Hey all,

A few weeks ago I started the car and it was really shakey, knew something was off. After about 5 minutes started hearing a noise, its hard to describe but can't hear it in Neutral, just in drive and after 2k rpm, when I accelerate gets louder. Its not a constant noise, pops are louder and some are not as loud and definitely gets louder the higher the rpms. If I shift to neutral can't really hear it.

Got home and plugged the nanocom, had a lot of misfires, at idle would just go up and up. Had errors p1300, p305 and p300. Checked the spark plug which I had changed earlier this year and looked fine. Changed the coil wire for that one cyl (cyl 5). Started the car and there were no misfires at all in idle on the nanocom. Still felt a little shakey and looking at the roughness tab on the nanocom cyl 5 still constant 2/3/4/5 while others are at zero and once in a while shows 1 or 2. Nothing on the misfire tab. Took it for a drive around the block, at first no further misfires seemed fine however the noise was still there, only in drive if I switch to neutral I can't hear it. Noise definitely concerns me. I also got the car to misfire again, had a few misfires on 5 again, way less and iddle again no more misfires.

I plan on changing all the spark plugs and wires but any advice on what this noise might be? I need to go take a video of it and wish I could hear it in neutral but only while driving around. Could it be the cats?

Thank you all!

It could be a failing coil pack. Although each coil fires 2 plugs, I've known one car that was misfiring on only 1 of the two. Coil packs are easy to change on a GEMS but a bit of a pain on a Thor, you need small hands and a 1/4" drive socket unless you fancy taking the upper manifold off to get to them.

Another vote for coil pack.

Similar issue ages ago not seriously long after I bought the car. New set of plug leads cured the problem for a while but it came back in, I think, a couple or four thousand miles. New coil packs nailed it.

As with yours problem was mostly on one plug so plug leads were obvious first step.

Big worry these days is replacement part quality. So much China Inc stuff out there without rigorous quality control. Presumably paying the green oval tax is safe. I did due to wanting to minimise the risk of having to get behind the Thor engine again. My glove size 6 hands are small enough to get in there but it's still a right pain. I'll shift the manifold if there is ever a next time.

Double ended coils can be really weird.

Clive

Thank you Gilbertd and Clive 603!

I am just trying to do the easiest cheapest stuff first. I know that the coil packs were replaced before I bought the car, I have had it for about 15k miles so not that long ago, that said like mentioned parts quality is really poor now a days (have had some really crappy parts lately actually.

I was going to do a compression test next but maybe should jump straight to the coils.

My question is this noise I am hearing ( I will try to get a video of it soon). Its just really strange that only does it when I am driving, Neutral even rolling it will not do it, its pretty loud specially as rpms go up, if just rolling off the accel I can't really hear it. Sounds like different size tools are dropping or something. Got me really concerned if its a sleeve or of course the dreaded HG.

Thanks again I appreciate everyones help here

Have a look at the MAF readings since you have a Nano.
Last one I had go out made it look like coils and wires as well.

Bolt wrote:

Have a look at the MAF readings since you have a Nano.
Last one I had go out made it look like coils and wires as well.

will do that today, definitely worth looking into.

managed to take a video of the noise.

Like I mentioned only happens on acceleration in drive, neutral can rev as much as you want nothing. I was holding the brakes and accelerating to get the noise to happen, definitely less loud than if you go drive it but can clearly hear it. What do you think?

https://youtube.com/shorts/pAxOSxS3SWo?feature=share

Also checked MAF readings. Cold start was 44 g/s and after 10 minutes was 26g/s. This is pretty high right?

Car also is not loving to start, cranks a couple times before it starts. It is very cold today but I have noticed it had been not as quick to start even when it has been a little warm a few weeks ago

For the MAF, if you are using a Nanocom, it reads in kg/hr so 26 is a bit high but not by a huge amount. Spec says it should be 20 +- 3kg/hr.

The noise suggests it is running on 7, which you already knew, and it is the mechanical bits moving but not as a result of combustion. I've heard it before and it does sound nasty but will go away when all cylinders are firing.

Thank you so much. I truly appreciate your knowledge always!
So the MAF reads in kg/hr but on the screen says g/s? Maybe my nano is set up to grams/sec?

Since it seems pretty unanimous that this could be the coils, would it be smart for me to swap the wire from cyl 5 to 8 (cyl 5 is the one that is running rough) to see if the roughness/misfire moves to 8 and then know that its most definitely the coil?

once again, thank you!

Gilbertd wrote:

For the MAF, if you are using a Nanocom, it reads in kg/hr so 26 is a bit high but not by a huge amount. Spec says it should be 20 +- 3kg/hr.

The noise suggests it is running on 7, which you already knew, and it is the mechanical bits moving but not as a result of combustion. I've heard it before and it does sound nasty but will go away when all cylinders are firing.

Swapping the leads wouldn't be a bad idea to see if it moves.