Running rough...wanted some pre-diag thoughts

We may earn a small commission from affiliate links and paid advertisements. Terms


...has a job!
So my car is running like dog shit and before I tear it apart I wanted some feedback. I recently did two things: put Sea Foam in my oil (eeek) and pressure washed my underhood...both within about an hour of each other. Now, it runs great for about 8 minutes until it warms up then it runs on 2 or 3 cylinders at low rpms. After 3500ish the 3rd cylinder kicks in and the 4th around 4200. Otherwise it sounds and smells like a chainsaw.I'm thinking I fouled the plugs with water or the Sea Foam. Oh and ftr car is a '95 EG w\ LS swap...nothing else special...I'm at work on my phone trying to post this so forgive my breavity.


Well-Known Member
yeah its something with the spark or injectors for sure. im thinking water got to it somewhere


...has a job!
So, 1 can of wire dryer, four NGK platinums, a packet of anti-seize and a packet of di-electric grease and everything is fine. I pulled the old plugs last night and they were all wet. There was a good amount of water in the plug tubes as suspected...

labe lincoln

New Member
kinda sounds like a blown head gasket. when you washed it the water should evaporate soon enough and be fine. you could have fouled a plug though. replace them. how bad were you leaking oil.
Once a spark plug gets water ingress it is usually damaged even if dried out. I repair head gaskets for a living and this happens alot.

I would get compreed ait on all electrical contacts and replace plugs. injectors should dry if you blast the water. It fires when you rev it as the compression is raised and the small spark is enough to ignite the mixture at idle the spark isnt powerfull enough.


...has a job!
Ya fo sho...I was hoping it would explode on the way home so I'd have an excuse to buy the Volvo wagon I've wanted for so long...