Miasma

I was a little concerned that my vacuum was too low, so I tested compression today. Keep in mind that I am over a mile high in altitude and also that I just did some major engine cleaning last weekend so any carbon deposits that may have kept pressure up are now mostly gone, so this is the lowest I should expect my engine to be at any time.

Looking at the cabin from the front of the car, all units are psi:
Front Left: 145
Front Middle: 150
Front Right: 145
Rear Left: 145
Rear Middle: 145
Rear Right: 145

Considering atmospheric pressure (12.2psi or so), this indicates a 10.5:1 compression ratio.

At sea level, with 14.7psi atmospheric pressure, 145psi compression would be 174psi.

At sea level, the nissan minimum compression is 142 min and 185 standard out of factory.

The engine also had somewhere around 20 minutes to cool down so it was not ideally hot for maximum compression.

I also got a 02-01, ignition signal circuit, code after replacing everything (including new ngk platinums ), that was not unexpected, I reset the code and everything looks good now.

So, I guess this confirms my vacuum being low because of altitude since it does not appear that i have any sort of piston ring leakage.

Hope this helps someone!

Miasma

nothin to say?

KINGMAX

actually, yes, I just had a TBI done to my car at work today. I wonder what my comp. will be at now, I only have 61k so I imagine it will not be much different. I am going to the track tommorrow and I am hoping I can do as well as I did last time. I bought new plugs but I didn't have time to put them in, I know a TBI can potentially fowl the plugs w/ all the carbon deposits being flused out. I drove about 60 miles VERY HARD to make sure I flushed everything out. My car hardly smoked at all after it was done so I am thinking my carbon depoits were very minimal. But that IS very interesting, thanks for the info.

Miasma

TBI? Throttle Body Intake...?

matty

iTrader: (54)

Whats a TBI ???? sounds interesting

-matt

KINGMAX

It is a throttle body and fuel injector cleaning

Miasma

gotcha, figured it was something like that, but just wanted to verify.

matty

iTrader: (54)

Fuel injector cleaner can be found at an auto parts place ?? How many step process is it ?? Does it work good ??

-matt

Miasma

www.carfood.net get the B&G 3 step process. It is fantastic, my car is running great.

matty

iTrader: (54)

So step 2 is in the gas tank, and 1 and 3 what do you do ?? Is it the $70.00 one on that site.??

This will clean all the injectors good right ??

-matt

KINGMAX

Bg products is the same that I used. The additive that is used in the gas tank is pretty much the same as what you can buy at the store chemically, but in a much more concentrated form.

JMAXIMA

the BG TBI works two ways... the way it was done to my car and Will's (kingmax) was via a compressed canister with a line fed into out tb... your car is run @ idle for 20-30 min... and in theory it is supposed to remove the majority of carbon deposites within the tb, heads, and intake manifold. then you run the crap out of the car to blow out all the junk... then a very strong fuel additive is used for the fuel system. would i pay what our dealership charges ($120), hell no... but since i paid $30 for it... it is a worth while thing to do. oh, the other way of doing it is by using a fitting that attaches to a vacuum line... essentially the same thing.

matty

iTrader: (54)

Did you buy the $70 kit on the site ??

-matt

Miasma

yup