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v-tec
3rd November 2005, 02:38 PM
hey, my engine in the ae71 corolla i have is to say the least... really crap.

it really doesnt seem to rev well. after 4000rpm it starts slowing down and when it hits 4500rpm it acts like it hits a limiter or something. ( the revs just bounce down and it makes popping noises like what would be heard on a car with a limiter).

drft86 and i have been playing with the air/fuel mix in the carby a bit. Our guess was that its just been running really lean. The little glass thing on the side of the carby shows that there is less than half fuel running through, this was showing even after we cranked the air fuel mix up. and the car still ran the same (might have revd a little better but still did the same things).

I was talking to ken streeter yesterday as well, and he was saying to me he doesnt know much about the carby's on these corrola's.
Does that mean that the aus 4ac's in the corolla's and in the sprinters are different? if so how are they?

i know my car should be running better cause my mates old 4ac from the sprinter reved to like 7000rpm daily for a year and a half.

anyway, can anyone tell me what i need to be done to fix this engine? i do plan to put a 4age in sometime, but i untill then i do want to use this engine. and considering it would seem like most of my power is being made at 3500rpm... well im sure alot of you couldnt bear to be shifting that amount of revs when pushing your car http://www.ae86drivingclub.com.au/forums/emoticons/blink.gif

cheers
- Grant

Bustin_86
3rd November 2005, 06:55 PM
i dunno dude, but my 4ac seems to pull all the way to around 6-7 grand with no problems.

Might just be the carbie...or your engine might be rooted, i dunno.

God luck with it though!

CAE86
3rd November 2005, 07:38 PM
possibly check the fuel is getting to the carbie, might be a blocked fuel line, or maybe even a blocked carbie jet.

v-tec
3rd November 2005, 08:10 PM
ok cheers mate. ill have a look into that.
i dont know too much about carby's so i wouldnt have a clue other than that.

does anyone know if the engine is actually different to the 4ac in the sprinters?

EVIL 86
3rd November 2005, 08:11 PM
nope the corrola is the same engine as spoonter engine just fwd mounted so i cant see why there is different tuning involved

aslo the best way to see wats wrong is hook a vac gauge up to it and see what kinda reading ur getting and then go against the factory roller manual

v-tec
3rd November 2005, 08:15 PM
its actually a rwd car and rwd mounted, not fwd (the front wheel one is 4a-Lc)
ok, thats good that they are not different tho.

NickAE86
3rd November 2005, 08:22 PM
head might be f***ed. I overheated the 4ac in my old ae82 & it still ran fine enough but with symptoms very similar to what you're experiencing

i think the 4ac's between the rollas & sprinter would be the same...they're both shit http://www.ae86drivingclub.com.au/forums/emoticons/laugh.gif

bite the bullet and get a loan to buy the 4age package ken has for sale...diy you can have it in for under 2k http://www.ae86drivingclub.com.au/forums/emoticons/smile.gif

mumblezzz
3rd November 2005, 08:27 PM
Your coil is f***ed. Replace that and see how it goes. Mine had the same symptons when the coil took a shit.

v-tec
4th November 2005, 05:38 PM
how much do they cost for a working one?

thats the bit that leads up to the distributor isnt it?

Sprinter_Seth
4th November 2005, 06:37 PM
yeah i was gonna say that either your coil, plugs or leads are failing

mumblezzz
4th November 2005, 08:09 PM
http://www.onthenet.com.au/~pauls/Images/KE70/Coil%20Ig.jpg

The big silver cylinder like object.

Sprinter_Seth
4th November 2005, 08:17 PM
could also be the igniter box, the silver box mounted to the strut tower.

v-tec
5th November 2005, 04:28 PM
The big silver cylinder like object.[/b]

thanks mumblezzz, thats what i suspected it would be. Ill get one of them and see if thats the deal

v-tec
9th November 2005, 11:13 AM
i changed that over. the car seems to rev smoother and more efficiently, however, it still pretty much does the same thing. Starts losing power at 4000 and wont go past 4500

i guess it could be the carby or something

OBE353
13th November 2005, 05:53 PM
change plugs and leads if they r not new...makes a difference.

mine was doin the same thing i removed the air filter and it revs out alot better now and sounds better, illegal and not good for the motor though. if that works better get a new air filter.

could also b the points in the dizzy

Drift^Laurel
13th November 2005, 09:40 PM
i already have the filter off... sounds phat hey for a stock exhaust

i will change the plugs and leads when i get a chance, but very limited on time and money atm

cheers

Julz01
14th November 2005, 08:47 PM
Originally posted by mumblezzz@Nov 8 2005, 01:09 PM
http://www.onthenet.com.au/~pauls/Images/KE70/Coil%20Ig.jpg

The big silver cylinder like object.
The silver thing is an ignition coil

v-tec
21st November 2005, 03:04 PM
i changed the distributor cap as well today. cause the thing had heaps of build up in there. Seems to have made a small difference and can now rev to 5,500 rpm at some points... but mainly only goes till 5,000

hehe... im getting there but its still loosing power after 4...


btw, that post from drift laurel was me... i didnt log in as mine when i posted

SANMARU ZED
22nd November 2005, 12:07 AM
hey i have not had much to do with these particular engines but here are a phew things to look at.
The clear little round thing made of glass on the carb is the sight glass the fuel level should be exactly half way up this if not you will have to adjust your floats. Secondly check for play in the distributor shaft as at higher rpm it may be contacting with the pickups.
Have you changes the fuel filter and if you have have a look where the fuel goes into the carb and see if there is a bolt holding the inlet pipe on if there is good chance there is a small gauze behind this. After many years it will up with solidified petrol.
hope this helps

cheers doug http://www.ae86drivingclub.com.au/forums/emoticons/blink.gif

v-tec
22nd November 2005, 09:19 AM
cool thanks mate