|11-16-2013 10:27 PM|
OK, Looking over everything again, Lambda readings, CO2, and other stuff, I want to see if there is a way we can run this a tad rich...
Since the Cat is working great, Im SURE it can handle it, and the + lambda, combined with CO2 over 14.7% both say you are running a tad lean anyways.
So, HOW do we trick the computer into thinking we are lean, to get the computer to run fatter.
Without doing anything illegal.
1) is your O2 sensor biased a tad rich, sending a slight rich signal to the computer making the computer pull a small amount of fuel, so if this is the case, we compensate with a NEW (NOT BOSCH) O2 sensor.
2) Coolant temp sensor, does it match the actual coolant temperature?
A HIGh coolant temp causes the computer to lean out the mixture, a LOWER coolant temp causes the computer to ADD fuel, we compensate by replacing the CTS. OR replacing the wire with excessive resistance.
3) Fuel Pressure, if its low, and the computer cant compensate, you will run lean, replacing the fuel pump OR a defective fuel pressure regulator can rectify this.
Also make sure the FPR vacuum is hooked to MANIFOLD VACUUM, if its hooked to ported, it will pull pressure when its supposed to add it...
4) Plugged fuel filter
There is more, but im too tired to think about it right now.
|11-16-2013 07:45 PM|
|11-16-2013 07:23 PM|
|11-16-2013 04:15 PM|
|redneckbrat||Going in again today. I'll let y'all know what happens. I was looking at my valve cover, found some loose bolts, tighten them, maybe I wont leak anymore oil.|
|11-13-2013 09:10 PM|
|11-13-2013 02:19 PM|
|redneckbrat||I think we figured out the internal heat issue, was way low on coolant. Seems i have a leak. Changed the heater hoses, will change the upper rad hose friday|
|11-02-2013 02:55 AM|
|redneckbrat||I'll check in the am what plugs I'm running|
|11-01-2013 11:44 PM|
|11-01-2013 11:10 PM|
I have not check the freeze plugs, I don't remember seeing them check those either.
I didn't qualify for the CAP program from BAR. I am pretty sure we got all the cracks. It was removed to do all the welding. I've been taking it to smog 'n go, they are closest, not sure they will do a cold test. This last time they ran a couple big fans to help cool it down. I've not changed the tstat, I can only guess that it is correct. I spoke with the tech for about 15 mins after the test, he spoke mostly of excessive internal heat. I have no idea where the freeze plugs are.
|11-01-2013 10:24 PM|
Lets see, Using the Lambda calculator:
Free Automotive Calculators
1.003 15MPH test 1
1.004 25mph test 1
0.9999 15 MPH test 2
1.003 25 MPH test 2
0.990 to 0.980 is within an acceptable range of 0.98 to 1.02
1.0 perfect for emission and CAT operation (1.005 to 0.995 good for CAT operation)
We know we are in fuel control, the computer is working and doing its job well, but we still have a high NOx issue, so if I was working on your Jeep, the next thing I would do is run a ASM (Dyno) emissions test, in 5 gas ASM mode, and sniff BEFORE the cat.
Why before the cat? the NOx reduction portion of the cat is in front of the TWC, if there is excessive O2 before it will severely reduce the NOx reduction, this gets hidden by the OC reduction portion of the cat using the extra O2 to burn up excess HC and CO, testing before the cat makes this visible.
Basically, our lambda readings are great, but they include what the CAT is burning.
Are you SURE you got all the exhaust leaks?
If so, there could also be a hot spot in the cooling system, If a tech couldnt get a freeze plug out, and pushed it in and put a new one over it, it can cause high NOx from that area, coolant cant flow past the old freeze plug easily, and that spot gets hotter.
Excessive HEAT causes NOx.
You have already run Seafoam, welded cracks in the exhaust.
Are you running stock temp rating/style spark plugs? Hotter ratings can cause NOx issues....
Check your freeze plugs, if any are new, there is a suspect area.
Do you have a stock temp tstat? I know they run those HOT, and that is normal. A cooler Tstat might help a smigon, but i have never seen big results from this.
Maybe take it in COLD, see if you can get him run a cold test.
I seen this work on a V6 Catera, its not legit, but it did make a difference (what fixed the Catera was a AIR pump divert valve, was diverting to exhaust all the time).
|11-01-2013 09:17 PM|
|10-27-2013 12:47 AM|
|redneckbrat||LOL, no prob, I can't think about it right now anyway.|
|10-27-2013 12:16 AM|
but not now, its late, and im kinda drunk....
|10-27-2013 12:05 AM|
|redneckbrat||the part number on my paperwork is 39005|
|10-26-2013 08:00 PM|
Yes, is says except for cats, but this works for non obd2 cats.
Just need that part number...
|10-26-2013 07:06 PM|
|redneckbrat||the description on my receipt for the muffler and cat states this: Car sound California certified Pre OBDII Catalytic Converter (EO# D-193-85).|
|10-26-2013 07:01 PM|
|redneckbrat||ok, thanks. hope I can see it. I had the muffler shop put the cat and muffler as high as they could.|
|10-26-2013 04:31 PM|
You can also explain all this to that smog tech, ask him to verify it.
Also, look for the AIR tube inlet into the center of the cat, it might be capped
|10-26-2013 04:28 PM|
GET THE PART NUMBER TOO
Its right below the D number
And post that number
Database: Aftermarket Parts Database of Executive Orders
|10-26-2013 04:20 PM|
|10-26-2013 04:15 PM|
Has your CAT ever been replaced?
If it has perhaps they put a '90 instead of a '91 cat accidently (or due to stupidity).
Not common, but I have seen it.
The '90 carbed 4.2 uses an OC+TWC and relies on an EGR to reduce NOx, it has a smaller NOx reduction front half because it relies on that EGR to reduce the majority of the NOx.
|10-26-2013 02:33 PM|
|redneckbrat||Here it is. It was about 1qt low. I can see that it would make a difference, but not enough to pass.|
|10-26-2013 12:45 AM|
But, How low?
Post your new test results please.
|10-26-2013 12:24 AM|
|redneckbrat||ok, been a while since I updated. the welding went really well. got all the cracks filled. smogged it last saturday and still failed, but it dame down. I'm going to do sea foam again with what little I have left. Curious, if it's low on oil, will that make it run hotter?|
|10-20-2013 03:36 PM|
|redneckbrat||I have a steel exhaust manifold, welded up nicely. helped, but didn't fix the issue. Failed again. NOx is at 1237, about twice what it should be. I've applied for the CAP program here in Cali and we'll see what happens. going to DMV to finish paying registration, get a temp sticker and then Tuesday I'll pay my fixit ticket.|
|10-15-2013 09:07 AM|
|CMike357||I am not a welder, but when my cast iron exhaust manifold cracked, I replaced it with a header off ebay for under $150. Cast iron is hard to weld on and make it last. The header I purchased was SS and mild steel. It held up 2 years before it cracked. Took it off and had it easily welded back up. Friend did it for free. Cracked exhaust are common on our Jeeps, a friend of mine replaced his with the flex tubing in it and has not had any problems. I didn't get that one because I wanted more of a header than a replacement exhaust manifold. Good luck and let us know how things go.|
|10-15-2013 12:32 AM|
|10-15-2013 12:32 AM|
|10-14-2013 05:37 PM|
|10-14-2013 02:00 PM|
I have seen muffler shops get a good bead in some hard to imagine areas on Jeeps in this exact same issue.
Without having to remove anything....
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