pcleary1210

So, since 5:30 this evening when I failed smog I've been poking around in a sea of home-brew advice and technical adjustments to all things emissions related.

My 87 4runner failed smog in the following areas:

HC @ 25mph. Max is 103, I measured at 108
CO% @ 15mph. Max is .61, I measured at 1.29
NO @ both speeds. Max is 1085/1120, I measured at 1915/2189 (at 12/25mph respectively).

Essentially everything is high. As a quick background, I bought this thing for $1300, because the guy said it had a blown head gasket. A leakdown test and compression test came out great, and in the end the misfire and lack of power was a bad injector. All 4 have since been replaced. I've also replaced the 02 censor, plugs, cap, rotor, adjusted the timing and the valves, and the air filter.

After my failure I went and picked up a brand spaking new magnaflow cat, since the old one was driven for a while with a bad 02 censor and a failed injector.

So...what else should I be looking into?
Coolant temp sensor? TPS? AFM? PCV? Charcoal canister? Think a new cat will fix all of my problems, in this case?

Also, should I even consider the fuel additives to help pass smog emissions?

Any advice is welcome, I really want to pass on my re-test.

-PC

skypilot

iTrader: (1)

Water temp sensor is cheep, like $20 for mine. Check the EGR opening, if its working at all. You can lean out the AFM to help with the HC, and retard the timing a smidge.

The cat may fix it, mine all burn through.

91muddog

All fuel additives due is superheat the cat which will lead to premature failure

scope103

Your main problem is high NO, which is almost certainly an EGR problem. (A bad cat will raise NO slightly; you're much too high for a cat to help.) Go through the diagnostics in the FSM. A common problem is the the tube which carries the exhaust gasses into the plenum (upper intake) gets completely clogged. Someone on this site recommended putting your hand on the outside of that pipe: it should feel warm. If not, you'll need to pull it out and clean it (and if it's that bad you should clean the plenum too).

And no fuel additive will help NO significantly; don't waste your money.

4x4climber

honestly.... Go back and pass smog. You will pass... If you did all the stuff you said to it after you failed and you got a new cat... You should be good.

if you are willing to.... I would pull the uper intake plenum, tb and egr and clean all that stuff. Then put it together again. Only cost a couple gaskets and you be surprised what crap you will get out... Will make it run better. But aside from a timing adjustment to make sure it is good...

your cat will take care of a ton. Those magnaflow cats burn alotta stuff...

myyota

When you replaced the 02 sensor did you buy an OEM Denso 02 ?. If you bought a Bosch 02 sensor, they don`t work well in toyota engines and could be part of your problem.

If the cat is original with a lot of miles on it, it could also be a contributing problem.

pcleary1210

UPDATE: I PASSED!

I did all the repairs I mentioned BEFORE I smogged it (like, months before). The only thing I hadn't done is the cat.

This morning I pulled the cat off and....it was hollow. TOTALLY hollow, not just a hole, there was nothing inside it. So I put the new unit on, and after talking to a Toyota guy at Roseville Toyota, I also replaced the thermostat with a factory unit. BAM...the only thing that measured a little high was the CO @ 15mph, everything else was way way under average measurement. My NOx, which previously was at gross polluter levels, is now 0.

Thanks for the all the responses, guys, I'm praising allah that I didn't have to start tearing stuff apart to figure this out.

-PC

91muddog

good to hear! now i get to tackle smog on my truck!

myyota

Im so glad i don`t have to deal with that smog test crap any more sense ive moved out of california. I now live in Idaho, and there are no smog tests for any vehicles here.

91muddog

"well guy guys are ruining the earth!"

Thelast83inNJ

I guess everyone assumed when he said "picked up a new Magnaflow cat" that he put it on and still failed. Mr Scope 103 is correct, going to the next step is egr. But egr should have been checked first and we assume it was. Give the correct information and get the correct answer.