No oil pressure&engine dies

So today i pass the MOT (:)))
When i drove back home ( about 40 km/h) the rpm niddle start goes up and down and when i try to accelerate nothing happend. I notice that the oil pressure was zero(!!) After few seconds the engine just die. I was able to turn it back on only after few minutes.
Any thought were to start looking ?

1988 = Lucas ignition, right?

You’ve likely lost the coil (or the amplifier) temporarily - heat or bad connection.

I have to say that when the engine is cold there is no issue’s with the rpm, this only happend after driving for 20 min

IIRC, there have been listers with Lucas, who have had similar “hot” stalling issues - one of the ideas is to rule out the AB14 amplifier (which sits on the B-bank intake manifold) is to put an ice bag on top when the problem occurs. If after a minute upon the ice treatment the engine starts, would know where to start…

The more knowledgeable folks with Lucas ignition will chime in soon to help with other suggestions.

Good luck.

While the engine is running, wiggle the wires from the AB 14 amp that go rearwards toward the firewall.

How this should help ?
You think it’s a guage issue ?

One of those wires triggers the EFI. And it’s notorious for intermittent issues.

I had similar problems when i replaced the gm module in ignition amp, and improperly applied the heat sink compound. Car would run fine for about 10-15 mins, and then just stall.

If you’ve never replaced gm module, you should. $40 part that plays a very important part for Lucas ignition.

And ONLY buy GM/Delco brand.

I’ll start by replacing the ignition amp (lucas)
Do i have to buy the same lucas amp or i can buy any other brand ( any recommendetion ? )??

I’m also in the midst of replacing my amp, inside the AB14 (Lucas) there is a GM part, as Greg wrote above, which can simply be swapped in. I’ve tried two aftermarket amps, both which overheated almost instantly, so I have to agree with Greg - only buy GM or Ac-delco, the part-number for the Delco is ‘D1906’!

The Lucas amp is the whole unit. You only need to replace the module. I would recommend buying your own heat sink compound. What comes with the module is not the best, i have found.

Greg, this is the part i should buy ?

Yes it is.
Good luck.

Searching around Amazon, eBay, and elsewhere shows the same part has a large range of alternatives for many different vehicle makes. We can only guess which ones may be better than any other, considering what is available in your locality. But I’d figure that a modern part, for any applicable vehicle, is likely to be more robust than what would be current 25+ years ago for our V12s.

Yep, just be sure it has GM or AC Delco imprinted on it. You don’t want a no-name being posed as GM.

I got mine from summit racing, $37, it was the real deal.

I just replace this ignition modul but there is no change in the car low oil pressure. Those this Amp should be so hot ???

Does the engine run? Are you hearing a lot of clatter from the engine?

The HEI ignition module does absorb some energy in the course of its duties, and because it is so small that does cause it to get pretty hot. That’s why it needs to be installed in the AB14 case with thermal conducting paste, and why the AB14 is bolted to the intake manifold – a large, air-cooled heat sink.

Like this right ??

The module makes no difference to oil pressure.


No, still very low pressure once the engi e is hot