A few important questions - for me!

[Daniel]

Whatsup guys, I dont post here much =P

1. wtf is this shit? I see it on ebay all the time. Is it worth it for 20 bucks or is it b.s.:

This auction is for a Cyclone Performance Chip/Module. All vehicles have an Electronic Control Unit (ECU) a computer chip that electronically manages and monitors your car's performance that is made according to government regulations. That means that your car could be going a lot faster and getting more Power if you replace the ECU. That could cost up to 2000 dollars. This Mod will modify your stock ECU with a Cyclone Performance Chip. This mod connects to the car's ECU by replacing the Intake Airflow Temperature (IAT) Sensor. Once the module is installed, the ECU will read that the air coming in through the intake is cold air; think of it as a "default" setting on the ECU. When the ECU reads this, it leans out the air/fuel mixture-in other words, it will take in more air, and then add more fuel to compensate for the extra air coming in, thus, producing more power and advancing timing 1 to 2 degrees. Because the engine is creating more power, this gives your Car or Truck up to 20 More Horsepower!!!

k thx onwards:

2. I have had a 240sx since may 2002. Sometime in 2003 probly june after I had changed my spark plugs/wires once in june 2002, I noticed my engine would shake a little. It was fixed by changing my spark plugs and changing my catalytic converter. Maybe 6 months later and 4k miles, shaking again, very light but annoying enough for me to feel. Change the spark plugs again, its fine. Again after about 5 months. This time i buy some bullshit 4-head spark plugs (i dont know the term, they have 4 things on top instead of 1 and they are auto-gapped supposedly). Now these things go for about 3 months only and my engine shakes way more then usual, and only when i slow down and not give it gas (when i am gassing never shakes or "shudders"), idle drops from 1000 to 700 frequently. So I think its those plugs again, I change it this time with the other ones with only one on top that need gapping, the shaking is almost gone now, and idle is back up to 1000. MY QUESTION:

Is there anything else I can do to eliminate the shuddering Completely? It shudders EVER so slightly now after i change the plugs. Do i need to change the cat again? ANy input is welcome! thx so much

oh i got an injen intake, it makes loud noises when i accelerate hard =D

[skatanic28]

1. a waste of money
2. what kinda shape are the plugs in when you take em out?
thatll give you a good idea of what could be wrong. you shouldnt need to be replacing plugs with that kinda frequency. if your cat needs to be replaced again and your plugs are fouled i would imagine you are running pretty rich.

[Daniel]

they look dark. not black still colored but looks like a bit of oil on it. what does rich mean?

[skatanic28]

they look dark. not black still colored but looks like a bit of oil on it. what does rich mean?

rich just means too much fuel for the given amount of air. are you noticing a drop in gas mileage?
if its darker its either gotta be from runnin rich or worn pistons rings i believe. may want to try a compression test if there is oil on em. maybe you are gettin some blow-by and its fouling em?
hope this helps a little....good luck

[S13Grl]

Your car should idle at about 750rpms at any given time. You should look at your distributor cap and rotor, those often fix a lot of rough idle problems. I dont' know so much about O2 sensors and their relation to idling, but that may be another option too.

The Dist. Cap & rotor should not have any white residue on them. They only cost $20 together, or that's at least what I get them for from a Nissan dealer with an employee discount. PepBoys or something should be even cheaper.

[mk20116]

go the cheap route first them the expensive, if it cost you a few bucks to check em out at an automechanic shop then do it. other wise you're wasting your money doing all this repair work for nothing..

[Daniel]

"rich just means too much fuel for the given amount of air. are you noticing a drop in gas mileage?
if its darker its either gotta be from runnin rich or worn pistons rings i believe. may want to try a compression test if there is oil on em. maybe you are gettin some blow-by and its fouling em?"

Thanks so much but you lost me there completely! The car has always gotten about 17 mpg city 21 highway. The dark stuff feels oily, worn piston rings, i dont know what to do about that or how it affects my vehicles performance. Compression test - i assume I ask my mechanic about that :smash: I dont know what blow-by is. Thanks for the help!

s13grl thx for that help too but I had that problem when i got the car. I already changed cap and rotor right after i got it (2 years ago approx) and yes it had white stuff on it! I will take a look at it again when I have a bit of time :zzz: (thats something I can do very easily)

btw: car has always idled right around 1000.

[misnomer]

Worn piston rings are not something which are easily fixed (it's one of those "if you are asking you should see a mechanic" things). Basically entails a rebuild of the engine. Worn rings will let oil into the combustion chamber where it gets on your plugs and insulates them-- weaker spark, rough idle. A compression test will see if your combustion chamber is sealling properly, lower compression means oil could be getting into the cylinder.

Isn't 1000 rpms a bit high for an s13 to idle at? Not the end of the world, but I wouldn't freak out if it's idling at 700 (or even lower).

[skatanic28]

yeah i think you might wanna get a compression test just to see what kind of shape the rings are in, if you can change plugs you should be able to check compression too. although fixing the problem will be pretty costly. that seems like pretty low mileage to me, i usually get over 25 mpg highway. on my drive home from school i can usually get just over 450 miles on a tank.

btw if you do check compression, add a bit of oil in the plug hole and then test again. if the numbers do go up, you can be pretty sure its rings.