Alas I have another problem with the rover. I recently replaced the sparkplugs, but somehow stripped the threads on cylinder #1. I took it to a shop and they attempted a helicoil, but then put some sort of insert into it. Now I'm getting a misfire on cylinder #1 about every 1-2 seconds, and it shakes the car slightly, gets worse, then slightly better. Now here's where it gets tricky. It only happens in park, neutral, or drive/reverse WITHOUT load. If I back up or drive above 5mph there's no misfires. Driving on the highway or surface streets are fine, as long as there's a significant load on the engine/coasting.

Every other cylinder is fine, and theres no codes/flashing check engine light.

Usually I'd send it back to the shop, but the owner is out sick and already backlogged with other cars. I'm trying to fix this ASAP as I have a wheeling trip on Sat.

 

Out of curiosity, how do you know it is misfiring in one, if there are no codes? More for my information.

I had a similar symptom in a porsche 911, the issue was the spark plug was loose. Could that be yours? I am sure there is a fix, at least it is easy to access. I just spent 4 hours w mine doing spark plug wires, wish I had the relocation kit.

 

I have the nanocom. It shows a table of with each cylinder and which are misfiring.

I checked the spark plug and it was snug. I'm trying to avoid touching the spark plug or taking it out, in fear of having the insert come out or I damage the threads. When I stripped the threads I was only using my fingers, so I have no clue how I stripped them.

I think my next step is to replace the plug wire. I have an extra one laying around. I just REALLY don't want to deal with the coilpacks.....

 

What about trying a new spark plug first? Maybe it’s the wire, but a new plug is easy to try.

 

I think thats what I'm going to have to do. I'm afraid of loosing the insert or something else going array. That's what got me here in the first place . I'm not sure if the insert is affecting the grounding of the plug. Whats strange is I thought it would make it misfire at higher loads, but its not.

 

More likely it is the wire if you have a new plug in there. Time to do the coil relocation?

 

Definitely on my list! I need to fully fix my motor mounts so I don't put a dent in the hood. Again.... I'm going to run it this weekend and see how it does.