1989 ECU removal
Trying to swap out ECU with a known good one from another 1986 van with the same drivetrain. On the 86, removal is simple. One bolt through the wiring harness, and the unit is mounted flat against the firewall in the passenger footwell with the harness visible.
On the 89, the computer is mounted in about the same place but with the multi pin connector mounting directly into the firewall. And, of course, it doesn't just pull out. It's secured in there somehow. But I can't seem to see a bolt holding it in from the other side. I've looked under the wheel arch, looked as best I can behind the battery/throttle body, and looked from under the vehicle. Can't seem to find the bolt with all that crap in the way.
Anyone know how to get this thing out? TIA
But not how to get out.
I have the same Problem.
I want to install a performance module, but I cannot pull the ECU out of the Firewall.
It seems that the connector holds the ECU onto the Firewall.
I can't see the wiring harness from under the hood, because the blower housing is in the way.
But right of the ECU is a stud.
I didn't try yet to remove it, but i think if this stud is removed the ECU comes out with the plastic panel that is mounted on the firewall inside the passengers leg room
The stud next to the ECU is just a bolt that holds the Heater core housing.
I cannot get my arm far enough on the connector from the inside, but what i felt could be a lock.
So it seems that the connector of the ECU needs to be squished together on the right place.
I can't believe nobody here knows the answer to this. It is an odd design...
I cannot reach the Connector, because the Dipstick-Tube of the Transmission is in the way.
Or my arm is just too fat

All I know is that every Car I've worked on some sort of Lock on the ECU Connector had.
But there are different types - some of them had a lever, some a retainer
I dont have had a mirror to look around the corner, but it felt like there is a lock that needs to be pushed together.
The only alternative I see so far, is the one I try to avoid:
Taking out the blower and see what there is going on
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I may try to shove my phone in there and snap a photo so I can see what the heck is going on. If you would, let me know if you make any progress; I'll do the same. And thanks for not letting this thread die just yet!!!
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Get your 10mm wrench or socket and shove your arm in to the left of the trans dipstick tube and to the right of that heater hose and, unless your arm is very very fat, you should be able to get to it. I had to stop a couple times because of the awkward angle & my hand cramping, but I got it after a couple minutes.
It's one of those bolts that really doesn't get much easier to turn until it's almost all the way out, but pulling the ECU out slightly from inside the van as you go can make it a little easier. I should say here Don't Rock the ECU Right to Left (or up & down). Pull it straight out or you risk breaking off one of the pins. (ask me how I know)
Here's a photo to hopefully help someone else out down the road.

It's not a chip, it's a module that goes into the slot.
Unfortunately the module's shape doesn't fit through the hole so I have to open the ECU.
It's this one:
http://www.summitracing.com/parts/mvc-289821
On the Motorvation Homepage they say that on a 89 302 HO in a Mustang w/ Automatic they gained 22.5 HP and 25.6 ft/lbs on the dyno.
All I'm trying is to find a good balance between power gain and fuel consumption.
Meaning - I tune my engine so it takes less gas.
Dropped from almost 20l/100km (11.75mpg) to 16l/100km (14.68mpg)
So for the removal:
It means that the connector has no guide and it's just "plugged in"?
It's sad. I hoped that there is a similiar lock like I got on my BMW.
A locked lever that pushes the connector out while you pull it...
Cool, I'll have to look into getting that module myself. Not looking for a hot rod in this vehicle, but I do need a few more ponies to keep the speed limit on long hills.
The connector does have two slots to guide it in and ensure you don't install it upside down, but the only thing keeping it from falling out is that one 10mm head screw. I'm pretty sure even Popeye could shove his arm in there, you can do it.
Would you let me know how that module performs for you?
Because since the Van drove the last time, I installed an "Accel Super Coil" and wrapped the Shorty-Headers with "Thermo-Tec Exhaust Insulating Wrap"
One thing I should mention:
The Chip is ment for using premium gas
If I'm right it is 91 octane
Here in Germany the lowest octane fuel is 95 - so I'm good with this maybe I can set the Timing a bit earlier
And I don't suppose Germany is achieving those octane numbers with the use of ethanol. They're pushing that e10 crap all over the place here.
I'll bet you can get away with 14 or 15 degrees of initial advance with that primo fuel. At least.
The "Super" has 5% Ethanol in it and there's the "Super E10"
Both of them are 95 octane
A few Gas Stations offer E85 - but the raised consumption destroys the advantage in price.
And there are really f-ing expensive (ethanol free) "Racing Fuels" with over 100 octane
But that is just alibi-fuel for the "Formula 1"
They have the rule to race with altered Street Fuel - so as an example Shell came up with "V-Power" fuel
But Back to the Chip:

That's the one

On your Pic, I couldn't really focus where the bolt is.
I saw one - and of course it was a wrong one.
Couple of minutes later I realized the bolt is in the middle of the connector.
I took the ECU apart - to get to the port.
There's some kind of Wax or Grease on it.
And under it there's clear coating.
That all must come off.

The Case of the ECU needed a little trim

I haven't driven the Van yet.
I have to clean the windows first


