Advice on emissions Retest.

[Madcapwoodwright]

Hello all,

Just got back from the primate panorama over at the emissions place on 44th.

I passed everything but the NOx (4.0 is limit, I came in at 5.3xxx)

Normally, I would just pour some denatured alcohol in an 1/8th of a tank and retest.

But now since reading here and in mud, I see EGR , o2 sensor, or cats may all be culprit s.

I wanted to get a feel for where the truck was without any "emissions trickery" first, then once I had some numbers to work with, dial it in from there.

Tires were full of air, 1/2 tank of 85 octane(now that I think of it, this gas tank full probably had Techron fuel system cleaner in it... Possible cause for fail?).

Since I guess I'm looking for some thoughts on how best to proceed here. Based on the readout from the inspection report, (attached) what should be next steps for me here?

Still reading up on these issues here and elsewhere, but given the relative "closeness" of a pass on NOx , I wondered if there were a tip or trick or some thing I can do to pass before tearing into EGR/o2/cats.....any thoughts?

Thanks!

John

 

[RayRay27]

Based on looking at your limits from your test report I am assuming that you have a 94 80 series? I was having the same issues as you. First double check your timing and make sure that you are at 3º BTDC or at factory settings. Second I know it may sound like snake oil but try using a bottle of CATACLEAN. Its about 27 bucks from the auto store but still better than buying a new cat. This stuff works. I was very skeptical about using it but my numbers dropped by about 1.5 to get me to pass on my NOx numbers.

May the force be with you

 

[Madcapwoodwright]

Based on looking at your limits from your test report I am assuming that you have a 94 80 series? I was having the same issues as you. First double check your timing and make sure that you are at 3º BTDC or at factory settings. Second I know it may sound like snake oil but try using a bottle of CATACLEAN. Its about 27 bucks from the auto store but still better than buying a new cat. This stuff works. I was very skeptical about using it but my numbers dropped by about 1.5 to get me to pass on my NOx numbers.

May the force be with you

Ray,
Lol on the snake oil. I wince to say this, but I'm kind of a BG44K/Marvel Mystery Oil kinda guy anyway, so bringing up Cataclean sounds reasonable able. I'll look at getting some.

 

[60wag]

Your CO2 is high and the CO is low so I think the cat is doing its job. I'd dig into the EGR to see if it is plugged up with carbon.

 

[Madcapwoodwright]

Your CO2 is high and the CO is low so I think the cat is doing its job. I'd dig into the EGR to see if it is plugged up with carbon.

OK...one vote for attention to the cat, and one for the EGR.....I was thinking EGR anyway, so whilst waiting for any others to chime in, I'm off to read up on EGR cleaning operations.....thanks!

 

[LXBRADY]

bottle of heat, full tank of Premium, run it on the highway for about 5 miles and bring it in hot to the testing center....so far so good with me ninety seven.

 

[Madcapwoodwright]

bottle of heat, full tank of Premium, run it on the highway for about 5 miles and bring it in hot to the testing center....so far so good with me ninety seven.

This brings up an interesting point.

Traditionally, with other Axis powers built cars (German and Japanese) I have owned, I have put denatured alcohol in about 1/2 tank of high octane and run it hard for 30 or so miles right into the emissions test. Sort of an "Italian tune up" so to speak.

Reading on mud, it seems to be the belief that LOWER octane fuel burns more cleanly, thus reducing emissions somewhat.

Here just the opposite.

I am inclined to revert back to my traditional fuel cocktail and RPM abuse to heat the cats.

However, I am also hopelessly in love with this truck, and feel like addressing relevent replaceable, aged, and questionable parts is indicated.

While I really kind of just want to get this through the revenue collection dog and pony show, and get my official state "tin" applied to my bumpers, and I really don't feel like throwing heaps of c-notes at this chasing "maybe- could -be's," I also want to be good to this truck.

I suppose the logical step is the fuel cocktail and Italian tune up. If I still fail then, I guess it's down the rabbit hole I go.

