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dewone
10-03-2005, 08:33 AM
The check engine light keeps coming on after I drive a couple hundred miles. I have the BBK mil elims, but that light that they are supposed to keep from actuating still doe's. Is anyone else having this or just me. Thinking of using another brand. Getting code P0136 Bank 1 Sensor 2 Malfunction.

smashedheadcat
10-03-2005, 11:38 AM
Bank 1, sensor 2 is the aft, driver's side sensor. I would check to make sure your connections are good there. If the connections are good then you may need to replace the sensor over there. Even though you are not using them. I believe what happens is sometimes the computer runs an electrical check on the heaters in the rear o2 sensors. So if they fail this test you'll get your light. I'd crawl under the car, check to make sure your connections are good, clear the code either with a scanner, or by disconnecting the battery for awhile, then try again. If the light comes back on, you have 2 options. Replace the o2 sensor, or have the rear o2s shut off in a custom tune. With a custom tune, the tuner can shut off the rear o2's (same as MILs) but it also can shut off the electrical check of the o2 heaters as well, meaning, no chance for the rear o2s to ever throw a code. I hope this helps.

dewone
10-03-2005, 11:45 AM
Thank you for your response.
I'll do more checking on the connections.
This heater check must be on a long basis, for it to drive for so many miles then pop on.
You don't think it's the mil elim's then.

tcrews
10-03-2005, 11:51 AM
You have to have functioning O2 sensors (rear) for the mil-eliminators to work properly. The computer is still checking and the mil-eliminators modulate the signal so that it should still be in an acceptable range (based of properly functioning O2 sensors).

dewone
10-03-2005, 12:54 PM
Gotch perhaps I should change the right rear sensor before I go and change the mil elim's. She runs rich though some guy in a Firebird even thought I was running rich. Based on exhaust smell though. Need to get a dyno tune just don't know any in the area. (Cincinnati)

psycho43142
10-03-2005, 07:39 PM
http://www.modulardepot.com/

Check with this place they are in the Cinci area.

Chris

dewone
10-04-2005, 07:52 AM
Thank you they are actually close to me. Once I finish my ram air I'll call them.
Bought a new O2 sensor last night on the way home from work ($72 with tax), will put it in tonight, see if that keeps the light off for me.

ProfChaos
10-04-2005, 10:10 PM
Though I'm by no means an expert on the workings of the Cobra's computer, my experience with O2 sensor problems might help here.

I cannot get my computer to sync with MIL eliminators, primarily because I have an aggressive X-pipe (a Bassani X-pipe from a Saleen Mustang) and have Flowmaster low-restriction mufflers. With the SuperChip installed, the best that I can do is for the "Check Engine" light to go out briefly, and only on rare occasions. I've tried resetting the computer boo-coo times, with the same result: no dice with Bassani X-pipe and low-restriction Flowmasters coupled with a SuperChip. (The error code is a generic ECU failure.) Initially, I thought that the issue might be faulty O2 sensors, as I did have a sensor failure (heater element) code and---per a helpful person on this board's recommendation--replaced the OEM O2 sensors with Bosch high-performance O2 sensors (better highway mileage [30 mpg] and better overall performance because of the tighter tuning curve). Even so, my woes regarding the "Check Engine" light continue and will not be resolved until I install BBK headers with OEM-compliant O2 sensor mounts and then run the car as it actually should be run: with pollution-control circuits intact and tuning to an exhaust that does not have MIL eliminators.

According to the owner of Grand Muffler in Smyrna, GA (a Mustang and Cobra specialist), this issue with MIL eliminators and aggressive X-pipes is quite common. His claims is as follows: "The only reason to ever run MIL eliminators and an off-road pipe is to race the car, as race fuel eats catalytic converter material--that's why off-road pipes were designed. Considering that Flowmaster low-restriction catalytic convertors do not noticably affect performance, the only thing that you get from adding an off-road setup is a pain in the ass." :)

I think that he is absolutely right. In short, I'll have invested over $2000 in my exhaust before it is finished and working properly, but, dad gum it, it's a Cobra and thus deserves that extra effort toward getting things right. It sounds awesome now with the Flowmaster mufflers and X-pipe and will sound even better with the Flowmaster low-restriction catalytic converters and OEM-compliant ceramic-coated BBK headers installed. I think that--just for the symbolism of it--I'll later pitch the useless MIL eliminators into Tampa Bay, when I go to my old stomping grounds to visit friends and family. The MIL eliminators will thus finally serve a purpose: as shark bait. ;)

cheers,
--Professor Chaos

dewone
10-06-2005, 07:54 AM
I do run pump gas. So what your saying is that I should remove the mil elims and reinstate the cats. Actually I have a new set of cats in the garage. In southern Ohio, at least the Cincinnati area the state conducts EPA tests so I purchased and installed the new exhaust, and was having trouble with the MIL coming on, as it ends up the vendor had sent me the wrong cats with the mufflers, hangers, o2 bungs....They were under sized, so I put in the mill elims to get by the test, it passed. Shortly after that the material inside the cat on the drivers side became dislodged, and was rattling bouncing around even turning and clogging. Once I found that. It was easier to chunk and sweep the material out of the cats. While I waited for the correct cats to come in. (They have) However this whole time since I replaced the exhaust (Had to for the long tube headers) I've experianced trouble with the light. Undersized to none with mil elims. So I should just have these new cats put in. I do all my own work on the car, except the headers and exhaust. I don't have a welder or bender so I figured have the same guy do it all. Now I got to let her out of my hands again. To do that just gives me the willies. Like you, it has to be right.
I was hoping to keep it a straight thru exhaust until I had to EPA again.
But profchaos makes since here. I did not yet any way but the new O2 sensor in. Perhaps I should wait until I have the new cats installed, and run it EPA intact.

