So I fired up my '82 Turbo, with the new '88 Z31T ECU today. I don't have the smaller 17mm O2 sensor installed yet (I'm actually having trouble locating a bung for that). It started up ok, and despite a bit of idle bounce around 1k rpms, it seemed fine. However, after a minute or so of idling and light revving up, the idling suddenly started becoming sputtery.

Yes, I did install the resistors needed for the '88-89 ECU, and I was still getting full fuel pressure. Is there any way to confirm the injectors are firing properly?

Even though the O2 sensor isn't installed yet, that shouldn't cause it to sputter and threaten to kill the engine, right?

The other culprit I might suspect is the "air regulator". I don't know exactly what that does, but from the looks of it, I suspect it affects idling. When wiring up the new ECU, the spreadsheet NismoPick had made said that pin 16 was for the air regulator (to be swapped with pin 108). However, I read somewhere that on the '88-89 ECU, pin 19 was the air regulator instead. I tried looking in a Z31 manual but couldn't get confirmation on that. I also tried connecting a multimeter to both wires to see if I got a (+) or a (-) reading, but I got neither (at least with the engine off). Does anyone know how to tell if the air regulator is working, or how to electrically test it? I wasn't getting any voltage to the connector at the air regulator with the key in the On position. Does the air regulator just take a regular 12V power source, or does it have some kind of voltage range, like a sensor (thinking about jury rigging if possible/necessary)?
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I believe the "air regulator" you speak of may be the auxillary air regulator used by the cold start system. I have removed my cold start system and the regulator along with it. I don't think this is your culprit if the sputtering is occurring with the engine warm.

 

no cold start valve/setup on turo motors, they use a fast idle.

 

i have the bunge adapter if you want it

 

Yes! I'd really appreciate it! Shoot me a PM when you get a chance.

I started the car up again tonight, and I don't know if it's the same problem as previously described, but when I quickly step on the gas pedal, it causes the sputtering, where the engine threatens to die. Yet, if I gently ramp up the rpms, it won't sputter. Is this caused by the lack of an O2 sensor and the ECU throwing in a whole bunch of fuel? Or is this being caused by something else, you guys think?

 

Can you rev it fine till it warms up? Might want to start w/ the air regulator wiring. Also check the MAF wiring & TPS. I'll do some wire tracing over the weekend on the 88-89 ecu, as I'd like to know too.

 

Are you using turbo injectors?

 

It's an L28ET motor... so yes, he is.

 

any update on this?

my 82 is doing the same thing.
i just installed a 87 set up.
it is really annoying.

idles great then rev it and it cuts out randomly and very often.

any help
thanks
tony

 

After installing the O2 sensor, that fixed most problems. I still need to have the gas pedal stepped in a bit while cold starting to keep the engine alive; I've already adjusted the throttle body open as far as I can while keeping the idle around 1000 rpms, but there is still some slight fluttering of the rpms at idle. Otherwise, once I get going it drives fine though. I'm going to wire up the fuel temp sensor shortly, so I wonder if that might help too.