Big flatspot on Bluetop 4AGE- but I think I might have an idea

Discussion and technical advice for 84-89 AW10 & AW11 MR2. 3A-LU, 4A-GE, 4A-GZE.

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shish
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Re: Big flatspot on Bluetop 4AGE- but I think I might have an idea

Post by shish »

thanks paul

the sensor from my old mr2 looks to be dead completly

i am going to wait until we get our replacement ecu and then retest everything again

it's the same part as the GZE sensor and is a 1v sensor
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Lauren
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Re: Big flatspot on Bluetop 4AGE- but I think I might have an idea

Post by Lauren »

Okay have fitted the new oxy sensor, thanks Paul. :+:

All checked and it's switching fine.

Also put in the stock ECU. Car seems to drive the same. Most notable difference was the rev limiter back in effect which felt a bit weird, but probably shows that I've been revving a bit past it on occasion.

Otherwise it feels smooth enough, if anything it feels more peppy at the lower end.

Will stick with it for a week, check economy/drivability etc and see what I think. The stock ECU can handle 264 degree duration camshafts apparently so it ought to be able to cope with it.
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Lauren
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Re: Big flatspot on Bluetop 4AGE- but I think I might have an idea

Post by Lauren »

Mark has been doing some digging with regard to the modded ECU, it seems the jumpers do things like switch the oxy sensor on or off, change the fueling and also can do things like change ignition advance.

There has been suggestion (thanks to AEU86.org) that it might be a Cusco/TRD type generic board whereby you have a board added that has additional maps plus the option of also altering other parameters via the jumper switches.

This kind of thing:
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shish
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Re: Big flatspot on Bluetop 4AGE- but I think I might have an idea

Post by shish »

i would also say that it could be a generic copy of a cusco board given the lack of the cusco supplied replacement front cover. Unlike ours which is simply bolted to the back of the stock cover with some spacers.

There are also differences with the switches, ours has less than the cusco mfe

i'm going to take the lid off again and trace that O2 line and see if (like the cusco) it runs through a switch.

The adjustment pot is for ignition timing apparently...

...more to come
shish
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Re: Big flatspot on Bluetop 4AGE- but I think I might have an idea

Post by shish »

sorry to bump an old thread but i finally got around to reading out the eprom on this and might be of interest to some.

looks like there are two maps in it, switchable from the dip switches i think.

I will probably do a follow up video soon and look where the address lines of the eprom go to.

https://www.youtube.com/watch?v=9vGQnsuRk_E
elbon50
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Re: Big flatspot on Bluetop 4AGE- but I think I might have an idea

Post by elbon50 »

shish wrote:I will probably do a follow up video soon and look where the address lines of the eprom go to.


I'll be very interested in all further info on this Mark :thumleft:
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1989 MR2 Mk1 NA T-bar
1998 Ssangyong Korando GLS
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tottacrolla
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Re: Big flatspot on Bluetop 4AGE- but I think I might have an idea

Post by tottacrolla »

Starting with the ten switches, each one has an on/off mode and up is on. I will list the function of each switch numbered 1-10 even though they will be numbered 1-4 1-6
Starting at switch one.
1 Enable (off) or disable (on) Lambda input
2 Enable (on) Cusco ignition timing map (off)= standard map
3 & 4 work in combination: on-on / off-off / on-off / off-on to select 4 different programs
N-1 : NORMAL ENGINE
N-H : HIGH CAM / NORMAL LIFT
S-N : SUPER CHARGE / NORMAL CAM
T-N : TURBO / NORMAL CAM

5 Enable fuel change (on) no fuel change= (off)
6 Rich (on) lean (off)
7 & 8 work in combination and in combination with switches 5 & 6: on-on 5% / on-off 10% / off-on 20% / off-off 40%
(so 5 on 6 off 7 & 8 on would give 5% lean on the "under load" map)
9 Enables idle fueling to be set by volume (on) use in conjunction with the potentiometer screw and switch no. 1 on
10 stays off
shish
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Re: Big flatspot on Bluetop 4AGE- but I think I might have an idea

Post by shish »

Thanks for the clarification of the switches.

The unit i have only has 7 dip switches, i will have to see if they correlate to meaningful settings against the 10 switch version.

there is also no mention of the adjustment pot or what the led indicates (there are holes cut in the cover to allow access to both of these so they must be somewhat important
acsmonster
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Ae86 cusco mfe 8 dip switch model

Post by acsmonster »

Sorry to start up on an old post

I recently obtained an ecu for my ae86.
It had a cusco cover on it but only had
8 switch as apposed to the what appears
To be the normal 10. I managed to send
Away to cusco Japan, except for the guy
Being In disbelief that 30 years on the
Ecu's are still out there working.
He managed to translate and send me
Some information on switch operation.
acsmonster
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Re: Ae86 cusco mfe 8 dip switch model

Post by acsmonster »

1 power on/off
2 fuel injection flowing high(on)/low(off)
fuel injection timing
3 on on off off
6% 12 25 50%
4 on off on off
5 02 control on/off
6 ignition cusco(on) standard(off)
7 always off!
8 high cam(on) standard(off)
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Lauren
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Re: Big flatspot on Bluetop 4AGE- but I think I might have an idea

Post by Lauren »

Thanks for that. If only I hadn't sold the car two months ago!
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