I get P1316 as well eventually.

 

I plan to go ahead and grab some more new plugs, also order a ScanGuage and 2 new O2 sensors.

Have any of yu guys run any of that CAT cleaner type stuff thru yours? I saw on HP TV today that Eldebrock is now making and selling all sorts of stuff like that.

They were taking a Mazda pickup which is basically a Ranger and swapping out the 4 cyl for a crate 302 with the new tubular mounting cradle and tubular front steering links. It was awesome, sorry for the HighJack.

 

You just got plugs Danny. Why new ones?

 

My thoughts and suggestions....

Check your fuel pressure and volume. A clogged fuel filter or faulty pump can give you a misfire.

Revisit your crankshaft position sensor.

Typically on engine reasssembly the reluctor tabs get bent when you tighten the 4 torque converter bolts. (I would be looking in this area for problems)
You MUST scope test this sensor to properly diagnose it or rule it out.
Any single trace scope will work. It's an A/C voltage signal and must have at least
+/-5V spike/waveform signal. factory spec between 6-10 vac less than +/-5 VAC wave form would indicate a bad sensor or the sensor is not deep enough in the reluctor to be read properly. Any excessive voltage spike or weak spike would represent a bant reluctor tab, or possibly a loose relutor ring or rivet. You are looking to backprobe terminal 12 on ecm connector 1033.
(IIRC it's the smaller black plug on the ecm but make sure using your aplicable wiring diag in RAVE)
Measure using scope settings 12-20 Volt AC 2ms div. You can change the volt range and m/s div to widen or shorten the height or length of wave signal.

If you find nothing with the ckp, reluctor, fuel pressure, I would suspect a (or many) stuck exhaust valve(s).

You also have to remember that you have eliminated the catalytic converters on your vehicle, and that it was/is designed for NAS market. Even though You or I may think the vehicle would not set a code for misfires because it has no cats it may. I would suspect you would see a catalyst efficiency fault code before a misfire code but anything can happen.
You could try disconnecting all 4 of your OX sensors and see if your code resurfaces (along with 4 sensor codes).

Your last option is swapping a know good ECM into your vahicle. There is always the possibility that the ecm has been fried when someone welded the exhaust system.
You will never see this if you open the ecm and look at it. It can be as shiny and new looking as you like and still be fried...

When swapping a known good ecm in to your vehicle, you will need to relearn the security immbolization using approved diagnostic equipment (T4 or equivalent).

 

Fuel pressure was 38 PSI engine off, ignition on, last check. Fuel filter was replaced already.

I've inspected the reluctor area extensively but will revisit it if the new CKP doesn't fix it. Thanks for the scope test advice. I will surely be doing that if all else fails.

Valves are a possibility if the new rocker assembly was screwed up somehow.

Since the misfires have been present before all changes to O2 and exhaust, I have to conclude that it has nothing to do with them. Though, it could be that the ECU is flawed from the beginning.

I thought the new CKP would be here this last weekend, but it looks like it'll be here today instead. I'll be sure to post an update then.

 

Mine keeps running rich, probably needs new O2's. But i wanted to throw in fresh plugs just to get a little better mpg for now. May try the NGK's that are on sale.

 

New CKP arrived today. Promptly installed it, went for a test drive, and I quickly noticed it seemed smoother. Drove around for much longer than it took before and no codes! I think that was it! Wow

 

Praise the Rover gods and pass the Lucas!

 

Here's what the Lucas one looks like inside.

Hard to tell what was wrong. The wires are very small.

 

That wasn't the Lucas I was talking about (Lucas Oil Treatment) lol -

But your pix shows two things. First, the tip can't be bent or covered with metal filings (your's is not). Second, being a coil of small wire, it is soldered or connected somewhere to larger wires. If solder joint is "cold" you would have erratic performance that would be heat related. If a mechanical joint, then temperature could expand that as well. A solder joint is also subject to cracking under vibration and stress. Another fun thing with fine wire is that it is actually insulated with a coating, like varnish; and such material has to be stripped away in the fabrication process to solder the wire, etc. If the wire supplier changes, the thickness of that insulation can change, and equipment set to automatically handle thickness "X" may not do well with thickness "Y". That assumes these are not hand fabricated, but instead made thousands at a time by machines built to do this.

Could you read the resistance of this coil with your meter and post that? I wonder if it changes if you tap on the unit, etc. A momentary open, or a partial short would change the performance of the pickup coil.