here in AZ, my 75 stock drivetrain with all emissions stuff in place on the 2f got as follows:IDLE READING--1139 HC vs 250 max allowable, and CO of 3.99 (1.50 is passing) for the LOADED READING....

ok experts, help another poor slob get through emissions with the FJ... geesh. i can't believe this, but there WAS an advantage to living in houston... no emissions!!

Originally posted by peiserg
here in AZ, my 75 stock drivetrain

A 28 yr old truck isn't exempt from emissions in AZ?

First the dumb questions Last tune up was?? PCV Valve replaced when?? Carb adjusted when??

My old 75 when it had the 2f in it passed everytime, but I use to do the following first.

Adjust the valves
Full tune including points, wires, cap, rotor & plugs.
Replace the PCV valve
replace the Air Cleaner
1/2 tank 92 octane

Last confirm timing was dead on the center of the observation window on the bell housing.

I'm sure there are people here who can tell you what is wrong by your numbers, but I found that the newer the parts the better I passed.

Good Luck

P.S. That was to pass a treadmill test in California.

OK Peiserg, I answered some of these questions in your other thread. I will explain all of this to you a little later. Right now my wife needs my help to finish my daughters bedroom. So....
I am off to save the day.;) :D

Rich
Kruzrtek
kruzrtk@xmission.com

Oh I just saw MVANDYKE's reply and would contest the 92 octane fuel. It is actually better to run a lower grade(but still high quality) to help with emissions a little. The lower octane has a quicker burn reaction than a higher octane. That is why higher octane helps with pinging, because it has a slower burn reaction.
Anyway, the lower octane fuel will start to burn sooner and thus you will get a more complete burn due to the fact that it has a longer burn time in the cylinder. Hope that makes since.
It ignites sooner, burns longer, and more thoroughly. Thus a cleaner burn!

Oh and the HC's is straight raw fuel. As if you have a complete misfire somewhere. Bad plug, ignition wire, misadjusted carb causing lean miss, PCV can contribute, oil broken down(needing changed). All these things cause high HC's. Just think about any thing that will create an unburned combustion cycle.
The CO will be related as well, but this is partially burned fuel.
Improper mixture, improper jetting, misadjusted choke, think anyhting that will not allow the proper air into the engine, and the proper amount of fuel to blend with that air.

That is all I have time for right now. I'll be back a little later.

Rich
Kruzrtek
kruzrtk@xmission.com

I always thought the higher the octane the slower the burn therefore the cleaner the burn, but a quick burn of the lower octane makes sense to me. I'm no pro and I would not bet my mortgage payment on the 92 octane. Sounds like kruzrtek is better trained then me soooooooooo. Ya what he said.

:D

It sounds like it needs a tune up.

The high HC at idle indicates that it is mis-firing. The idle mix may to too lean to ignite reliably or it could be electrical or bad compression.

The high CO under load is from running rich. It could be a bad carb or as simple as a clogged air filter.

PS. I don't believe that there is a significant difference in the burning rate of 91 vs 87 octane fuel under normal engine conditions. Obviously, the high octane is less susceptible to preignition or spontaneous combustion, but this is because it has a slightly higher activation energy. The lower octane fuel actually has a slightly higher energy content because it has slightly longer hydrocarbons meaning more carbon-carbon bonds per molecule.

This is the same reason that diesels are more efficient because diesel fuel has much longer hydrocarbons than gasoline and therefore has a higher energy content per volume

thanks for the info..

last tune up 2500 miles ago:plugs, wires, cap, rotor, fuel and air filter, timing, (no dwell on elect ign), and valve adjustment.

i guess i could do it over again...

Originally posted by Pin Head
It sounds like it needs a tune up.

The high HC at idle indicates that it is mis-firing. The idle mix may to too lean to ignite reliably or it could be electrical or bad compression.

The high CO under load is from running rich. It could be a bad carb or as simple as a clogged air filter.
per volume

pin head, do you see any benfit from changing my coil? I'd be willing to try just about anything to avoid the waiver... i've already got the specter "XR700" elect. ignition. if so, which coild would you rec??