brem

Hi there! Hope someone can help me...

For the past two months or so, my 1981 280zx (turbo automatic) has been dying on me when is gets up to or around operating temperature. After it dies, sometimes it starts right back up and other times it takes days to weeks for it to start again.

Here's what I've put in so far:
ignition coil
spark plug wires
cylinder head temp. sensor
power transistor

Here are some other torubles i've had, maybe they're related???
Before it dies, it will idle rough, bouncing between 1000 and 700 rpm
I've noticed it has poor acceleration before it dies as well
It also has occasional surges of power for no apparant reason

I'm thinking maybe the ignition control module, but i can't even seem to find it

I'm at my wit's end for what to do! Any help at all would be greatly appreciated!

Trex

Welcome to the site! When's the last time you did a tune-up? I'd check your basic tune-up stuff like spark plugs first. I'd also get a can of Deoxit or some other good electrical cleaner and clean all of your electrical connectors. They are usually pretty badly oxidized. I'd pay close attention to the connector for the CHTS, AFM, and injectors in particular.

This link here also sounds really similar to your problem so you may try some of the troubleshooting there:

https://www.zdriver.com/forums/showt...ts+down&page=2

Good luck and keep us posted!

Japedo

Have you checked fuel pressure when it stalls/doesn't start?

FricFrac

More likely the AFM and/or bad connection although a bad fuel supply (pressure, injectors) can cause similar problems. Rebuilding an unknown AFM is always a good idea - search the threads there is a link here to show you how to rebuild it. A good idea is also replacing the vacuum lines if it's a new to you car - they are cheap and you can get rid of some serious and some not so serious issues just by shot gunning all the vacuum lines.

Replacing the ignition transistor is basically replacing the ignition control module - the ECU sends a low level signal to the transistor and the transistor does the heavy work. If the transistor fails you're better/cheaper to replace it with and 4 wire HEI module. They are stuipid expensive for a power bipolar transistor. Main thing to do for the ignition is to replace the spark plug wires, cap and rotor and while you're at it you may as well replace the plugs with the NGK's recomended in the manual. Believe it or not they have proven themselves to be the best performing plug for the L28.

Deoxit is a great product. Kramlin is very good but I don't know if you can get it any more. You're really band aiding corrosion problems though which is why I put together a connector kit to replace corroded connectors. Corrosion comes back quickly since the plated material which resists corrosion is gone.

brem

Ok I will get out there and clean those connectors! And I was planning on rebuilding the AFM, I'll just put that on my short list then...
I'll also replace those vacuum lines. They do look cracked

I'll let you guys know how that goes!

As for a tune up, all I've done is change the oil, spark plugs and spark plug wires.

workingprogress

i had the same issue, i would check fuel pump relay, and the ignition control unit once those things get hot sometimes they start failing and wont let the car turn over until it cools down good luck

koprutzxt

i would say the ignition control modual , it tells your car when to turn on and when to stay on... located by the ingnition coil

Pipsqueak

I had this type of issues with my burb. Turns out the fuel pump was my problem.

Replaced it, and my issues went away,

FricFrac

The ignition module actually fires the coil. It uses a small control voltage from the ECU to control a large current surge required to charge the coil and fire it.