Turbo ECU's

[MrwassmanNA2T]

Here is the Scenario.

85NA Chassis, 9:1 engine, wire Harness, stock 5 speed.

86T Auto/ Non-federal ECU + Dual feed injectors

85T manual/ Federal ECU

I was running the 86T ECU out of my parts car. Pretty positive the wiring harnesses are different. I am pretty sure it would take a decent amount of work to re-pin/re-wire the system. I am pretty sure it has never been into closed loop due to the 02 pretty much missing out of the picture.

So i decided to pick up a 85T ecu. Found one, bought it, and installed it. CAR runs like garbage. Was running ~OK when i first started it and waited for it to warm up to were it sounded like the enrichment for warm up went away.

Started to drive away, seemed fine for about 30 feet. Then BOGBOGBOGBGOBOG. Let off the gas idles at 500 and dies. Try to restart, does the usual up to 1100 rpm and then back down to NO rpm.

Managed to get it back into the parking spot. Tried restarting it and messing with the gas pedal. Just smelled like extreme amounts of gas. put the 86t ecu back in and called it a day.

Can someone please help Much appreciated

[Jason84NA2T]

SO how did it run once you put the 86t ecu back in?

Did you double check the year of your "85t" ecu?

[MrwassmanNA2T]

It runs just fine with the 86T ECU.

And yes, it is an 85 Turbo Federal 5 Speed ECu according to its case numbers

[MrwassmanNA2T]

No help from anyone? Should the car run?

[homestar]

ok, i had a similar problem with my NA2T. Unplug the harness that connects to the FICD/AIC. It won't want to idle when cold, and then when it warms up it'll idle really low, like around 500 RPM (until you do something about that).

Basically all of the harnesses on that idle control garbage is different. I never bothered figuring out how to rewire it, I just stuck a cork in the FICD and plugged up the charge pipe.

If you monkey with the FICD settings enough, you'll get it to idle way high, up to like 2k, then it'll back off down to maybe 200 RPM, it'll sputter there for a few seconds, then shoot back up to 2k.

[MrwassmanNA2T]

So you did the whole TB idle setting?

I already wired the A/C part of it to a "Cold" idle up. Works well.

Maybe i can wire the other half to have a switch as well? Double as a Theft deterent.

What do you guys think?

[homestar]

MrwassmanNA2T wrote: So you did the whole TB idle setting?

I already wired the A/C part of it to a "Cold" idle up. Works well.

Maybe i can wire the other half to have a switch as well? Double as a Theft deterent.

What do you guys think?

don't waste your time. do the TB idle setting... as much of a royal pain in the ass as it is.

I didn't do that btw, i just keep my foot on the gas at stoplights. I'm thinking about making a manual idle control valve to replace the AIC but i havent had much time to work on the Z lately.

[MrwassmanNA2T]

I just re thought this, and it wouldn't be that because it runs "rich" even when at 1/4, 1/2/,3/4 etc. throttle. I am pretty baffled on the whole subject

[OR-Zman]

MrwassmanNA2T wrote: It runs just fine with the 86T ECU.

And yes, it is an 85 Turbo Federal 5 Speed ECu according to its case numbers

Am I missing something here? Why not ust the 86T ECU then?

One thing I am bebining to believe basesd on my own personal experience and thos things postd over time is thhis: The 84/85 electrical wiring and the 86+ electrical wiring just wont work together. :shock: Not to mention digi and analog.

Stick with the ECU that works for now man, you sanity will thank you. :?

[zmech]

z

[MrwassmanNA2T]

Yeah, shouldn't my 85na wiring be more similer to 85T wiring ? Not 86 T?

Fuck, well today i'll print out wiring diagrams for all three cars and compare the son bitches.

[homestar]

i have an 87 N/A wiring and an 84T ECU. Disable the FICD, and go from there.

[MrwassmanNA2T]

Wait, what is the FICD again ops: ? I know i know.

This is not the IACV is it?

[homestar]

MrwassmanNA2T wrote: Wait, what is the FICD again ops: ? I know i know.

This is not the IACV is it?

ok, it's that crap right in the middle of the upper intake plenum right smack in the middle. Just disconnect that whole harness and stuff a cork in the hole.

That'll fix her right up.

[MrwassmanNA2T]

I traced some shit from alldata. It shows the harnesses to be the same. I will try what you said. But it still baffles me on why it will work. (+ my wires are soldered on there so i have to get the gun out.)