CEL Eliminator Improved.

[PFUNK5]

Okay, I'm not sure if I'm posting this in the right area, but I'd give you all the jist of what happened with my OBX 4-1 Header install with the CEL Eliminator as well.

Monday night:

Okay, I installed the header and CEL Eliminator at shop class monday night. Everything went well...used a 1Million OHM Resistor, and a Capacitor from Radio Shack. Installed everything correct, w/ the watch of my teacher. Used Soldering Iron to install resistor and capacitor.

Drove home---no CEL...until 57 miles later, tuesday day.

Tuesday night:

Came into my Auto Electric class...and explained to my teacher what was going on....We hooked up a OBD II Scanner to my car to see what fault came up to put the MIL or CEL on in my car.
The code read P0140, which meant Rear O2 Sensor "No Activity Detected". This is the Pre-Cat or 2nd O2 Sensor that was eliminated from the OBX Header.

This is what our P5 ECU does to read the O2 Sensor: Now forgive me, I might have some of this shit wrong, cuz I'm doing this all by memory.

Our ECU goes through a 2 cycle reading to read our Rear 02 Sensor...and during that process the voltage reading coming the sensor has to PEAK OVER .55 of a volt at least ONCE in order not to upset our ECU and send out a MIL. The voltage goes through a low and high flow...

With the 1Million OHM resistor, my O2 sensor stayed at a steady .47volts while keeping my car at a steady 1500rpm test on the lift. It peaked only once at .55volts, but nothing OVER.

This means that the resistor used of 1Million OHMS was way too restrictive on the voltage going back to my ECU. We cleared out the code out of my car, and put a resistor worth about 850,000 OHMS on the car. Test drove the car w/ the OBD II Scanner on...and it peaked at a .58 volts. PERFECT.

It's now been a good 2 days later, and 100+ miles on the car w/ the new resistor on. NO CEL. With that being said...if anyone gets a CEL still with the CEL/MIL Eliminator...try using a Resistor with a lower OHM. That might work for you...it worked for me.

I will post more information later on this...if anyone is interested. PM if you want too if you have a question. I'll do my best to help.


UPDATED 6-1-04

The correct Ohm Resistor to use with our Header's is 850,000ohms.
AKA: 850K Ohms.

And the Capacitor:

1uF Non Polarized Electrolytic Capacitor
ID # is 272-996, on the top left of the small package, should have GREEN labelling on the bottom.

I found this in a shelfing unit in the back of Radio Shack, bottom drawer, labelled:

[CustomMSP]

Good info!

[PFUNK5]

Thanks man...I'm hoping this will help anybody that has STILL gotten a CEL when using the Current CEL/MIL Elimnator Setup. Also helped having a full auto shop available at my hands and an extremely knowledgable teacher.

[Rism]

I dont know about u but the resistor i got says 1k-ohm

[PFUNK5]

Moderators, please move this to the how-to, if possible. BUMP please!

I'm pretty sure that is 1000ohms. the one I'm using is around 850,000 ohms. The recommended has been 1 million ohms, but it seems like people have been still getting a CEL after the code P0140.

[Rism]

Damn then the idiot at radioshack gave me the wrong one.
Does the uF capacitor have to be anything special. Mine just says 1.0uF metalized-film capacitor.

[PFUNK5]

Okay...this is what I'm gonna do...Radio Shack is down the street from me, and I'm gonna go and write down the resistor and UF Capacitor #'s so everybody can get the CORRECT one.


Be right back.

[PFUNK5]

Okay this is the Capacitor that I used and it's working nicely:

I got it at Radio Shack:

1uF Non Polarized Electrolytic Capacitor
ID # is 272-996, on the top left of the small package, should have GREEN labelling on the bottom.

I found this in a shelfing unit in the back of Radio Shack, bottom drawer, labelled:

Electrolytic, Axial (Inline) Leads, in Green.

As far as finding the correct OHM resistor, I'll ask my teacher...but I would use something weaker than a 1M (M=Million Ohms) Ohm Resistor. Stay tuned, I'll get that information as soon as possible. Probably on Tuesday.

[wannabe]

good to know! better than spending $30 on an MIL eliminator!

[PFUNK5]

As always...make sure you take your time with the install, solder the wires thoroughly for a clean install.

[acidbbg]

Good info. I think the mods should merge it into the How to i created.

Chas

[PFUNK5]

Thanks Chas!! Say hi to your friend from the 4-17 meet for me too, i forgot his name tho' I believe he was ur cousin? (whoops!)

[acidbbg]

No problems dude..

his name is Mike.

Chas

[PFUNK5]

yeah MOD's maybe move this to the How-TO?

[PFUNK5]

Bump for UPDATE please!

[YellowMP5]

great write up. i plan to install this header in the near future and i will defntly go with the 850k resistor to save my self a possible headache if i use the 1M and it still throws a CEL.

