Misfire/Low Compression Cylinder 8 - Recommendations?

cja89

New Member
Apr 15, 2018
9
2
3
29
Utah
#1
A few weeks ago I had the CEL come on with code P0308, but didn't notice any change it how the engine was running. I did some research and thought it was probably a plug or the ignition coil. I replaced both but the code came back. I checked the new plug and it looked slightly oil fouled. I ended up taking it to a local shop and they ran a compression test (wet and dry) and found the following:

1 - 145
2 - 150
3 - 142
4 - 138
5 - 145
6 - 140
7 - 110
8 - 80

They also stuck a camera down in and said cylinder 8 looks all black and gunky. They said they'd recommend just replacing the engine and quoted 4k for the engine and then 800 to 1500 in labor.

I'm thinking I'll try running some seafoam through a vacuum line and see if that helps anything. It's only had a noticeable misfire twice in the last few weeks and other than that it will occasionally idle a little rough. I'm looking for any recommendations on how to move forward. The engine only has 171k on it and I've only had it since May so if I can avoid an engine swap I'd be much happier than I am at the moment.
 

cja89

New Member
Apr 15, 2018
9
2
3
29
Utah
#3
Here's an update. I'm still driving it, but I took it to the place I purchased it from for a second opinion (and they said they'd figure out what it was at no cost to me). They came to the same conclusion and even went as far as removing the intake manifold.

As I was talking to the mechanic supervisor when I picked it up, he said "so this is what the 3rd engine in this?". I had no idea what he was talking about. He went on to say that he had only been working there for a few weeks, but his mechanic mentioned that they had replaced the engine in it before they sold it to me. Nobody from sales was there so I went back the next day to figure out what was going on. The guy I bought it from told me "I sell so many cars I can't remember everything about all of them so talk to my brother." (It's owned by two brothers.) Well I go talk to the brother and he tells me he doesn't think they did that, but he doesn't remember either...he's just "pretty sure". Then he tells me it was his sisters car from brand new. The actual mechanic wasn't there so I couldn't bring him in on the conversation. I tell him it sounds really weird to me that his mechanic would know the engine was replaced AND it was his sisters car, but apparently they knew nothing about the maintenance on it or if the engine had been replaced. They just kept playing dumb so eventually I just left and asked for a second time for a quote for an engine. It's been 4 weeks and still no quote after talking with the mechanic a 3rd and 4th time and him telling me he would send one over. It just makes the whole situation seem more suspicious to me.

I bought it as is, so I'm assuming I don't have any legal ground to stand on. The only thing I can think of is if they told a "half-truth", which would be that they advertised it and told me they had "just replaced the timing belt and water pump". That sounds like a half truth to me if they did that on a used engine that they then dropped in. I'm just not sure how to proceed from here except cut my losses and once it starts running really poorly to swap the engine out myself.

Long story short, I went against my better instinct and bought from a used car dealer which I will never do again.
 

Sal R.

Active Member
Apr 6, 2017
311
142
43
San Diego
#4
Sucks to hear, bro. If the HG is blown, chances are it overheated and/or was not maintained properly.

Blown HG is just the beginning.
 
Mar 28, 2018
93
6
8
#5
Yeah man sorry to hear. It seems like it might be better to just part it out and get a new used one.

If your weatherstripping is still in good shape, you could sell them individually and probably recoup half your vehicle costs. Haha
 

cja89

New Member
Apr 15, 2018
9
2
3
29
Utah
#6
Well...it ran well until we were on our way back from Montana for Christmas. Somewhere around Idaho Falls I noticed the check engine light started blinking for 30 seconds at a time and would then go solid for a bit then blink again. As soon as we took our exit in Utah, the engine was running rough unless I was on the gas. I got it home and parked it. Checked the codes and it had p0300, p0301, and p0308.

I ended up selling it about a month later after I bought an 05 Limited with ~148k on it for a great deal. I swapped the seats and a few other miscellaneous things that were in better condition on the 06 and called it good. It looks the exact same so I'm pretty sure most people don't even know it's a different one haha.