couple of thoughts...

- make sure you have the top of the air filter compartment securely fastened
- check that firing order
- make sure connections at both ends of plug wires (coil pack and plug) are securely fastened. I had one pop off at the coil pack end when I drove over some rough cobblestone roadway.
- if you clean the MAF do it when the MAF is cold (ie the truck has not run in a few hours)
- OverRover is one of the best posters here, huge knowledge, super helpful. I'm not going to flame him, but I've had very good experience with Kingsborne so reasonable men can disagree.
- ihscouts, that new avatar saddens me.

 

Thanks for all of this help. I fired it up this morning just for fun, and pulled a random misfire and misfire in 1, 5, and 6, which I think are all right next to each other on the coil pack. But, it's snowing and I needed coffee, so when I warm up I'll go back out and check the firing order and gaps.

Does it matter if the wires touch each other at all?

Anyway, this is Nashville's first real snow, and its killing me that I'm not out tooling around!

 

Doesn’t matter if wires touch. Now, if a wire was sagging real low and ran up against say, the exhaust manifold, and it burned through the wires insulation then you’d have a problem.

 

 

Ok, guys, I'm an idiot. I had the 6 and 8 wires mixed up on the coils. switched them, and it fired right up. ADHD--what can I say.

I did notice that it still missed a little under acceleration up a hill. It's MUCH better than it was, obviously, and is drivable. But still a mystery. I've got a fuel filter to install, and will clean the MAF--those were next on my list.

I cleared the codes, and will report back if something comes back.

At any rate, thanks for all of the helpful responses: sorry it wasn't something more exciting.

 

Still here Walt with all my Rover knowledge just happen to be fond of the original.

Like a middle finger!

 

Ok,

I'm back. The engine starts and idles as well as it ever has--it used to start rather hard, but now it fires right up. However, at any RPM level past 2500 +/-, the engine begins to stutter and misfire pretty dramatically (it doesn't back fire--just that "wump wump" that has always meant misfiring in my limited experience). Driven quite a bit since I last posted, but no CEL to indicate what might be happening. This was not the case prior to the plug/wire replacement (or, at least, not nearly the extent that it is now). Have I opened a pandora's box? Or is it possible that this is just more user error.

I have one of those WiFi scanners with an app on my phone--just installed it today. I've got a little bit of data from that, but nothing that I really know how to interpret. But if knowing engine load, MAF flow rate, etc., is helpful, I can post that too.

So, again, any and all help is appreciated. I can certainly drive around if I stay under 2500 rpm, but that means it now takes like 2.5 minutes to make it to 50 mph, so it's all surface roads for now.

Thanks!

 

Sounds like, at over 2,500, you are running out of fuel (dirty filter) or have a weak coil/coils.


Good deal & fair enough.

 

Ok,

Haven't had a chance to clean the MAF or change the fuel filter yet, but trying to learn how to use this diagnostic tool. What I've learned is that my LTFT for both banks is 24.22, which, if I understand correctly, is crazy high. My STFT for both banks is constantly moving--for bank 1, betwwen -18 and +24, and for bank 2, between -14 and +17 (these are approximate-ish--my free app doesn't store info, so I have to watch while I'm driving). Generally speaking, idle or coasting or braking gives negative values on both banks, and working under any kind of load moves into positive. Because of the misfire, I can't seem to get the engine above 80% load. But at that load, 2500 rpm, at either 45 mph or 70 mph, we're looking at 20-24% STFT on both banks.

Thoughts?

 

Ok, back again. Last night the Disco died as I pulled out of a parking lot. I killed the battery trying to get it started again, so had it towed home.

Started just fine this morning with a jump start. Currently showing a P0138, P1179, P1177, and P1316.

I cleaned the MAF--while cold--a couple of days ago, the check engine came on shortly thereafter. It ran pretty well, and then right before it died it starting missing again.

I think my route now is to go ahead and change the fuel filter, replace all of the vacuum lines, check for an exhaust leak, and then measure fuel pressure. Does this make sense?

Is there something else I should pursue? From what I've read, this doesn't necessarily mean that the O2 is bad--correct?

Any and all help appreciated. Thanks!