[acidbbg]

Bump

[20EVOLUTION01]

Hey PFUNK5.
I bought the 1m Resistor but was also looking for the 850k. I was not able to locate it and radio shack does not have them in thier book or at thier store. Where can I find it and can you help me get one. I will gladly pay for one or a pack.

Also, Radio Shack was very helpful in assisting me. They even let me go on thier internet to see what cap and resistor I needed cuz I forgot. Cool guyz. He just couldn't find that resistor. He did direct me to other places in town which I never heard of but to no success.

PLLLLEEEEEEZZZZZEEEEE Help before I get my Header. (smash)

[PFUNK5]

Yeo, I'll see what I can do...I'm leaving for a camping trip tommorrow until Sunday. I'll PM you if I get some info...maybe you could order one online somewhere...

[YellowMP5]

check your yellow pages for an electronics or maybe a hobby store. any tv/vcr repair place (do those still exist?) will probably have one too. is there only 1 radio shack in your town? check the other ones. here in south florida radio shacks are 3-4 miles apart. any mall will also have a radio shack.

[20EVOLUTION01]

Yup checked them all and no one has them. Unfortunatly there is only one radio shack. The City is about a 40 or maybe more mile radius, Not that big. Fucked up huh? Oh well I maybe will try my luck on the internet. I'll let you guys know. (2thumbs)

[Murda]

If you find where you can get these parts (online), please tell me.

My RadioShack doesn't have it and now I'm not even sure I have the right cap at home. I'll have to check. I have that metalized film one.

... must... get... rid.. of... cel....

[20EVOLUTION01]

If you find where you can get these parts (online), please tell me.

My RadioShack doesn't have it and now I'm not even sure I have the right cap at home. I'll have to check. I have that metalized film one.

... must... get... rid.. of... cel....

So far no luck. I will keep searching though. I have the 1m Resistor 1/2 watt #271-1134 and a 1uF Electrolytic Capacitor Part number 272-996. I hope those will work for me. I'll let you know just finishing up my header install. The Closest I came to find one was I think a 820,000 Ohm Resister. Don;t know if that will work though.

[Kooldino]

It's good info, but not "how to" worthy yet.

If you want to make a "how to", start a totall new thread, post the correct info, and post diagrams and pictures of things, as well as a step by step procedure on how to do it. Thanks!

[trbomp5]

did anybody ever find the right resisiter yet? Can't you use 2 of them to come up with the 850,000?

[vielster]

850k ohm resistors are somewhat rare. Usually you'll find 820kohm and then the next step is ~950kohm. If youwant exactly 850kohms you can put an 820kohm in series with (in a row) another 30kohm resistor. Also interesting to note, most of the cheap resistors around are about 5% tolerance (can be +/- 5% of rating) so a 850kohm resistor ranges from about 800kohms to 900kohms. I would think 820k should be fine.

Also intersting to note, voltage drops are linear with resistance (V=IR) no squared's or anything in there...so if a 150k change (from 1Mohm - 850kohm) makes a change from .47 -> .57 then you're talking .1V/150kohm...thus using an 820k will only give a difference of .02V if you drop the other 30k, so you'd be at about .59V, and I would guess that this small difference probably won't have any effect and you'll still operate fine.

Anyone used an 820k and had problems or success?

[iluvmacs]

When I got my resistor it came in a pack of 5. I went back to my experience with electronics to see if I could get something between .5 MOHM and 1 MOHM.

If you connect 2 of those resistors in parallel, they equal 1 resistor of .5MOHM. If you connect the other 3 in parallel, they equal 1 resistor of .333 MOHM. If you connect 2 resistors in series, they equal .5 + .333 MOHM or .833 MOHM.

I did this last night and will let everyone know of the results by the end of the week (after the computer figures out what's going on).

[vielster]

That's a lot of resistors to fit in a small space...if you have any trouble, just go with an 820kohm or 930kohm, they both have seemed to work fine. Actually, most comercially available MIL eliminators ones are ~970kOhm (that I've seen) so I'd think that somewhere in the neighborhood would probably be fine



When I got my resistor it came in a pack of 5. I went back to my experience with electronics to see if I could get something between .5 MOHM and 1 MOHM.

If you connect 2 of those resistors in parallel, they equal 1 resistor of .5MOHM. If you connect the other 3 in parallel, they equal 1 resistor of .333 MOHM. If you connect 2 resistors in series, they equal .5 + .333 MOHM or .833 MOHM.

I did this last night and will let everyone know of the results by the end of the week (after the computer figures out what's going on).

[iluvmacs]

If your'e good with the soldering iron it's not that much space ;)

I'm not going to mess with it unless the CEL comes back on. At that point I'm sure I'll buy new parts and start from scratch.

[iluvmacs]

I put some resistors on there that were equivalent to 850,000 Ohms and I just got the P0140 code. I don't know what code I had before when I had the 833,000 Ohm resistor on there. Now I'm really out of ideas.

