I have a 1991 300zx N/A with 183k miles on it. Should I seafoam. Many people say it will mess things up and many say its the best thing you could possibly do to a car with high miles. I would do the 1/3 Gas tank, 1/3 Oil, and 1/3 intake if i were to do it. GOOD IDEA OR BAD IDEA

Seafoam is useless in the gas tank, harmful in the oil and covers up problems in the intake.

Seafoam contains nothing that will clean injectors. A good injector cleaner is BG44K or Redline S1.

When Seafoam is used in the oil the oil thins out and needs to be replaced prematurely and again it contains nothing to clean varnish or sludge. Use BG 109 AKA BG Quick Clean for varnish or Marvel Mystery oil for sludge.

Seafoam just temporary cleans the intake a tiny bit but it does'nt really clean anything too good, unlike manually cleaning ti with your hands, brush, rags...

If you don't believe me just search and you will see, I also summed up the info because I am laaaaazy.

I don't agree with the above post I have used seafoam and had no issues you will need to change your oil after about 100 miles though. I think it's benificial it helps break up and clean the carbon deposits. I do agree putting it in the gas tank is useless though just do the oil and then suck up most through a vacuum line.

I dont think its a good idea. If you ask me it isnt very beneficial. You engine has a lot of miles and I'm sure it has plenty of carbon buildup. however I have heard of people using this and it breaks up all the deposits but yields a loss in compression or the valves wont seal right instead of helping.

yeah that happend to my friends car, there was gaps in his cylinders that were being filled by carbon build up then the seafoam opened the holes. It cleans out the fuel lines i heard when you put it in the gas tank. I am due for an oil change anyway so I would seamfoam then change the oil same day with Castrol Syntec.

If you want to clean your crank-case, do an engine flush with and engine flush additive. As far as fuel tank and lines, the only thing i have see that actually does some good is the water remover/line conditioner. DO NOT EVER RUN SEAFOAM THROUGH A TURBO! I realize your car is NA, but I though i would just throw that in.

I personally think it's a waste of money even if it does no harm. If you want to clean your fuel system, take it in and have a Motorvac done. http://www.theautochannel.com/....htmlIt circulates a safe chemical through the system via a pumping unit and it removes all harmful deposits. We have one at our shop and it really is good.

Putting it through the intake is a waste of time as it goes through so quick, and so little amount that it can't clean anything. Take the IACV and Air Reg off and clean them works the best. There are cleaners made for the TB's that work better than Seafoam

*The foremost thing to do for the oil is change it regularly every 2000-3000 miles or so with good product and you won't ever have any buildup in the engine.

NolimitZ32 wrote: DO NOT EVER RUN SEAFOAM THROUGH A TURBO! I realize your car is NA, but I though i would just throw that in.

What would happen to a turbo engine with seafoam?

Zwicked wrote:Take the IACV and Air Reg off and clean them works the best.

What is an IACV and Air Reg. I am still learning about cars sorry.

not the engine but the turbo itself, there have been instances with some guys saying that it goes through the seals and basically causes turbos to leak. I don't know if this is true but ive heard of it more then once and would rather not take the chance.

Very true. I will warn my brother, he has an Eclipse GST fully rebuilt and he was going to seafoam is just in case. thanks

i had a small knock start this past summer in my na z ,it would last until the engine got up to temp then it would go away (lifter) i did the seafoam in the oil ran that in and around 90-100 miles then replaced the filter and oil with oem filter and synth 30w and i put another 800 miles since and until i put the car away for the winter i never heard that knock again even when it started to get cold and it would take longer to warm-up i have 174xxx miles and no issues .....i woundnt use seafoam as a preventive chemical... i would use it if i had an issue though..........again