Yeah drove it for two days before tearing it down, but I distinctly remember it had no idle problems. Something could have happened to the sensors in the meantime though.

Added another video. I have a feeling it may be very revealing.

 

I'm wondering if any of the wires are FUBAR'd in the engine harness? It could be possible that during assembly, that one brittle wire did itself in....

It might be worth it to test each wire ....... O2's, TPS, etc.....

EDIT....

Going to drive my Magnum to work tomorrow morning and plug in my tuner to check the O2 readings to understand how much the O2 should fluctuate. I do recall on on UEGO years ago, that the values should immediately change when you hit the gas....not unless that Ultragauge is really slow.

 

I may step on a few toes but I'll go ahead and say it, I would not trust that Ultra Gauge to be super accurate and I certainly would not base my assumptions on what an $80 all in one gauge says. Dont get me wrong they are cool and can point you in the right direction but that's about it. Not bashing it, I know a lot of guys here have them and they are great little tools for the money. All I'm saying is there are far more precise ways to measure readings and values that may help narrow your search for the problem.

Sounds to me like something sensor related is pissed off but its hard to say what since you have a fresh motor. Do you have a buddy with commercial diagnostic tool that speaks Rover that could run a scan for you? At least if you have two similar readings from two different tools you'll know the cheap one isnt sending you on a wild goose chase.

Just another bump in the road man, those little bugs are always the biggest pain. Process of elimination though, just hang in there.

 

ET - the pix I sent awhile back of my cheap scanner shows a lower TPS position, like 9%.

I just went out and cranked mine, watched the el cheapo Actron scanner, and saw this just after cranking (scanner takes a short time to boot up, go thru internal POST, collect data, etc):

TPS - 9.4%
898 RPM (will drop to 700 when warm)
29% Calculated Engine Load
104 F coolant temp
70F Inlet Air Temp (under hood for me, the sensor won't fit inside a cone filter)
30 advance

Your TPS reading is higher, so that may well be a place to start. The TPS is an adaptive sensor, it compensates for mechanical wear of the linkage it is attached to. But as it is a potentiometer, sometimes the resistance track can become dirty or worn in key places from vibration, giving readings that are not smooth across the range of movements. There is also a baseline idle adjustment, but don't go there just yet. The key to making sense of readings is that they need to make sense. If the IAT says it is -40 F, and you can still feel your fingers, might be suspect, etc....

 

Thanks guys I'll respond individually when I have a bit more time.

I've been analyzing the video data, looking for clues and here's what stands out to me:

CAT F B1 S1: either ERR or 8711. Anyone know what this is?
Timing seems high
MPH is about 10% slower than analog gauge

Bank 1 O2 1 varies and drops from 1.020 to as low as 0.26, while Bank 2 O2 1 stays at 1.020
At the same time Srt Tr1 (Short term fuel trim bank 1) varies and drops from 24% to roughly between 20 and -20, while Srt Tr2 stays at 24%.

 

Well one issue is that there was no real baseline. You started with a totally unknown vehicle, did major repairs to the engine, but with just the two days of driving and ownership, you really do not have an established baseline for the rest of the systems that have not yet been brought up to same condition as the engine has.

You got old 02 sensors, old cats, and all the other sensors and interconnects.

If there is an ECU issue that is also compounding the problem.

Wish I had something more constructive to contribute. You are basically at the point of attempting to eliminate possible contributors to the conditions.

 

WARNING!!!!!BANK 2 O2 sensor is BAD!!!!!!!!!!!!!! This will cause idle issue! Its beyond full rich! You are washing your cylinders with fuel and burning oil.


Your sensors must change they are designed to go full lean to full rich as they take measurements.

 

Can someone here tell me which color wire their orange front O2 connector goes to? Want to make sure I didn't get bank 1/2 swapped...

 

here you go, looks like Right to me. Orange & green wire.

MPH digital vs the speedometer... there is a smoothing and signal processing board in the cluster that smooths that out. Raw data could be different. Mine does same thing. Tire size impacts.

But IACV is the boss of it all under idle conditions. If stepper motor not smooth, I bet ECM keeps trying to re-learn the position. I could not get mine to sync with ECM, ended up swapping ECM also. There is a under $40 IACV swap I believe.

 

I believe DiscoLife has given a good assessment of the situation.

Could be the original 02 Sensors in there. A new pair seems to be in order.