tcrews
10-06-2005, 08:29 AM
I've been running a Bassani Offroad X-pipe for years on my '97 Cobra with MIL-eliminators and no issues (check light or otherwise) period.

It is true that the newer high-flow catalytic converters flow extremely well but you still will not get the same sound that an off-road pipe delivers. Also depending on the size of your exhaust and the power level of your engine...too much flow can be a bad thing....so it's a lot to take in to consideration.

Another reason off-road pipes were created (and the real reason) is that they flow more than catted pipes....especially the cats from years back and what have always come from the factory.

dewone
10-07-2005, 01:37 PM
Okay put the sensor in. I already have it. Hope thats all for now or until I get the pipe test. There supose to end the test here in December. We will see about that too. They quit before, then started back again in the past.

dewone
10-10-2005, 07:25 AM
Installed the sensor yesterday. (Drivers side aft sensor thank you smashead cat for the exact location) Have yet to run it, it's raining. So later this week I'll run off a couple hundred miles see how it goe's.
Thanks

smashedheadcat
10-11-2005, 02:35 PM
Installed the sensor yesterday. (Drivers side aft sensor thank you smashead cat for the exact location) Have yet to run it, it's raining. So later this week I'll run off a couple hundred miles see how it goe's.
Thanks

You are welcome for the location. Best of luck with it. Keep us posted on your results.

dewone
10-19-2005, 07:47 AM
So far so good with the O2 sensor change. Thanks tcrews for the advice on the sensor operation without cats.
Drove to Columbus, and back to Cincinnati, as well as around town the last few days no light.:thumbsup:

dewone
10-31-2005, 08:52 AM
Light coming on again.
Now the code is P0420
Low catalyst efficiency below threshold (bank 1)
The code was in twice this time?
After replacing the o2, I thought that was doing the trick.
Perhaps I should replace the other one and see what happens.

ProfChaos
11-26-2005, 07:47 PM
Though I'm by no means an expert on the workings of the Cobra's computer, my experience with O2 sensor problems might help here.

I cannot get my computer to sync with MIL eliminators, primarily because I have an aggressive X-pipe (a Bassani X-pipe from a Saleen Mustang) and have Flowmaster low-restriction mufflers. With the SuperChip installed, the best that I can do is for the "Check Engine" light to go out briefly, and only on rare occasions. I've tried resetting the computer boo-coo times, with the same result: no dice with Bassani X-pipe and low-restriction Flowmasters coupled with a SuperChip. (The error code is a generic ECU failure.) Initially, I thought that the issue might be faulty O2 sensors, as I did have a sensor failure (heater element) code and---per a helpful person on this board's recommendation--replaced the OEM O2 sensors with Bosch high-performance O2 sensors (better highway mileage [30 mpg] and better overall performance because of the tighter tuning curve). Even so, my woes regarding the "Check Engine" light continue and will not be resolved until I install BBK headers with OEM-compliant O2 sensor mounts and then run the car as it actually should be run: with pollution-control circuits intact and tuning to an exhaust that does not have MIL eliminators.

cheers,
--Professor Chaos


I recently found that the SuperChip in Lorena the Cobra was tuned to the previous exhaust system (probably a system very close to or at OEM), not to the off-road Bassani X-pipe. This explains a great deal in terms of what might be causing what with the MIL, as my original point of reference for the SuperChip tune-up is long gone, no longer exists on the car, and the existing error code likely has more to do with exhaust volume and restriction than it does with MIL eliminators. I also noticed that if I run Lorena aggressively for about five minutes or so (5K and above on the tach), the "Check Engine" light (MIL) goes off for about twenty miles or so and then returns--and this returning of the light no longer frustrates me, since I'm beginning to understand why. :)

Since I just spent a load of cash on suspension and front end work and am thus temporarily too poor to go wild on exhaust mods, in March, when I have enough cash on-hand to have the exhaust tweaked, Lorena gets low-restriction Flowmaster cats and an SCT dyno-tune (including a new SCT chip), to compliment the BBK full-length headers that will be added at that time. The exhaust might be little quieter then than it is now (with the off-road X-pipe), but to have a good time, I don't have to be driving a car loud enough to frighten the neighbors' cats....the motorcycle covers me there, anyway. :D

SuperChicken III at "The Tail of the Dragon" (http://webpages.charter.net/tsmith13/Dragon)

cheers,
--Professor Chaos