I have the capacitor and resistor wired up just like the diagram shown in the other post. I have the O2 hanging in the engine bay. What else am I supposed to do? You guys don't have the O2 in the exhaust stream somewhere do you?

[iluvmacs]

I've been reading around and the CEL eliminator is to be used when you weld the second O2 sensor into the header. The eliminator just changes the signal enough that the ECU thinks that it's reading a hotter temperature than the first O2 sensor.

Does anybody know of a way to jimmy the electronics so that the second 02 sensor will read the same as the first, but a little bit higher temperature?

I guess I should call up exhaust shops and get one to weld a bung onto the header.

[vielster]

I mean sure, you could create a current mirrored line from the first O2 sensor, then manipulate that signal with a resistive network or some sort of heat controlled transistor (like a thermal diode driven transistor) to create a signal that reads as hotter than the first sensor. Somehow this just seems like a little too much work...

I've made several MIL eliminators that have worked perfectly (on other cars than protege's too). I don't know what the issue you're having is, unless with all your soldering and toying, you damaged your O2 sensor. I'd have that tested out before you decide to do too much. Once you figure out if its still good, you may want to try a proven eliminator rather than spending a bit of cash for a new bung....just my thoughts



I've been reading around and the CEL eliminator is to be used when you weld the second O2 sensor into the header. The eliminator just changes the signal enough that the ECU thinks that it's reading a hotter temperature than the first O2 sensor.

Does anybody know of a way to jimmy the electronics so that the second 02 sensor will read the same as the first, but a little bit higher temperature?

I guess I should call up exhaust shops and get one to weld a bung onto the header.

[Jeph]

Ok, so I have 2 470k resistors hooked up in series, and my cel came on again.
Does it matter which side of the resistors the cap is soldered into?
Does the cap need to be closer to the O2 sensor, or to the harness?

[vielster]

Yes it totally matters which side of the resistors the CAP is on. You change the filtering characteristics otherwise. Anyhow, it needs to go on the harness side of the resistors for it to function properly.

[Jeph]

Dammit, I pobably did it on the wrong side.... (runs out to car to check)

[Murda]

It's difficult to find these parts around town. I'm resorting to an online store.

I have found 1/4w resistors, will they work? Or, must I stick to 1/2w resistors. Planning to put a 390k+470k together in series to form a 860kohm 1/4w resistor. Will it work?

Also, found a capacitor that's electrolytic, non-polarized but not axial.
Link: http://www.electronix.com/catalog/product_info.php/products_id/5684?PHPSESSID=82ea41afaa193afb010c11c91f499441

Will this work?

Thanks!

PS. RadioShack sucks ass up here in Vancouver.

[Pheonix]

i just installed my header, i used two resistors in parallel to get ~880 ohms
i didn't take a pic of the diagnostic when the cat was present but if i can find a protege around here i will

the first pic is no mil and the second one is with the one i put on,
does .555 volts seem right to you, or do i have to go lower impedance.

it appears very different than having a cat but as long as it doesn't pull a cel then it's OK with me.

[BlkWidow]

bump for good info

[Pheonix]

It's difficult to find these parts around town. I'm resorting to an online store.

I have found 1/4w resistors, will they work? Or, must I stick to 1/2w resistors. Planning to put a 390k+470k together in series to form a 860kohm 1/4w resistor. Will it work?

Also, found a capacitor that's electrolytic, non-polarized but not axial.
Link: http://www.electronix.com/catalog/product_info.php/products_id/5684?PHPSESSID=82ea41afaa193afb010c11c91f499441

Will this work?

Thanks!

PS. RadioShack sucks ass up here in Vancouver.
that should be fine, lol, radioshack sucks ass everywhere, however my friend used to get me his 30% manager discount last xmas, got a $600 phone for $200.

you might want to check radioshack anyway
this is what i bought, http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=272-996
it's inline as someone said, and makes it easy to solder in place

150 miles and no CEL, phew

[zmanpro63]

Has anyone found where to get a 850k ohm resistor? Or will another one or combination work i.e. 2 470k ohm resistors?

[Jeph]

I have 2 470's that at the moment AREN'T working, but its too damn cold to be messing with anything so i deal with it for now.

[Pheonix]

i bought the huge resistor pack from radioshack while back, and just used two resistors in parallel. i found an 870 combo and 820

[protito]

So after reading this I have heard from 820k-1m. So which one will work the best???

[Nutari]

Hmm...

I went for 1000 miles then finally a CEL ...

reset the computer..

62 miles, CEL comes on again


guess I have to do something..

[Kooldino]

Hmm...

I went for 1000 miles then finally a CEL ...

reset the computer..

62 miles, CEL comes on again


guess I have to do something..
Maybe temp related?

what code did it throw?

[Nutari]

Maybe temp related?

what code did it throw?


no code puller thing...

(edit)


Oh yeah mods:
OBX Header, Ractive Short ram Intake, Ractive Axle back exhaust, Magnecor Wires, Denso Iridium Plugs..