View Full Version : Cross Threading Spark Plug


Scoot RX-8
11-14-2009, 02:16 PM
I think I have inherited someone else's problem!!!

Decided to change the plugs in my 8 this weekend. When I tried to pull the old plug in the Lead of the first rotor it was a son of a bitch to take out. As I was taking it out it was getting harder and harder ... I mean my hands are soar from working the ratchet! Everything looks normal.

When I tried to put in the new plug ... it starts to go in crooked!! I can't get the plug straight for the life of me! It is totally screwed! (pardon the pun!). No matter what I try I cannot get it to go in straight.

I can't fix this! Anyone run into this before? Did you have to put in a thread coil? Dam! I was just doing this before I stored it away!! Son of a Bitch!

Can anyone help?

ZmFnZm
11-14-2009, 08:38 PM
OUCH that sucks! i got nothing on this sorry

b'Eight'
11-14-2009, 09:05 PM
Go buy a tap and run it through the splug plug hole to clean the threads out. Please make sure you GREASE the tap in order to catch and prevent any metal chips from falling into the hole. You should be all right.

Worst case scenario you will have to re-tap the hole and put in a helicoil with a spark plug fix kit ($20).

AJ's Shinka
11-14-2009, 09:41 PM
^^^+1 I have had two friends crossthread their spark plugs and I went to the local autoparts store to buy them a retreading tap/tool to re thread it for them. Go slow and careful, and you will be alright... make sure you get the right size bring the spark plug with you. Good luck.

Scoot RX-8
11-15-2009, 01:18 PM
Got a rethread tool and got the plug in!

The reason for the new plugs is that I have been having problems with hard starting lately and since colder temps came around I thought perhaps it was flooding. Last time I ran it I made sure it was well warmed up before I shut it off. I left it for a couple weeks and got new plugs and wires thinking it would be good to fix this issue before storing it away.

After everything was back together, the car will turn over, but no spark it seems. I have not tested for spark as I ran out of time. I know all the new wires are connected properly!

I had 4 new coils replaced in the summer by Al's team (sniff, sniff ... gonna miss you Al!). No error codes. Fuel pump is running. Not sure what's up. I will have to check for spark later on. What could I check before the coils?

@!!narotordo
11-15-2009, 01:47 PM
^^^+1 I have had two friends crossthread their spark plugs and I went to the local autoparts store to buy them a retreading tap/tool to re thread it for them. Go slow and careful, and you will be alright... make sure you get the right size bring the spark plug with you. Good luck.
That was not fun but I'm good now thanks to AJs mad skilz :ylsuper:

nate340
11-16-2009, 10:27 AM
hard starts usually coils or low engine compression.
hard starts are how i ended up with a new engine

Huey52
11-16-2009, 10:36 AM
Well done. Now, I hope [apparently unlike the original owner] you used some anti-seize paste on the new 'plug threads.

Even tho' you believe the coils are good, do an inductive test on them (timing light) which will also verify the connectivity of the cables. Also a resistance test on the coils. See encl.

Also be sure the coils-'plugs are in the proper timing order.

Got a rethread tool and got the plug in!

The reason for the new plugs is that I have been having problems with hard starting lately and since colder temps came around I thought perhaps it was flooding. Last time I ran it I made sure it was well warmed up before I shut it off. I left it for a couple weeks and got new plugs and wires thinking it would be good to fix this issue before storing it away.

After everything was back together, the car will turn over, but no spark it seems. I have not tested for spark as I ran out of time. I know all the new wires are connected properly!

I had 4 new coils replaced in the summer by Al's team (sniff, sniff ... gonna miss you Al!). No error codes. Fuel pump is running. Not sure what's up. I will have to check for spark later on. What could I check before the coils?

Scoot RX-8
11-16-2009, 07:52 PM
Anti-seize?? Dam right! I will never put plugs in without it, now that I have went through this crap!

Thanks for the coil check document! I will follow this on the weekend!!

Much appreciated!