Failed Emissions test.. (1 Viewer)

[sideways86]

My bad I meant CO

 

[93yotasr5]

if all fails, you can get new O2 sensors from amazon. mine were about 57 each. NTK makes em.

NGK off brand.

 

[ToddD]

Thanks... and actually... I didn't read the instructions. Hmmm... I already 'knew' what I was doing. I let the booster line sip it out of a shallow pan for a while, about half the bottle, then I let it chug another 8 oz and killed the engine as soon as it sucked it up.
Let it sit for about 5 hours then ran it and POOFFFF the neighborhood was in a cloud. Drove maybe a total of 10 miles this evening, ran good. I'll kick it up I 70 into the hills and stretch it's legs to burn off the rest.
I'll report back with the new numbers.
Thanks for the lead on the O2 sensors, not a bad price at all, are you using those? Any concerns?

 

[93yotasr5]

ok good enough. hope it works man!!! yeah im using em. they are great!!! replaced em about 2 months ago.

 

[e9999]

will be good to see the new numbers since there is this constant argument about whether Seafoam does anything or not...

but I would suggest you drive the thing for a few days before retesting. You may well have a bunch of crud in your exhaust system now, possibly including the sensors and cats

 

[ToddD]

Alright, I went for another test today and the numbers are more wonky than before!

HC 4.94
CO 156.16
CO2 593.2345
NOx 2.84


These are the old numbers
HC 1.5418, the limit is 2.5
CO 32.7392, the limit is 25.0
CO2 710
NOx 4.4209, the limit is 4.5

I'm thinking the exhaust system is well gunked up after treating with seafoam, maybe all that crap is now stuck in / on / around O2s, and cats.
The only other time I've ever seen numbers this crazy were due to O2 failure.
I'm going to put more miles on the truck, see if I can test the O2s and measure temps on the cats.

The only history of this truck that I know is a failed head gasket and an obvious lack of maintenance. Between the failure at #6 in the head gasket and the lack of maintenance I wouldn't be surprised if it needs cats and O2s. I'm just hoping it doesn't.
All this and no check engine light.

 

[Kernal]

Would resetting the ECU by pulling the fuse or disconnecting the battery make any difference i.e.: could the Seafoam smoke storm mess up the ECU, and if so for how long before it relearns?? IDK. Change out the oil if contaminated??

 

[ToddD]

The oil has less than 120 miles on it... which has me thinking... maybe I need to run this pig on down the road and burn away more of that crap. Wish I had an answer. I'm still expecting to have to buy O2s.
I haven't thought about the ECU, that's a really good question, I'm going out to the garage now to have a smoke and take off the battery cable. Maybe it'll reset?

 

[Kernal]

Read somewhere that fuel in the oil could cause high CO readings so like you said, maybe a high speed highway run might boil off any naptha that got into the oil from the Seafoam?? IDK. Check/adjust timing??

 

[ToddD]

The timing seems good. Right at 3.

 

[Pin_Head]

I doubt that is it a problem with the catalysts because the numbers have jumped up quite a bit. I doubt that it is the O2 sensors because there is no MIL set. It is looking more like a stuck/leaky injector.

 

[ToddD]

I doubt that is it a problem with the catalysts because the numbers have jumped up quite a bit. I doubt that it is the O2 sensors because there is no MIL set. It is looking more like a stuck/leaky injector.

Yep, still no check engine light.
I disconnected the negative battery cable last night, reconnected it this afternoon before I went to run some errands. The truck started just fine as usual and then ran at a very low idle, smooth but very low, like the needle was barely hovering around 200. I drove about 7 miles, 5 of which were at highway speed and when I got to my destination the idle was back up between 600 and 800 according to the gauge. Still running smooth.
Does that mean anything to anyone? I thought it was interesting and worth mentioning.
Also, thanks for your thoughts on the injectors, I'm going to look up how to test them.
I did notice the PCV hose is rock solid and brittle on the ends. Would a failed PCV have much affect on CO production? I think Sunday is the earliest I can get back under the hood and test some things, like the O2s and cats are still on my list.

 

[94SRUNNER]

You say the PVC hose is dry and brittle....what about the PVC grommet? They may be worth changing out.

Have you used any fuel treatment? Some guys use it and have success, some don't, and well some just think it is snake oil. I use Chevron with Techron from time to time and have had some luck with it. May be worth a shot.

 

[Pin_Head]

I did notice the PCV hose is rock solid and brittle on the ends. Would a failed PCV have much affect on CO production? I think Sunday is the earliest I can get back under the hood and test some things, like the O2s and cats are still on my list.

No, the PCV is not going to make your truck run rich.

I would look in to the injectors.

 

[TrickyT]

...Also, thanks for your thoughts on the injectors, I'm going to look up how to test them...

218K is a lotta miles on the injectors if they weren't sent out to be cleaned and serviced when the HG was done. And you're not going to be able to test them in any meaningful way yourself w/o the necessary test apparatus. Besides, you've got to remove them to test them, so if you're going to go to the trouble to remove 'em you might as well just send them to a shop like WitchHunter, get them rebuilt and tested, and be done with it. WitchHunter will do before and after tests and I'll bet you'll find a big difference. They're usually pretty fast too, so your truck will only be down a few days.

 

[Kernal]

FWIW: Every 2-3 thousand miles I add one or another of the various in-the-tank injector cleaners (Lucas, Techron, whatever) usually to about half a tank of gas. No idea if they really make a difference but no problems with my injectors so far. I'm sure a professional cleaning is much better but maybe in a pinch worth a shot??

 

[ToddD]

I'd bet the injectors have been neglected like every other part on this old cruiser. I don't understand how the injectors work on 80s or how they could create such a problem with emissions but I'll read about them later when I have time. I'll look up that company WitchHunter as well. Thanks much guys!
Emissions testing always confuses me... especially in a vehicle that is new to me.

 

[ToddD]

Is this correct? I didn't know what to tag '3' as. I guess it's just EGR valve to intake.

There's some rumble and shake coming from here for less than a minute at start up when cold. I can't find it in the FSM. It even shakes the air intake housing a little. Kind of like a little bass drum.

Never mind... found the hose diagram, still need to figure out what my little bass drum part is called...

I've got good flow out of R not very good flow out of P.

Also, I'm thinking I'm missing a hose. See yellow arrow, there's a place to attach a vac line. Also, another attachment point next to the intake end of the P line.

Play time is over for today. Time to head up to Evergreen to cut firewood at the family's place.
Thanks again for any thoughts. I was hoping to get more testing done but ran out of time.

 

[Pin_Head]

The EGR system primarily controls NOx. I can't see any way it would contribute to high CO. If it was stuck open, it might have a lean misfire at idle with high HC. If it was stuck closed, you would probably see high NOx. You would likely have the MIL set.

Since you have a FSM, follow the trouble shooting guide for high CO.

 

[ToddD]

This is all I have found in the FSM regarding high CO.

1. Restricted air filter
2. Faulty SFI systems:
Faulty pressure regulator
Clogged fuel return line
Defective ECT sensor
Faulty ECM
Faulty injector
Faulty throttle position sensor
Faulty MAF meter

Air Filter is new. Checked one box, only 7 more to go.