So I gave my car to my brother to drive while im out of state and im trying to troubleshoot what might be wrong with it since it failed emissions with HC at 437 (allowable 174) and CO 1.51 (allowable 1.12). So yeah its running rich and im going to have him lean out the variable resistor to see if we can get it to pass that way. But im wondering if the FD fuel pump I installed (this is an 88 T2) would cause the car to run as rich as it does. I also use premix in the car and im not sure what effect that has on emissions (I mix one ounce per gallon).

edit: This is a stock port s4 t2 block with S5 turbo, emissions rack removed and air pump is plumbed directly to car. There are no other fuel mods other than the fuel pump..

 

one once per gallon!!!! that is quite a bit. I mix 2 oz per 3 gallon, but run a clean (unmixed) tank for emissions. Pre-mix will almost definetly cause you to fail. Especially on stock ECU.

Just fill up 1/2 tank without premix. But be sure to run the tank pretty low before filling up.

Then dump TCW3 in the tank right after you leave the station.

 

So you guys are saying that premixing will cause you to fail emission. Would you still fail with Idimiteu Rotary premix

 

never used it, but I'm sure it will increase CO. typically, oil contains much more petrolleum than gas.


EDIT::
just read a description from http://www.idemitsu-usa.com/page_211.htm

So you use this with the oil metering system, instead of synthetic or regular oil? or do you premix with it?

Oh, nevermind, found http://www.idemitsu-usa.com/page_210.htm

 

Typically you are supposed to use 1/2 oz per gallon. If your oil metering pump is busted/removed/disabled then you need 1 oz per gallon.

I wonder if premix is the reason why my emissions went up a little compared to the P.O.'s emissions test. It was half of average for 2 of the 3 pollutants on his test, about average for the 3rd pollutant. Same for the owner before him; I have the actual printout. But when I went my emissions were just a hair above average. I dunno, could have been a lot of reasons. I mean I didn't do anything to prep except warm up my car.

I use 1/4 oz per gallon. I still have my OMP.