Won't pass emissions.

[helpme]

Last year when it wouldn't pass, a new cat conv was installed. This year it has hi NOX also. Do I need ANOTHER new cat?
Same problem both times- HIGH NOX. Thanks.

 

[exbass94]

What kind of cat was installed? A cheap aftermarket one or a Ford OEM one? I've heard a story exactly like this one a few months ago. He couldn't pass emissions. After replacing a bunch of parts he still couldn't pass. The guy finally replaced his fairly new aftermarket cat with a Ford OEM one and he passed emissions no problem.

 

[Rearanger]

Replacing the CAT was probably not the underlying problem. Why did the CAT fail? If you just replaced the CAT without fixing what caused it's failure then the new CAT may have met the same fate.

 

[helpme]

The guy charged me $650 and the vehicle has had only 6000 miles since then. He said it cost so much because it was a two stage one. Not sure where he got it from. I told him yesterday it failed again and he wants me to bring it in Monday. Not sure I want to go back to him.
I think the problem is I've been running cheap gas (87 octane). But I never had any problem with pinging.

 

[robmedina]

i run regular cheap gas and I drive about a thousand miles a week- no problems with mine.

 

[Rearanger]

I think the problem is I've been running cheap gas (87 octane).

Wrong.

 

[ForOffRoadDriving]

heres some things to think about that i picked up at a catalytic converter seminar i attended.....
is your engine clean enough to run clean? have you run any kind of fuel system cleaner through the truck? dirty/ clogged injectors can cause poor combustion and excess carbon build up which means your converter has to work harder (get hotter) to clean up the gases.
do you have a check engine light on? is your ecu coolant temp sensor reading correctly? is the MAF clean enough to get a good reading for the ecu? what kind of condition is your ignition system in?

http://www.apexhaust.com/uploads/catalogs/AP_EPA_OBDII_PRE_OBDII-APCC_issue2.pdf

 

[LAJ]

The temp guage started to read lower than it should last summer. I have never seen a CEL light except at start up even if I deliberately leave the fuel cap loose. Had a tune up about 50K miles ago. (It has about 197K now). It has always run pretty smooth. I think the guy just put a new cat on it as a band aid that he knew wasn't going to last.

 

[ForOffRoadDriving]

i would check into the temp gauge, find someone with a scan tool who can read your live engine data and focus on finding the engine coolant temp reading, it should be around 180-200 when running at full operating temp. i just put my scanner on my 94 today because ive been getting crap gas mileage lately and it turns out im only getting up to about 160 when driving but when i let it sit still the temp climbs up to 195 and stays there. i dont have guts in my converter or a rear 02 sensor so the only side effect im getting is poor fuel economy, but being that you need to be compliant for emissions reasons you need to get the cause nailed down before you throw on another cat. cats fail due to excessive heat, becoming fouled with too much unburnt fuel can cause them to ignite and burn hotter than they were designed to, which then melts down the substrate and causes exhaust blockage and inefficient converting of gasses. but what caused the excessive fuel build up to get there in the first place? weak ignition components or a bad temp sensor that tells the motor its still cold and needs more fuel to warm up. as silly as it sounds try treating your truck with seafoam to clean out some of the carbon build up in the engine and exhaust. this was one of the first things recommended at the seminar for shops to do when a car comes in with a po420 code. sometimes the substrate gets covered with residue and cant store the amount of oxygen needed to burn the gasses off and make them safe, and the rear 02 will catch this and trip the light telling you theres a problem, but since you have no light on this might not be worth checking into.

 

[helpme]

Many thanks! I might add, this ranger doesn't have an EGR. I noticed that it still has a sweet smell to it when it start up in the morning. I talked to another emissions inspector and he said to put 2 bottles of alcohol and fill up with BP or Shell Hitest and run it around 285. And that should get it down. (I-285 is 63 miles in circumference and is pretty much a very large racetrack). But I have to do it today as its supposed to snow this weekend.

 

[Rearanger]

I noticed that it still has a sweet smell to it when it start up in the morning.

Anti-freeze leak into a combustion chamber? Is this accompanied by thick white smoke out the exhaust? Rough idle?

 

[helpme]

Here are the numbers.

It smells like catalytic converter smell. No rough idle or white smoke.
On the 25/25 test: 2861 (max allowed is 1121)
On the 50/15 test: 3791 (max allowed is 1227)
I'm not sure if I can clean this up by the end of next week, much less end of the month.
I checked into another new one. Advance wants $258. Its the two stage one.
How difficult is it to install? I've done water pumps, ball joints, timing chains, alternators, and even head gaskets (on carburetered engines), but I have never done any exhaust work. I'm not crazy about laying on the cold slab. Thanks again.

 

[ForOffRoadDriving]

exhaust work is easy, its just like plumbing - you hook the pipes together and try not to get any leaks. if youre getting a direct fit converter than 5 bolts and a gasket is all thats standing in the way of getting the new one on, but if its a universal then your going to have a bigger job on your hands. for $258 id have to imagine its a direct fit so it shouldnt be too dificult of a job. pick up (3) 1-1/4" x 3/8 bolts with nuts and lock washers and get the bolt kit with springs for the rear flange, or check and see if the converter comes with the hardware.

 

[Rearanger]

It smells like catalytic converter smell.

You mean rotten egg smell? If so that's excess fuel in CAT - not good if it continues past warm up. As well it'll over heat CAT. New CAT will be waste of money and labor if you don't fix cause first. Without lift exhaust systems are PITA, especially if rusted, but doable and money saver.

 

[helpme]

Thanks. Been snowed in all week. No rotten eggs. I found a direct fit at AutoZone for $208. I can buy it in the next county and save $2.08 in tax.