AE82 4age lack of power

[Herbs]

hi guys,

 

   i'm new to the thread/forum world. i'm after some knowledge and advice. I've picked up a nice little 1988 twin cam. it's pretty tidy and came with a few spare parts. i owned one of these years ago and it went really well. this one not as good though.

i don't know a lot of it's history, but it sounds like it was owned by a mechanic, and had a bit of a freshen up engine wise but no major mods that i know of. 

the thing is though it lacks a lot of power, it revs very poorly and when it should start to do it's thing around the 4000 rpm mark there is very little rev or power change. i haven't started playing with plugs or timing yet. it does have extractors and exhaust. standard airbox. 

the only leak it has seems to be from the dizzy.

the car runs really well but, nice and smooth although the idle it super low, below 800rpm

 

cheers

herbs

[ke70dave]

hi mate, welcome to the forum. AE82 4age, fun little car.

Here is what i would check in order:

- Engine ecu codes 
-ignition timing
-clean and regap spark plugs, check dizzy cap and rotor condition
-check the TVIS solenoid is plugged in and the vac lines are in good condition
-confirm fuel pressure
-adjust TPS
-make sure MAP sensor vac line is in good condition
-Camshaft timing

If you have all of those things in order, technically you should be motoring......

 

 

 

[Herbs]

thanks ke70dave. I've only ever played with old fords so a few of these things I'm going to have to do my research for this one. i love the look of the little hatch. the one i had years ago went really good but whoever had it before hand had made it that way i'm assuming. the one i have now my 4 year old could nearly run the quarter quicker (it might not be that bad haha) 

Edited November 17, 2017 by Herbs

[parrot]

Well there are mechanics, and then there are mechanics.  

I would do a compression check, make sure the cam timing is right, ignition timing is right & replace the fuel filter.

Then I would go here http://www.aeu86.org/technical/ae86-manuals/

and download the 4AGE Diagnostics manual.

It looks complicated, but really it isn't.  Make sure the throttle position sensor is set properly and follow the various diagnostic charts.  You will need a multimeter but they aren't expensive.

These engines are pretty foolproof, as long as the sensors are set correctly and the basics like compression and timing are correct.

ECU's don't fail, neither do coil / igniters. Keep it simple and work through methodically and it will run great.

[rebuilder86]

what sort of distributor has this thing got? is there any centrifugal advance on it or is it all electric? I ask because it kinda sounds like its simply lacking any timing. thats how my 4k ran when i ziptied the mechanical advance together for testing.

[7000rpm]

I was playing with one recently that was sluggish. I found the cat was blocked and the igniton timing was retarded.

I would also check that the tvis valves are shut under 4000ish rpm and opening after wards

On a car of this age, I would flush the fuel injectors, change the fuel filter and clean out the throttle body (carby cleaner). This is more updating the maintenance than fixing issues. It's common there will be gunk between the throttle butterfly and the housing, reducing air flow at idle.

[rebuilder86]

23 hours ago, parrot said:

ECU's don't fail, neither do coil / igniters. 

say whaaat.

ive had 2 cracked ecu boards in my time hahah. nissan pulsar 1990ish and mazda 323 astina BJ series 2000sumthing. 

[parrot]

Sorry, let me clarify that. Toyota ECU’s don’t fail. 

Mindful that you’re the guy who modifies carbie jets with an angle grinder as I recall.... Stupid app won’t let me put an emoji in, but I’m a bit old for all that anyway. 

[Herbs]

Thanks very much guys. I’ll definately have a look at all that. 

To do the timing, do you need to bridge something out. I remember on my ae86 the was a little box on the shocky tower but this one doesn’t have that. Could it be somewhere else? Or does the 82 not require to do that bridge out?

[rebuilder86]

15 hours ago, parrot said:

Sorry, let me clarify that. Toyota ECU’s don’t fail. 

Mindful that you’re the guy who modifies carbie jets with an angle grinder as I recall.... 

haha.

I feel all cozy inside that someone remembers. It gave me a perfect idle and now i have clean brown perfect plugs!!!  haha. 

Perhaps that is a valid argument about toyota ECU. They currently make the most reliable cars in the world, and thats a statistical fact. (google reliability index and find the .uk site)

I am not trying to prove u wrong to make a point or anything and i highly doubt the ECU is faulty, but toyotas suffer failures too.

http://www.toyotanation.com/forum/#/topics/1059849

http://www.carproblemzoo.com/toyota/corolla/computer-failure-problems.php

Edited November 19, 2017 by rebuilder86

[rebuilder86]

here ya go bud. here are the 2 pages of interest to u. these pages are the wrong way around, start at bottom of second one, there u find the appropriate jumpers to disable the advance.

Edited November 19, 2017 by rebuilder86

[Herbs]

Sorry for the dark photo. Are one of these yellow plugs the the one to short out to do the timing?? Nothing on the shocky tower

[parrot]

The yellow plug on the left with the rubber cap

edit: the black cap. Use a short piece of wire with a male crimped terminal at each end. 

Edited November 19, 2017 by parrot

[Herbs]

Thanks parrot. 

[Hiro Protagonist]

On 11/18/2017 at 8:58 PM, parrot said:

Toyota ECU’s don’t fail.

Toyota ECUs are well known to suffer from leaking capacitors, at least Jap ones from the 90s.