may have to remove the exhaust heat shield inside the manifold.
Once the starter is out, remove the 3 screws and the metal endcap. Pull out
the plunger, you will now see the contacts. Put new ones in, and make sure they’re
not crooked. Put the wider contact on the battery wire side for longer life.
Clean up the plunger disc with a wire wheel, and then re-install the starter,
filter housing with new o-rings, and a new oil filter. Change your oil while
you’re there.

Q: The starter cranks but the engine won’t start.
A: Could be a bunch of things. First, check to see if your "check engine"
light comes on when you turn the key to the ON position. If it doesn’t light
up, your engine ECM has no power. If it does light up, you can check for spark.

Q: My CHECK engine light doesn’t come on with the key on.
A: Blown fuse? Check IG, AM1 and AM2.

Q: How do I check for spark?
A: Pull out a plug wire off the plugs, (any one) and put a philips screwdriver
(or equivilant) into the plug wire end. Hold the screwdriver shaft 1/4"
(5-6mm) away from any metal part of the engine (valvecover nuts work good, so
does the engine hanging hook) and have somebody crank your engine. You should
get a nice blue spark. If ya don’t then there’s your problem: something in the
ignition system is broken, or your engine Timing Belt is broken.

Q: No spark, now what?
A: Pull off the dizzy cap or the upper timing cover, and have somebody crank
the engine over for you. If the dizzy rotor doesn’t turn, your timing belt broke.
If it turns, then you’ll have to diagnose your ignition system, check the coil,
ignitor, etc.

Q: I got spark, now what?
A: Do you got gas? Is there fuel in the fuel tank? Can you hear the fuel pump
running when you blip the key? On the kouki (86+) corolla, you can jumper the
B+ and FP terminals in the DLC connector on the firewall. You should be able
to hear the fuel pump running, and hear fuel whooshing through the fuel rail.
On the zenki, you can unplug the AFM (airflow meter) and jumper the pair of
connectors at one end that sits apart from the rest in the plug, that will turn
on your fuel pump.


Modifications & Other

Okay, here’s where the big can of worms opens up. Everyone will have a different
opinion here. The following is my experience with any old car, especially 20+
year old cars.

Q: I just bought a RWD Corolla GTS. What’s the most effective way to make the
car go fast?

A: Most people think POWER is the key to going fast. I agree, but only to a
point. I believe that you can make the car faster by making it easier to drive
fast, to increase it’s grip and roadholding. Make it drive like it did when
it was new. First of all, you have to "sort" the car, and make sure
that everything works 100%. No sense in putting 2x the power into the car if
you’re riding on 4 different tires, now is there? Spend a few weeks, drive the
car, and fix everything that is broken. Make sure you have some decent tires
on the car, and that your shocks aren’t bagged out. Make sure that the car drives
straight on it’s own, and doesn’t wander excessively on smooth surfaces.

Q: I’ve driven the car for several weeks, put in new shocks, grippy tires,
and had the car aligned. Now what?

A: Once the car is mechanically sound, when everything works, the most effective
and fun modification is the addition of a limited-slip differential, or LSD.
The LSD will increase your traction on slippery surfaces. Also, when cornering
near the limits of adhesion, the break-away is smoother, and easier to recover
if your tail starts to slide. Very nice in winter conditions, in the wet, and
will make the car more fun in the dry too.

Q: Should I get the OE (original equipment) LSD, or an aftermarket (TRD, Cusco,
Kaaz, etc) one?

A: If your car came with an OE LSD, you can get it rebuilt for firmer lock up.
The aftermarket LSDs have larger clutch packs, with more friction plates, for
a much firmer lockup. Also, they are 4-pinion diffs, instead of the OE 2-pinion
diff. They’re much stronger, and less prone to exploding when abused. IMO, if
you’re going to get an LSD, get a TRD or Cusco one. The installation will cost
you around $3-400 anyways, for bearings, LSD oil, and labour. So skip the ebay
special used OE LSD which is probably worn out anyways, and not as strong/durable
for motorsport applications. Remember that in 1985, the tire technology wasn’t
as good as today. Today’s sticky street tires are easily more sticky than the
race-tires of yesteryear. And if you’re running R-compounds, you’re going to
break the OE LSD.

Q: My car sits really high, and even with the new shocks leans a lot in corners.
A: There’s two reasons to lower a car. If you’re doing it for looks, then IMO
you’re doing it for the wrong reasons. If you’re increasing the spring rates
to reduce body lean, and lowering the center-of-gravity (CG) for better cornering
ability, then do it right the first time. If your car came with dead shocks,
now is the time to decide how far you want to go with your car. If you’re going
beyond stage1, be sure to inspect all your suspension bushings, and consider
either a full TRD bushing set, or a polyurethane kit, either from Whiteline,
or Prothane. TRD bushings are quieter, more durable, and more difficult to install.
They also include new upper front shock mounts. The poly bushing kits are less
expensive, can squeak if not properly lubed, and are much easier to install
and replace when worn out. Poly kits do not include upper front shock mounts.

Suspension mods, basic setup:

Stage1: Tokico "blue" shocks, Eibach Pro-Kit springs

Stage2: Tokico Illumina adjustable shocks, TRD Japan 6kg front, 4kg rear. (edit:
TRD Japan springs)

Stage3: Coil-over front short-stroke suspension, KYB AGX or Tokico HTS shocks,
TRD-Japan rear springs,
adjustable panhard rod, and rear traction brackets. TRD or poly bushings.

Stage4: How much $$ you got? You probably don’t really need my suggestions here,
for aftermarket control arms, swaybars, tie rods, camber plates, RCA, etc etc.

For street use, I recommend a soft spring setup, no stiffer than 6kg front,
4kg rear springs. For track use, you may want higher spring rates, perhaps 8/6
or so. Remember, if you’re on a tight budget, but eventually want a semi-track
setup (Stage3) then you can always sell your stage1 or stage2 suspension to
another DK member and recover some of your costs. Keep in mind that everytime
you adjust the ride-height of your car, you’ll need to send it for a proper
alignment, including thrust angle. Also, it’s pretty straightforward to swap
spring rates on a coilover suspension, and you can always sell your old springs,
again to recover expenses.

Q: Okay tuffguy, I’m going to track/drift my AE86
A: Then you don’t need my help. You need a roll-cage. And a seamwelded chassis.
And a bit more horsepower, and plenty of track time. A spare car would be nice,
because a drift car doesn’t make a very good commuter car.