Ontario DriveClean - My log to clean up high NOX emission testing problems

[cjones101812]

what temp is your car running at?? how's the cooling system??

what speed is the test up there?? most EGR systems don't kick in til 2500 rpms.

as stated earlier NOx is formed when cylinder temps exceed 2500*F

when i ran tests in CA sometimes i needed to run it in a different gear to pass.

does your sheet also have O2 and CO2 listed?? (to see if truck is running lean or just real good cats)

 

[cjones101812]

I was wondering about this. Do you know how they are determining NOx? Is it a tailpipe test? I'm wondering if the test is sensitive to the location of the probe in the tailpipe.

FWIW, I just had my Explorer smogged last Sept and they did not test for NOx. Just HC and CO.

My understanding is that NOx production is related to combustion temp and that is why EGR is used - by recirculating exhaust back into the intake it will lower combustion temp.

The three way catalyst is also supposed to reduce NOx - three way refers to reducing HC, CO and NOx.

http://en.wikipedia.org/wiki/Catalytic_converter#Three-way_catalytic_converters

you must live in a Basic Area (2 speed idle test). or your truck is full time 4x4/AWD.

NOx is measured in ppm (Parts per Million). the test does use a probe but if there is too much dilution then the test would abort.

 

[dogfriend]

you must live in a Basic Area (2 speed idle test). or your truck is full time 4x4/AWD.

NOx is measured in ppm (Parts per Million). the test does use a probe but if there is too much dilution then the test would abort.

Full time 4wd. I live in the Sacramento area, so we are in the "Enhanced" area.

It would seem like this test would be really sensitive to placement of the probe because air is about 77% Nitrogen.

 

[G-96XLT]

My 96 XLT goes on the dyno for the etest and has a tailpipe and an ODB hookup at the same time. I've been told this car gets it the worst. my 2000 sport is 4wd and doesn't go on the dyno and passes easy.


My CO / HC are great , virtually nothingg

I'm starting to tie things together , I have one O2 sensors at 1.275V and all the others are at 0.8 , and I'm now getting a P0125 which is a cooling problem and I'm failing e-test due to high nox. maybe I'm running too hot

 

[cjones101812]

when you ran the codes...was the truck warmed up completely?? p0125 is engine not warmed up enough to enter "closed loop". look at the ECT sensor with your scanner.

which sensor is 1.275v ?? most O2 sensors can only produce 1.1v. if the sensor is showing that then your computer is leaning the mixture

0.8v is rich therefore will lean the mixture.

too lean a mix could cause high NOx.

dogfriend:

the dilution abort is sensitive. some cars ran sooo clean (volvo) that we had to 'dirty them' some so we could test them.

dilution is determined by adding CO and CO2, must be above a certain number.

 

[G-96XLT]

The 0125 has been around for a while , I cleared it and it came back. I don't know if it comes when its hot or cold. it just comes back after a few km of driving.

My last sensor is 1.275 . Last meaning that when I scan it is 4th on my list.

0.8
0.8
0.8
1.275

 

[G-96XLT]

Also just noticed the TEMP gauge is down on C , even after driving for a few minutes. The scanner shows a coolant temp of 53-63 C ,, the gauge barely moves a few mm from the C position..

 

[reserved50]

change your thermostat, its running open loop I bet also. Factory is set to go to closed loop at like 170? I totally forget

 

[G-96XLT]

I'm doing the tstat right now. I already took it off and will put a new one on after a few more drinks. I did notice a very very minor leak around the tstat housing. I hope it was just the gasket of the old one. the old tstat looked fine on a visual.

 

[G-96XLT]

I changed the TSTAT , real easy , 20 mins max and the P0125 has not come back. the only thing required was a flat head to remove the intake and a 10mm on a small ratchet with extension.

I know it is too soon to say the code P0125 is fixed but just after 20 mins of driving I can see the improvement already , the car feels smoother , there is full heat again and the TEMP gauge is right back in the middle. I was sure this P0125 was the tstat because when scanning with the ODB my heat was always between 50-60c , real low but I knew the ECT worked .. now it is up in the 80-90c where it should be for the tstat to open.

I also went through a half can of seafoam in the vacum and the rest in the tank.

bad news , the code P0402 has been lingering as pending for the last few starts , it has not come up as a full code but it is pending every time and comes back after I clear it.

 

[reserved50]

if the routing of lines to the EGR sensor are ok and EGR is good, 9 times out of 10 I have seen the Ford DPFE whatever sensors go bad. I had one car (my Toreass) that actually had a split in the housing and that allowed hot exhaust gas into it and it spat melted plastic everywhere like a volcano haha. Thats sensor is a maintenace part kind of like the TFI modules that ford cleverly attached to the distributer in older vehicles, expect to replace it, clowns. I persoanlly would have tried going thru emissions the 2nd time after changing these items, would of had a better chance

 

[dogfriend]

if the routing of lines to the EGR sensor are ok and EGR is good, 9 times out of 10 I have seen the Ford DPFE whatever sensors go bad. I had one car (my Toreass) that actually had a split in the housing and that allowed hot exhaust gas into it and it spat melted plastic everywhere like a volcano haha. Thats sensor is a maintenace part kind of like the TFI modules that ford cleverly attached to the distributer in older vehicles, expect to replace it, clowns. I persoanlly would have tried going thru emissions the 2nd time after changing these items, would of had a better chance

I have seen a bunch of threads related to the DPFE on this board. It does seem to have a fairly high failure rate.

 

[G-96XLT]

I've seen the DPFE problems but I did take one from another car and still go the P0402.

the EGR valve is brand new , the PCV looks fine.

 

[reserved50]

random links
http://www.niehoff.com/techtips/n_sen.html
http://www.explorerforum.com/forums/showthread.php?t=164517
http://www.f150online.com/forums/showthread.php?p=2937426#post2937426

if the routing of lines to the EGR sensor are ok

what i said earlier if you read the last link related to 402, may or may not be it

 

[G-96XLT]

UPDATE

I got rid of the P0402 code. It was the DPFE.. It turns out the one I took from a scrap car was bad as well. I got a used one today and the code has not come back in several drive cycles and 80km, and again it also feels smoother and stronger.. I will drive around for 1-2 more days before trying e-test #4.

 

[reserved50]

I would actually feel slightly confident now it should pass and would think Im not wasting money if I was taking it in for inspection :
.Did you have another O2 code or something before also?

 

[G-96XLT]

I had several codes but most of them are cleared. basically since I last failed the e-test I cleared a P1025 and a P0402 which did make a great improvement and the idle is smoother.. I think this will make a decent improvement in the e-test , even if I don't pass I am anxious to see the improvement in the actual nox numbers.

I also have a P0133 and P0153 (slow O2) but I just put seafoam in the lines and in the fuel tank and someone told me it screws the O2 sensors , when the seafoam is gone those codes should clear. They were not there all last week and only showed up 2 drive cycles after for both of them so I doubt the sensors are actually gone.. I do have 1 new bosch on standby anyway and can pull a spare from my 2000. its great having two explorers to swap parts.

 

[dogfriend]

UPDATE

. it was the DPFE , tuns out the one I took from another car was bad too.

Told ya the failure rate is high.

 

[G-96XLT]

what do you think about the 1033 and 53 , will they go away. I hope it was the seafoam that screwed up the sensors for a short while. I can't see them both going bad in one drive cycle.

 

[96eb96]

what do you think about the 1033 and 53 , will they go away. I hope it was the seafoam that screwed up the sensors for a short while. I can't see them both going bad in one drive cycle.

Is your MAF squeaky clean?