280Z Stalls Randomly While Driving

[jjoconnor]

Hi,

 

Apologies in advance if I have missed a post with similar issues described: please link: 

My 280Z has been acting odd as of late. While out on a test drive, I pulled into a petrol station, but upon restarting the car, the car would start but would idle roughly (500rpm) and suddenly die after about three seconds or upon any throttle input.

I tried to start the car again a few more times while fiddling with a few things in between (checking fuel pump, checking grounds etc.) but after about an hour of letting the car cool down, the car suddenly burst into life and I was able to drive it home. 

Later that afternoon, after replacing the fouled spark plugs, I went out for another drive to see if anything had changed; it hadn't. 

Twice while at cruising speed, the car suddenly lost power and almost stalled (but managed to recover itself). On the third time the car stalled completely, but I was able to start it up fine and drive away.

I cannot perceive anything that would be causing these random stalls. However, I have been reading that the ignition module in the 280z is prone to overheating causing failure.

 

 Just before these issues, the water temperature guage also stopped working (could it be down to the temperature sensor?)

 

- I will be replacing the fuel filter asap

- Spark plugs have been replaced

- Fuel is not bad

- I will be checking the distributor and ignition coil soon

 

Thanks in advance,

Jethro 

 

[Zed Head]

The temperature gauge sender and the temperature sensor are two different things.

What year is your Z?  Does it have the original ignition module?  Original distributor?  What did the tachometer needle do when it was running poorly?  That's a sign of module problems, if it jumps around.

Ignition module or ECU seem likely, especially if they are original parts.  They're old.  But the distributor's pickup coil and the EFI and/or fuel pump relay are also possible.  My car had problems with three of those four, and I have found bad pickup coils on parts cars.  So, in total, I've seen all four (five) go bad.

[jjoconnor]

I was thinking that the guage sender and the temperature sensor were different.

The car has a 280zx engine swap. I am unsure what is original or not. I will take it for another drive, but from what i remember it didn't really jump around.  

I'll have a look at those parts you've suggested.

Thanks for the reply, I'll get back to you this weekend when I test again

 

[Zed Head]

Your failure mode is very common for the 280ZX "black box" ignition modules.  It's on the side of the distributor.  Get hot, fail, cool down, start working.

[jjoconnor]

5 hours ago, Zed Head said:

Your failure mode is very common for the 280ZX "black box" ignition modules.  It's on the side of the distributor.  Get hot, fail, cool down, start working.

Cheers, I'll insulate it and do a test to see if it randomly stops working. I reckon the issue is to do with heat. 

[Dave WM]

Next time you stop to get gas, pop the hood up while refueling (hot restart issue). Are you driving low on gas? hard left turn when low on fuel will make my car stumble (low fuel pressure from sucking air thru tank pickup).

ZH has mentioned a ign fix with a modern GM equivalent, I have not done the mod but lots have. Replaces the module used by the distributer.

[jjoconnor]

Finally got a video of the issue. No throttle was given until the car began to stall (as seen) checked ignition coil, fuel pump. 

I will put fuel filter in asap.

All guages are in view along with my feel. 

Car was completely cold at time of video.