Hey guys, I have tried searching but I only found 3 threads with P0301 tagged (usually P0300) so I really apologize if I missed this thread somewhere.

I drive a 2004 6MT Coupe, and everything had been great as of late. Saturday night the car drove fine and I parked it in the warm garage overnight. The next morning when I started it up the idle was rough. I tried resetting the ecu and idle and all of that. Upon driving, my check engine light blinked upon decent acceleration and the car shook all over the place as well as being really down on power. I pulled the codes and received P0301 which is a misfire on cylinder 1.

My car is at 92,000 miles (haven't replaced the spark plugs yet). The battery is old but is being replaced soon (different issue, should be non related, but need new battery).

What do you guys suggest doing? I am pretty tight on cash as of right now, have a lot of health problems going on in family right now. I checked oil and there is no water or blue residue in there, but I am performing a compression check tomorrow just to check on that (previous owner kind of abused the car so I try to check the compression somewhat often). What do you recommend after that? Start with plugs?

Thanks so much for your guys' help! I am just really trying to keep her running great but I don't want to overspend at a stealership.

 

^ and the three threads I found were pretty much unrelated or unanswered. Thanks!

 

Bet you your injector is stuck. Start it and listen to it though a long screw driver . Should have the same rhythm as the others. If not, with the same screw driver, while running, tap the injector with the screw driver being tapped by another screw- driver,please, not a hammer. A nice love tap, you'll see, it will place itself. Been there, done that at our dealership...................

 

Pull your coil packs to check for oil in the plug boot. Your valve cover seals might be shot.

 

So I had the compression check done today and sadly the first cylinder's compression is way below spec (which is extremely frustrating). They are suggesting a new engine. Do you have any good sites you recommend for that? Besides classifieds here. Also anyone have experience rebuilding these?
Thanks so much for your input guys!

 

What were your numbers across all cylinders?

 

Compression checks should be done as a comparison of all cylinders vs a single cylinder and a known spec.

Usually if all 6 cylinders are within a certain window, you are typically fine. It's when a single cylinder is 20-30% lower than others that you have an issue.

So with that said, what were your numbers for all 6 cylinders.


In your case, I'd start with simple diagnostics here. Move the spark plug to a different cylinder and move the COP to a second different cylinder. Erase the code, go for a drive and see if the problem follows one of the moved component.

If the misfire swaps to the cylinder you moved the plug to, replace the plug. If the issue moves to the cylinder you moved the COP to, change that. If it stays put, it may be mechanical.

Start with that before getting worried about a more serious prob. If the shop is recommending an engine, have they pulled the head and confirmed it's not a popped head gasket rather than rings?

Having done a compression test, I assume you pulled the plug. How was the gap? Any oil in the spark plug tube?

 

Besides cylinder 1, the other 5 cylinders were between 178 and 182. Cylinder 1 was apparently 50 psi. I brought the car over to my brother's garage. I have to go out of town this week, but next week I will be performing a compression test myself as well as adding a little oil to the first cylinder and seeing if that raises the compression. After that were gonna check around and see if its rings or head gasket.

I am guessing since all other 5 cylinders have great compression, that it is not a head gasket issue? That would most likely affect 2 cylinders at least from my experience.

I didn't have time to perform the check this week inbetween work but I will work on it next week and I will let you guys know what happens! Also will probably have to ask for more advice/help.

Thanks so much guys!

 

Hi guys, so I finally got to take the car apart and perform the test myself and I got some surprisingly great news! As well as extremely frustrating haha.

So the dealership told me I was around 190 on every cylinder except for cylinder 1 (the misfiring cylinder). I performed the check today and could see they never performed the check at all. First of all there were no signs of them getting under the engine cover and doing any work (and they came back with the car very quickly). The manager of the service department pulled me into his office and said cylinder 1 was at 5 when it was supposed to be at 190 (yes 5, I actually have the paperwork for it, I mistyped it up above). They then charged my around $130 for diagnostics and compression check. Then he told me with a compression on a cylinder that low, my engine was done for and I needed a new one. He said through nissan installed it would be about $4000 but he would look at local junkyards for a new engine.

Long story short they never did the compression check and lied to me and tried to get me to buy a new engine. Any suggestions on what action I can take with them?

I will first be replacing the spark plugs to see if that solves the misfire on cylinder 1.

My compression test came out to be:
Cylinder 1: 195
Cylinder 2: 195
Cylinder 3: 190
Cylinder 4: 195
Cylinder 5: 175 (concerned about)
Cylinder 6: 190

So Cylinder 1's compression is fine. I added a little oil to cylinder 5 and the compression jumped up to 190. But then I did the same thing to cylinder 4 to compare, and that cylinder jumped up to 210 (so they both moved up 15 with the oil added (wet test).

What do you guys suggest in terms of cylinder 5? I would usually think worn rings since the compression went up with oil, but at the same time, cylinder 4 jumped up too and that compression was normal.

Sorry for the long post, I would appreciate any help or suggestions you guys have! Also I will be ordering spark plugs tomorrow, was looking at NGK, but if you know of a better brand let me know!

 

NGK, All the way. Amazon usually has the best deals on them.

 

NGK for sure. also swap coil packs with a known good coil pack and injector if you can't hear the pulse just to be sure. those compression numbers are not so bad. sorry to hear about the dealership problem. anything for a buck it seems.

 

I went with NGK platinums. I am either going to be fixing or replacing my valve covers while I have it apart (have a little oil in the plugs, not much).

Any of you guys have any idea why all my cylinders gain compression with just a little oil?
Thought it was a ring issue on 5 causing the low compression (still within the 25 difference recommended) but not too frightening. Just trying to think of why that cylinder is a little low.

 

Spark plugs changed and the engine runs just like it used to.
Went back to Nissan service department and showed them the car was running fine and asked for a refund because they obviously never did the compression test.
Service Manager demanded to do a compression test on 1 to prove it, we did, I watched him do it. Cylinder came out 150 on their gauge (Not the 5 they told me). So I got my refund (and some coupons but its not like I will be going back there), I usually never go to the dealership or shop but I wasn't able to check it for awhile. Lesson learned!