Yes check the ecu it usually wouldn't run right if those sensors are actually broken, cause it puts a lot of extra fuel if its not at running temp... (coolant temp sensor.) then check wiring.

When you show those codes it usually means you have a blown ground circuit in the ecu, OR, the plug to the MAF isn't making a good connection.

Sounds like your on the right track to bring the car back to life. Possible that it's more wiring issues a too since that's what you've been fixing to this point. Good luck.

Multple mas codes can simply mean the car was ran without the maf plugged in. Clear the codes and see what comes back

I agree clear the codes see what happens.

Thanks for the replies everyone, finally got some time to put more time to it. @pauleyman and @yamaripper415 , I've reset the codes like 2-3 times over the course of fixing wiring and other things. The codes just keep coming back. So I've tested the wiring and everything seems to be be getting to the ecu ok. I did continuity testing and measured voltages. I think the wiring is legit! So i moved onto the ECU and here is what I found:



Do you think this might be the culprit? I read about leaky ECU's before. Anyhow, thanks in advance!

Ya think?

@pauleyman , sorry, still a DSM newb but I'm putting my work in!

UPDATE!

ok, so I'm still battling this thing, . Here's where I am at now.

So I had the ECU cleaned and leaking caps replaced with the proper specs. I took it to a local electronic repair shop that came highly rated and well liked on yelp. The repair person said he saw no damage to the board from the leaky stuff. He cleaned it up and soldered in the new caps. I returned and plugged it in and still got all the codes 13 (AIT), 14 (TPS). 21 (coolant temp) and 25 (Barometric Sensor). So i figured to start with the MAF since it had 2 of the 4 sensors bad. I figured the MAF must be bad (even though the thing shines like new and the previous owner said he just replaced it before sitting) So I set search for a maf and came across a 2g maf / chipped 94 ECU / and !G to 2G adapter harness. I figured, might as well upgrade if I'm going to buy a MAF right?

Well i came home and swapped the parts. Plugged in the 2G MAF, adapter harness, and chipped ECU. Turned it on and it barely idled. I called the guy i bought it from and he swears the chip was burned with everything stock except 2g maf and 540 injectors but would work fine with my setup. Well It didnt. ..and it was now throwing 12 (MAF) and 25 (Barometric) The rest of the codes disappeared. I figured it may be contributed to clearing the ECU codes correctly.

So Chancing to have a bad MAF, I purchased another 2G MAF for a deal I found locally but got exact same results. hmm, not thinking it's the 2G MAF anymore. So on the advice of a friend, I decided to revert back to the 1G maf and stock non chipped ecu.

I plugged in the original non chipped ECU with the original 1G brand new looking MAF, only to get Codes 12 (MAF) and 25 (Barometric) as well. A buddy found his old working 1G MAF and was cool enough to let me barrow it to try. So i swapped them and got the same results. Code 12 (MAF) and code 25 (barometric) so i figured if i get the same i might as well run the newer looking maf that i owned since I truly believe it's a brand new unit.

So i plug in my new looking original 1G MAF and what the heck .. . .I'm down to 1 code. . .the 25 (barometric sensor) I did nothing other than swap parts and clear codes at this point. Sort of wondering how the codes little by little began to disappear. I guess it might just simply have something to do with getting bugs out of the system and electronics on a car that hasn't moved in 3+ years? not sure.

So at this point i go to my repair manual. there is a small section on how to check correct operation of the barometric sensor. One is voltage reading to pin 6 and ground continuity to pin ? (i forgot) Anywho, voltage was a little high (out of spec) and ground seems to be there.

Me and with a friends help, checked continuity from the pin side to the wire side, then wire side to the ecu. all of it checked out. No broken continuity. I have good ground to the ecu (both black wires). I have ground to pin 17 (ground going out to the sensors). And ground again at the MAF plug (all checked with test light) So continuity and ground checked out for the Barometric sensor.

Here's another side note, when letting the car idle, the CEL sometimes turns off for a few seconds and pops back on again. then pops off and back on at random intervals. the buzzer though never stops throwing code 25 regardless of what the light on the dash is doing.

So I'm doing research online to see if i can find something and noticed a trend. .now this makes it VERY curious. The exact combination of codes i'm getting seem to pop up over and over again . ..check out these links:

http://www.fullthrottletech.com/archive/index.php?t-5302.html
http://www.dsmtalk.com/forums/showthread.php?t=213705
http://www.dsmtalk.com/forums/archive/index.php/t-133364.html

None of them have final outcomes so I unfortunately don't know what they did to fix it or what they found but I really find it curious that a trend is starting to occur with the SAME codes. Could it be as one guy suggested a bad ground? or someone else pointed out these are all on the large ECU connector, could there be something there as well? I would love to hear the opinions from DSM experts or anyone willing to help! I've requested the help of local DSM'ers (even offered to tip!) to possibly switch ecu to help narrow down the possibility of it being bad but haven't gotten anyone to volunteer here in SoCal. What would you guys do next?