 

[LARGEONE]

bottle of heat, full tank of Premium, run it on the highway for about 5 miles and bring it in hot to the testing center....so far so good with me ninety seven.

I’m close to this...I go on a day where I can pretty much drive straight into the testing station. Bottle of HEAT in 1/2 tank of gas and I drive it like I stole something and I’m running from the law on the highway for miles before going in.

 

[Lastresort576]

Add Heet and run her hard up to the Dacono testing facility. generally there isn't a line and maybe by coincidence is where a lot of 80's pass. I've passed there twice now and I get a cel for egr to which I just clear the code before I head to the station. good luck!

 

[Madcapwoodwright]

Add Heet and run her hard up to the Dacono testing facility. generally there isn't a line and maybe by coincidence is where a lot of 80's pass. I've passed there twice now and I get a cel for egr to which I just clear the code before I head to the station. good luck!

Oh?
Ok, this is now at the top of my list

Can I use the same "free retest" there?
No issue with it not being in Jeffco?

 

[Madcapwoodwright]

One last question here,

I'm pretty sure it's been asked before, but I'm doing this soon and am out running around right now....

Do I use the "mustard or ketchup" Heet?

One or two bottles on half a tank of premium?

OR....

Do I stick with denatured alcohol?

 

[RayRay27]

You can retest anywhere you want. One bottle of red on near empty and half tank of premium. Run the heck out of her and get cats super hot.

 

[Madcapwoodwright]

You can retest anywhere you want. One bottle of red on near empty and half tank of premium. Run the heck out of her and get cats super hot.

Got it, thanks. Got all the previous tank out now. 1/2 full of premium, off to get me some heet. Test tomorrow most likely.

Thanks again guys/gals.

 

[Madcapwoodwright]

Ugh...still no joy on the retest.

Heet red bottle in 1/2 tank of Conoco's finest.

Tires over inflated.

Drive to Dacono testing like a Mumbai taxi driver.

All other gasses seemed to have come down.(see attached) NOx slightly UP from initial failed test.

I guess I'm needing to pull the EGR valve and figure out if it's needing to be cleaned? EGR Module replaced?

I am in uncharted waters here. I've never had to dig in to an emissions system any more than mixing up a fuel cocktail.

Thoughts? Advice? Resources for going through the EGR?

 

[Madcapwoodwright]

2nd test

 

[RayRay27]

Obliviously your not throwing a CEL right? You shouldn't have to completely remove the EGR. I would pull the EGR temp sensor and clean it. It may be covered with carbon. Once you pull the sensor, If you have a small wire brush that can fit inside of the opening you could spray some EGR cleaner in there and brush it out. Make sure all of your hoses going to the EGR are in good shape as well. Like I said try some CATACLEAN. It got my NOx numbers down.

 

[Madcapwoodwright]

Obliviously your not throwing a CEL right? You shouldn't have to completely remove the EGR. I would pull the EGR temp sensor and clean it. It may be covered with carbon. Once you pull the sensor, If you have a small wire brush that can fit inside of the opening you could spray some EGR cleaner in there and brush it out. Make sure all of your hoses going to the EGR are in good shape as well. Like I said try some CATACLEAN. It got my NOx numbers down.

I'll need to search for FSM diagrams to identify the temp sensor.

No CELs.

The ECT stays right at 195 around town, bumps up to 203-206 when pushed hard like today. I'm cautiously optimistic that these temps are "normal'(?)

I'm going to run this tank through since it has Heet in it, then Cataclean?

So frustrating.

 

[RayRay27]

The temp sensor is located on the passenger side of the EGR body. I believe it's a 14mm wrench if memory serves me right. In the photo it is the port directly below the diaphragm.

 

[Madcapwoodwright]

The temp sensor is located on the passenger side of the EGR body. I believe it's a 14mm wrench if memory serves me right. In the photo it is the port directly below the diaphragm.

You are an EGR god Ray.... Thanks man!

 

[LARGEONE]

Dang...sorry to hear there is more to it than heet. Bummer.