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Failed emissions badly

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#41 ·
run it on 6 cylinders instead :jester:

you'll only have 3/4s of the polution :jester:

might be able to find cats off a junker at the wreckers?
 
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#42 ·
AmberFireDaK said:
No offense but just because I haven't heard that term before doesn't mean I'm clueless

I'm pretty confident it's failing because the cats are toast, I thought it might be the 02 but it seems it's fine..... regardless I've seen new cars fail an etest, and I've seen old junkers running on 5 cylinders pass.... it's not all about how clean your engine is.

People are probably suggesting I do all that stuff cause it's a good suggestion.... except in my case all that stuff is new
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No offense taken.I was just trying to help out.We dont have emissions here and the last time I even looked at an emmissions analyzer was back in 1995 when I was in tech school.

Are you saying that your cats are new?Are they still under warranty?I thought when people have their vehicles tested they tell you whats wrong with it or maybe you go somewhere else for that.Beats me.I also always thought that if the cats were bad then it would cut on your CEL.My drivers side went out.Didnt give me any driveability problems.The CEL said that it was Catalyst System Efficiency Below threshold.
 
#44 ·
deanler said:
I think you might have a lazy o2. I know mine bounces between about .2 up to 3.8 or so
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An oxygen sensor will typically generate up to about 0.9 volts when the fuel mixture is rich and there is little unburned oxygen in the exhaust. When the mixture is lean, the sensor output voltage will drop down to about 0.2 volts or less. When the air/fuel mixture is balanced or at the equilibrium point of about 14.7 to 1, the sensor will read around .45 volts.

The 02's dont go any higher than 0.9 volts.:twothumb:
 
#46 ·
SMD500MXZ said:
If you could find or make a video of that (rental minivan maybe?) that would be a nice thing to see.. much rather see it before I try it on any vehicle.

Take a video!:mullet:
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I had a friend that was going to pull his motor down (thought he had a bad rod). I talked him into pouring water down the intake after he got the engine hot. It pelted the garage door (& the person standing there) with the carbon that was in the engine. Knock went away. Just don't dump to much at one time as said earlier.

Toby
 
Discussion starter · #47 ·
Bos-R/T said:
No offense taken.I was just trying to help out.We dont have emissions here and the last time I even looked at an emmissions analyzer was back in 1995 when I was in tech school.

Are you saying that your cats are new?Are they still under warranty?I thought when people have their vehicles tested they tell you whats wrong with it or maybe you go somewhere else for that.Beats me.I also always thought that if the cats were bad then it would cut on your CEL.My drivers side went out.Didnt give me any driveability problems.The CEL said that it was Catalyst System Efficiency Below threshold.
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My cats are only about 2 1/2 years old, the truck only gets driven 6 months out of the year and it's usually with my cutouts open. So there's no reason the cats should be messed up but aftermarket cats are notorious for being garbage.

Magnaflow does offer a 2 year warranty and the guy I talked to said I could probably get in on it, but..... I have to remove the cats, ship them back to magnaflow and wait for them to test them, and I doubt very much I will get honest results.

It's actually illegal for an etest tech to tell you what he thinks is wrong with your vehicle... you can pay the shop to diagnose the problem, but they aren't supposed to say anything otherwise or it's a pretty big fine

My downstream 02 is so far downstream now I'm not sure it would pick up on it properly if my cat(s) were bad.
 
Discussion starter · #48 ·
Bos-R/T said:
An oxygen sensor will typically generate up to about 0.9 volts when the fuel mixture is rich and there is little unburned oxygen in the exhaust. When the mixture is lean, the sensor output voltage will drop down to about 0.2 volts or less. When the air/fuel mixture is balanced or at the equilibrium point of about 14.7 to 1, the sensor will read around .45 volts.

The 02's dont go any higher than 0.9 volts.:twothumb:
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Now that's good info
 
#49 ·
How long have you been driving it before you took it to get tested?Maybe you should run the piss out of it,blow whatever carbon or raw fuel thats in the cats out and retest it again.And since you dont hardly drive it then maybe you should send the cats off for warranty.It wouldnt hurt.I love warranty stuff.Magnaflow is a pretty good and big company and I dont think it would hurt them if they warrantied some cats for you.How is your truck set up from factory,2 precats and one cat,three 02 or four 02 sensors?
 
Discussion starter · #50 ·
Yeah I think I'm gonna find some methanol, or that isopropyl and put as much as I can in the tank, then drive the piss out if it and hope it works.

The truck had 1 cat after the Y pipe with 2 02's... one in the Y and one after the cat.
 
#51 ·
AmberFireDaK said:
Yeah I think I'm gonna find some methanol, or that isopropyl and put as much as I can in the tank, then drive the piss out if it and hope it works.

The truck had 1 cat after the Y pipe with 2 02's... one in the Y and one after the cat.
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drive the piss out of it but make sure it has the super high concentration of the alcohol in the tank when you go to test.

If its still bad its your cats and Ill bet they melted down
 
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#53 ·
Looking at the O2 sensors on a scanner is not an ideal way to diagnose if they are working properly or not. Problem is that the scanner can't read fast enough to be able to see what the actual switch rate of the O2 sensor is and alot of scanners will actually slow down the refresh rate depending how many pids (lines of information) you have displayed or are reading. An O2 sensor has to have a lean to rich and rich to lean transition time of no longer than 100 milliseconds for the pcm to properly control the fuel mixture. If the pcm can't properly control the fuel mixture then the cats will not work properly. Like said before O2 sensors swing from about .2-.9 volts and Dodge O2 sensors actually start off at 5 volts when the they are cold and then the voltage drops when they come up to temp.

