Nissan Caravan 1996 Randomly loosing and regaining acceleration. NA20s 2l Manual

[Chris]

Hey all! Would very much appreciate some advise and help on this one. Ive been battling her for a little while now and not making much progress. 1996 Nissan Caravan NA20s engine. 2l petrol carby model. 244xxxks. Manual transmission.

Videos of the issue: (Can clearly hear the exhaust and see what is happening here)

I have been randomly loosing acceleration, some days its perfect and others I barely make it down the road.
Seems to be happening to me more frequently now, I can drive for 5 minutes without an issue and it suddenly feels very lacking in power, and decreases until I am pulled over and stall. On a good day I can get 30mins into a drive before it happens. It barely runs in low rpm and gets worse with higher rpm’s. When it happens, I cant seem to get it to run clean. It doesn’t smoke much when it happens, and the sparkplugs appear to be in normal condition.

Temperateure doesn’t appear to be a factor, as it happens both when its cold and when its been running a while. My current fix for when it happens is to pull over and turn it off, wait 5 minutes and get going again until it happens again.

I have tried replacing the in tank fuel pump, new spark plugs, coils, ignition module, had the base timing adjusted, fuel pump relay looked at, and have a new air and fuel filter. Cleaned dizzy points too.

I however haven’t yet replaced any other relays, replaced the ignition barrel, or cleaned the carby. These are just other thoughts I have come up with.
Not sure if it has an O2 sensor or Cat converter I need to look at. Any advice or if you have had a similar issue, please put in your 2cents!

Where should I start now? I am anxious to pull the carb apart as it is different to the classic motorcycle carbs I am used to. The videos above show the issue pretty clearly, but I am running out of time and money to sort this out.

Topic

[Chris]

My mechanic adjusted the timing and played with a bunch of vacuum hoses. My plugs are now pitch black of dried carbon. Exhaust is leaving a black mark on the ground. Super rich it appears.
I want to test my Cat converter, can I unbolt it loosely and release the pressure (assuming its blocked) and see if there is any performance change?

There is an 02 sensor both before and after the cat.

[Rahul Jones]

When this happens does the engine die out even with the clutch depressed?

[Chris]

Yes it stalls with the clutch engaged or disengaged. I’m currently stranded on the road side, super spluttery and huge loss of power. Headlights dimmed as it began to die.

Ignition relay and fuel pump relay?
I was thinking of ordering a second carb tomorrow to bolt in, expensive way to rule out the fueling as the issue

[Author]

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