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1986 Nissan 300ZX - Looking for help with engine

Hi guys I love your podcast and have laughed at many episodes like a crazy man and my coworkers think I’m insane. Any who, I have a 86 Nissan 300zx the engine was rebuilt properly from ground up with bigger pistons new bearings new everything basically… car had no problems and I was issuing it until last summer I drive it only summers and it started choking at stop signs or when I suddenly increase the speed it shuts off at stops and starts right up after now I have idle issues I can’t seem to hone the idle so it would keep the engine on. Engine shuts off soon after starting. I took the spark plugs out and noticed carbon build up on all. No oil on the spark plugs compression test is low on one cylinder but most are 130-140 cylinder one is 100. I have a new o2 sensor which I wanted to put in and I think it might remedy that. Please guid me with your expertise. Thanks

Ok, I am doubting that statement because of this;

One cylinder is 30% low, that is going to drag your idle down quite a bit. So can a bad idle air control valve (IAC). The O2 sensor is NOT going to remedy a low cylinder reading but it might help the sooty plugs.

The idle problem might be caused by a bad Idle Air Control valve.

https://www.rockauto.com/en/catalog/nissan,1986,300zx,3.0l+v6,1209563,fuel+&+air,idle+air+control+(iac)+valve,6072

Tester

You can forget that engine built properly scenario. The compression is way too low on all cylinders. It should be in the 190 PSI range.

You need to revisit the issue of who built the engine…

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