Are your duals custom from the manifold back or was the y pipe cut adn then the duals added. If it is custom from the manifolds back then you could potentially have a problem with the O2 sensor placement, either too far back or too far forward in the exhaust stream.

Have you only had one test done on the truck? If so then I would have it tested again but before you have them do the test run it at about 2500 rpms for 2 minutes in neutral or park so the cats get good and hot adn then have it tested. I don't know how they test in Canada but when I used to do emisison testing in CA if a car failed we would automatically have to do a preconditioning, like what I just explained above, and then rerun the test...alot of times the vehicles passed with flying colors. If the cats are a little weak then they take a little longer to light off and the preconditioning helps them do this.
 
#54 ·
AmberFireDaK said:
The truck had 1 cat after the Y pipe with 2 02's... one in the Y and one after the cat.
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This just sunk in....


So originally it was set up like this and now you have true duals??? If this is the case what is monitoring the fuel mixture coming out of the bank that doesn't have an upstream O2 sensor in it??? If there is no upstream sensor in both banks on a true dual exhaust system then the pcm CAN'T control the fuel mixture.

Or am I not reading something right here...been known to happen
 
#55 ·
l1tech said:
Dodge O2 sensors actually start off at 5 volts when the they are cold and then the voltage drops when they come up to temp.
.
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Wow.I didnt know that.Im not saying your wrong but when one of my cats went out and I was messing around with it with my genesis scanner ive never seen it ever hit a volt and not on any of the other cars ive ever seen on my scanner,when cold,ever get past a volt.Is that 5 volts for heating the heater up?I would think 5 volts would be pouring raw fuel out the tail pipe.Thats good to know though.Im gonna check that out here in a little while.:twothumb:
 
#56 ·
l1tech said:
This just sunk in....


So originally it was set up like this and now you have true duals??? If this is the case what is monitoring the fuel mixture coming out of the bank that doesn't have an upstream O2 sensor in it??? If there is no upstream sensor in both banks on a true dual exhaust system then the pcm CAN'T control the fuel mixture.

Or am I not reading something right here...been known to happen
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The only thing I can think of is if he has one cat where the Y joins together into single it have an upstream and then a downstream after the cat.So monitoring both banks at once.Didnt make any sense to me either but after seeing how many different ways the factory installed cats on these trucks I didnt pay it no mind.They did alot of crazy things to these trucks.I was argueing with someone on dakotart.com about my setup which when I bought it it had 2 cats and 2 cats only with 4 02's.They were all telling me that my truck originally came with 3 cats.Two pre cats and one main cat.And so I didnt understand why my truck didnt have a 02 on the main cat if thats how my truck supposively came from the factory.
 
#57 ·
Bos-R/T said:
Wow.I didnt know that.Im not saying your wrong but when one of my cats went out and I was messing around with it with my genesis scanner ive never seen it ever hit a volt and not on any of the other cars ive ever seen on my scanner,when cold,ever get past a volt.Is that 5 volts for heating the heater up?I would think 5 volts would be pouring raw fuel out the tail pipe.Thats good to know though.Im gonna check that out here in a little while.:twothumb:
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The initial voltage will be 5 volts, if you are trying to monitor it with a scanner you have to be set up right away because it will pull down to normal voltage very quickly...I'm not sure if the Genisys is capable of that I haven't used one of those in years..I've given up on aftermarket scan tools and have switched to all OE tools. Once the sensor is heated it should never go above 1 volt. This is only on the Dakota, Rams, Durango and GC I don't recall if I have ever seen it on any of the cars and it doesn't apply to other mfg's.
 
Discussion starter · #58 ·
Bos-R/T said:
Wow.My truck has 2 cats and four 02's
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2000 > 2001 :nana:



My stock exhaust had the upstream 02 in the Y pipe then the cat then the downstream 02

My duals are setup almost exactly the same way, headers with the down tubes nearly the same as stock, the X pipe is in the same location as the stock Y pipe with the upstream sensor in the X pipe. It reads both banks same as stock.

Only the 1 test this time, but it passed 2 years ago maybe 6 months after I put the exhaust on.
 
Discussion starter · #59 ·
I bought 4 bottles of HEET to throw in (355ml ea.... all they had) After I picked them up I found 99% isopropanol at the drug store.... grabbed 2 bottles of that (500ml ea.)

The gas tank is about 80% full... can I mix the 2? and will what I have be anywhere near enough or am I going back for more?
 
#60 ·
l1tech said:
The initial voltage will be 5 volts, if you are trying to monitor it with a scanner you have to be set up right away because it will pull down to normal voltage very quickly...I'm not sure if the Genisys is capable of that I haven't used one of those in years..I've given up on aftermarket scan tools and have switched to all OE tools. Once the sensor is heated it should never go above 1 volt. This is only on the Dakota, Rams, Durango and GC I don't recall if I have ever seen it on any of the cars and it doesn't apply to other mfg's.
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I love the genesis.That damn thing does everything I want it to do.I cant afford to get scanners from every make of car.I work on imports so thats probably why I never seen that 5 volt before but when I get back to shop Monday im gonna check out that 5 volt signal on my dak.Learn something new everyday.:D
 
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