O2's

chdesign

Member
OK everyone when i had the turbo the CEL came on due to no cat, I thought i burnt up my O2's cause i ditched the turbo and put the stock header and cat back on and still had a cel replaced the o2's and still had a CEL now I have a header eliminated the cat and put a simulator on but stilll yes a CEL....could I have damaged my MAF sensor and this is causing my bogging down? Or is it the O2's I tested the output signal of the O2 sensors and they are right on the first signal fulctuates between . 3 and .8 the second signal fulctuates between .2 and .5 so it is getting the lower signal as it should but still no go this simulator worked with bih bena nd many many other cars and i know i have it hooked up right.....when i put it on the scanner everytime it has given me a emmisions code i konw that the MAF being damaged can cause this code to be thrown as well so do you think thats it? any suggestions?
 
I overboosted once when my wastegate hung nad i overboosted to 14 psi lol plus i think there was a recall on the MAF for my car just thought of another thing that could be throwing the code I don't have the EGR connected but I don't know if that throws a code or not.
 
Maybe it can be interesting to see what code your ECU is throwing. I have bought a device to read ECU code. It is called ElmScan. It cost $65 and you can link it to any computer.

ScanTools website

My ECU is throwing 3 code. The first one P0140, is related to my 2nd O2 sensor, which I modified with a capacitior and resistor. I will get the Casper Electronic O2 Simulator to get rid of this one.

The second one is P0106, which is related to the EGR boost sensor. This one is probably caused by the check valves I installed before my Boost Sensor. In the shop manual, they say that this code is throw because the ECU have monitor difference between the intake manifold vaccum and atmospheric pressure detected by the EGR boost sensor. Maybe I will try to installed a check valve on the intake manifold vaccum line the make both vaccum identical.

The third one is P0103. This one is throw by the ECU when input voltage is detected from the MAF sensor after ignition key is turned on. That mean a MAF malfunction. Here I'm wondering if my MAF have a problem. I must find a felow Protege owner who want to swap the MAF sensor for a test.

But even with those codes, my car is runing great. If I remove those codes with my Scantool, I can run a few days before they came back and I can't see any differences on the car performance.

But some codes can change the performance of the car. Maybe you should first see what kind of codes you have and after that we can check the effect of those codes in the shop manual.


Spoolin, did your ECU is throwing some codes on your car?
 
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I am throwing the default cat code because I have none (laugh)
I am also throwing a MAF code. This only happened after I overboosted to like 20lbs once:eek:
I think this did away with the MAF however my car is running perfectly and there is no difference in driveability.
 
Overboost to 20 psi!!! (wow) You like to live dangerously!!!

That's similar to my codes except the Boost sensor one. I still don't understand why I need those check valves to get my car runing correctly and anybody does? :confused: Also, lots of people got some knocking and I don't? :confused: but maybe that's because of my setup which is similar to your's less the Link system. Everybody else seem to run with an FMU.
 
Hey CH easy way to read the codes is use a paper clip or a piece of wire to jump the GND and TEN terminals on the diag. connector. Turn on your ing to the run position and the cel will flash the codes. You'll need a code list which miata.net has and it'll tell you whats up. To answer your other questions, yes the EGR will give you a code, if i remember right either open or shut. The MAF will also throw a code. Both should be indepent of each other so if both are malfuctioning you should get two seperate codes. One thing else to add is if you're not using the jumper method with diag. connector and you're using a generic scan tool sometimes the scanner won't read the info the ECU is giving correctly. I've run into that with only a few cars where the manfuacture's scanner had to be used with their propritery software to read the diagnostics correctly.
 
Ok, Chdesign, I'm only replying because I like you. Here is what I think you should do. By the way, I am seriously drunk and I am all screwed up from the T-givving dinner with Tryptophan in the turkey. So I will considdr myself drugged tonight. So any posts you or anyone reads fron me tonight, just considder them as funney and not informative. Damn, what do you know it, I can still spell,......or can I? GOD I"M EDRUNK.(rofl) Anyways, your car is ****** up because yo have a rotege that wasnt meant to be fast. Sell that piece of sh9it a get a fast car to begin with. I'm in collge righht now so I can't get a fast car to start out with so I'm pretty much screwed. I really enjoy my MP3, but you only have a 1.8L Protege. Sell that piece of crap and buy a car you can actually make faster, not a 1.8L Protege. I'm only telling you the truth because I';m drunk, so please, listen to me, you know that the on;ly real truth in life comes from drunk people. So please, listen to what I say, If you want auto x speed, go buy a cheap miata, if you want straight kick ass drag speed, go buy an old chevelle or a camaro.
 
God, I just read that post and there are so many mistakes in it I don't feel like correcting them. If you don't understand it, **** you, dont read it. (rofl) I'm just kidding, I love you all! Even the ones I argue with.
 
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