Thank you in advance for your time!

I would have spelled out that the drivers running those sensors lost an internal ground, or blew open. It doesn't take but less than 2 amps to knock out a driver - which are those long black devices soldered to the ECU's momboard.

Easy way to blow a sensor's driver is play with the sensor's connection with the power running through the sensor - like with the key on, motor idling, and similar.

DSM1G90 said:

I would have spelled out that the drivers running those sensors lost an internal ground, or blew open. It doesn't take but less than 2 amps to knock out a driver - which are those long black devices soldered to the ECU's momboard.

Easy way to blow a sensor's driver is play with the sensor's connection with the power running through the sensor - like with the key on, motor idling, and similar.

Click to expand...

When he plugged the main grounds into the ecu and then the plug with the sensor ground, the ground at the maf started to work again ( had a test light on it to see when the ground would come back on). Is it dependent on the driver for the sensor ground pin to work?

Called "closed loop" situation.

Things have to be in a closed loop (complete circuit) for operation to be complete.

When a sensor, or driver opens up, things go into an "open loop" condition and you get the CEL as a warning light that parts of the ECU went into an "open loop" condition-be it a sensor, driver, or both..

When all systems in the ECU are closed, is when the CEL stays on for a minute for final check, then goes off.

So your vote is bad ecu right @DSM1G90 even though I've tried two different ecu?

Idk where your from but there's a place In Taunton, Ma in the industrial park that does ecu rebuilds. They charged my brother 250 I think if you can't find one cheaper.

I work with electronics every day. Boards can look like crap and still function perfectly, the opposite can be true as well. Look nice and clean and have blown components. You need another ecu. Check out the classifieds and see if ya can find one for cheap. Troubleshooting the ecu will be difficult as im pretty sure no schematics are openly available.

And, with momboards in general, they're not just a one layer board.
They can have many layers which each layer having a separate circuit that couldn't be placed underneath with the rest of the circuitry.
Thus, one of those inner layers can easily open up and this usually calls for a replacement momboard.

-DSM

I'm going too continue my search for someone to to help or a third ecu. Just a quick FYI, I have now back codes 13,14,21,25 . This is insane

Brownrice80 said:

I'm going too continue my search for someone to to help or a third ecu. Just a quick FYI, I have now back codes 13,14,21,25 . This is insane

Click to expand...

Send it to the guys at ECMtuning.com They know our ECU's like the back of their hands. They mostly reply by email. They would fix and also set up your ecu also so that you would be able to upgrade, tune, and program the ECU yourself.

@ceedawg , That might honestly be the best way to go I guess. At least I will get a definitive answer on both ECU since I cannot find anyone around here willing to help. Thanks for the suggestion.

Brownrice80 said:

@ceedawg , That might honestly be the best way to go I guess. At least I will get a definitive answer on both ECU since I cannot find anyone around here willing to help. Thanks for the suggestion.

Click to expand...

No problem I'm almost positive that those guys can help.

So I thought I'd come back with a progress report. So turns out that both ecu's I had were bad. The repairs done locally were not done 100% and the ECU i purchased from a local guy named Cody had more problems than a cub scout at never land ranch. He wouldn't give me a refund, exchange or trade so I just paid the $90 to fix that ECU and another good amount for the stock ecu. Well after I got them back, I put in the original ECU and TA-DA! Problem solved! It's partly my fault since I really didn't think the chances of having TWO bad ecu's were slim especially after Cody claimed he literally just unplugged the ECU from his perfectly running car. Turns out there's a section on the ECU when it goes bad will give off the group of CEL that I and others were experiencing in the threads i Found. I hope this thread helps others to find the solution to their problem and save weeks of testing wires, parts swaps, and general frustration! Thank you all for your help and suggestions! Will post pics this weekend once

Now onto figuring out if this caked on stuff in the wheel well is something that I need to be concerned with. Great start to my DSM life eh? haha

Sounds like the sensor ground trace is bad on the board. Try following the trace off of pin 24 on the board.

@donniekak , i think we figured it out man! Thanks for the tip though!

Don't worry about the rough start. I got a '98 eclipse in 2000, but had to let it go, got an '01 and had to let it go, back to a '98 and looking at a rebuild. It's a challenge, but worth it. These cars drive like a dream when they're right.