Could be, or could not be. Even with it running poorly that still will give you an indication. For example, you can expect O2 readings to be erratic, but O2 won't cause this because the ecu doesn't even listen to them when the truck first starts. On the other hand, erratic running won't throw off cam sensor readings or MAF readings that much, or at least you can expect how much it will throw them. You're looking for extreme outliers.

 

Bank 1 downstream showing 0v, FuelSYS1, FuelSYS2 fault.

 

Found this thread after searching fuelSYS1 fault. Symptoms are virtually the same. All this for coil packs!??

https://landroverforums.com/forum/di...-mayhem-51416/

 

Finally got some time to get under the hood. My plan was to check plug wire connections at the coils and the loom connections to the coil packs.

Here is my possible egg on face confession. While removing the intake plenum I noticed the first bolt wasn’t particularly tight, it was more than finger tight for sure but I wouldn’t say that I had to break it loose. The rest of the bolts were pretty much the same, best way to describe the tightness is that they were snuggled up. There was no play in the plenum or anything but there is no way I torqued them down when I was finishing assembly after the HG job. I haven’t put it back together because I have a new coil pack coming tomorrow. The plenum gasket was pretty wet, almost dripping with a mix of oil and gas.

Could this oversight in reassembly be the cause of my misfires?

 

Could be, but I’d go back to the coils. I’d also be checking heavily the intake boots for leaks and such. As said, brake boost issues say you have a vacuum leak somewhere.

I’d be doing some Seafoam in the intake, and I’d run a couple bottles in the tank as well.

 

I heard someone say seafoam is for idiots

 

It's nothing magical, but it is a pretty good cleaner. Sounds like someone who's a bit too confident and vocal about things they don't know anything about.

 

Maybe the float is stuck. Maybe it's the points gap.

 

You're just messing with us now.

 

I still have a dwell/tach and a timing light. Plus the feeler gauges and the file to use on the points. Just hanging on to them for when I finally get that '53 Chevy pickup. And the last carb I rebuilt was on a chainsaw a few years ago.