Please Help

[eclipse93b]

I dont know if the is in the right forum so if not could a mod please move it.

So like a retard I decided to move one of my guages to a different location in the car (a/f blinky gauge <-- I know, I know) and I got everything back together and ready to put away, so before I did I wanted to make sure everything worked right. I hook up the battery and I started the car and checked the safc/gauges and everything worked like butter. Well I forgot to tape up the O2 and power wire going from the gauge and they contacted shorting out the gauge. I shit my pants then proceeded to disconnect the gauge, tape everything up and put everything away. I went to start the car again and now it starts and all the power items in the car come on, however the car runs like shit pulls tons of codes and dies. Also the safc reads 100% throttle when off, and when on. The codes are as follows:

p0115 engine coolant temperature circuit
p0110 Intake air temperature circuit
p0100 Mass or Volume air flow circuit
p0105 Manifold absolute pressure/barometric pruessure circuit

These pop up 10 seconds after I start the car and hold the gas to keep her going. The car also is running way rich, it smells like when you start up a boat after priming the hell out of it.

Please help. This is my only vehicle and thanks to my stupidity I am out of one at the moment. I called my work {work at nissan} and one of my techs said that is sounds like a ecm fuse that blew. He said the car wouldnt run at all if the ecm fried completely.

Any help?

 

[JayRolla]

So before the short you did not have any of these codes. Ive heard if you have a bad ECU it can through all kinds of codes. I hope you didnt kill you ecu with the short.

 

[GVR4592]

Disconnecting the maf sensor connector will throw all of those codes except the coolant temp.

 

[Rex2342]

Take the A/F guage out completely and recheck your fuses. Once you hook up that guage wrong it's pretty much done and could still be shorting out internally. If the ECM fuse blew I don't think the car would start at all. Disconnect the battery while you check everything so the ECU resets and see what happens.

 

[eclipse93b]

checked all fuses, and relays. All fuses work perfect. I took out the A/F gauge and reset the ecu though it still runs in safe mode. The car is seeing 3hz on my safc2 [like it does when the car is off] but when its running. So this leads me to think its the MAS. Also the TPS is reading 100% which is why it kills, [running pig rich]. I checked resistance like the chiltons told me to and it reads connections 1 and 4 @ ~.76 ohms and when I check 2 and 4 and open the throttle it doesnt read at all. So I dont know if the ECM fried and is just not reading the TPS right or if the MAS and TPS were taken out when the wires contacted. I am trying to find another dsmer to swing by and swap some parts to see what is actually the problem (mas, ecu, tps in that order), however I cant seem to get anybody from dsmstyle to come... I even offered free beer! Any other suggestions. I am willing to pay for a 2g stock mas if anybody knows of one around for reasonable. BTW this is my DD. So its kinda time sensitive : (

 

[spyderturbo007]

I'm guessing that you don't have a friend that could lend you an ECU to try? Electrical problems are the worst, especially when you short something out. I would suspect that the problem lies with the ECU, but it is hard to tell over the internet.

 

[eclipse93b]

I dont know what to think! In my 1g gsx my ecu blew because it shorted from a voltage spike from a faulty alternator. The car just killed and didnt run at all. I dont want to throw down a ton of money here and I cant seem to find anybody in the area to lend me a hand. I will take the ecu out today and check the circuits for burns or corrosion. I just want to get this damn thing working again.

 

[spyderturbo007]

I understand your dilema, especially when your DD goes down. Pulling the ECU would be the first thing I would do. It's easy and quick. I would also advise you to take a couple of really good, hi resolution, pictures of the board and post them here (or link to them if they are really big). Some of the guys here are masters of the ECU circuitry and can normally tell you immediately if there is a problem with the board.

 

[eclipse93b]

Thanks for the replies to everyone.

I pulled the ecu and everything looked normal, however, it was fried (I swapped it with a new one and the car runs great!) So, for future reference if anybody has a similar problem, it IS THE ECU.

 

[LessIsMore]

I've been dealing with this same problem for a while now. 95-96 ecu 4G63 car which throws the following codes,

p0110 Intake air temperature circuit
p0100 Mass or Volume air flow circuit
p0105 Manifold absolute pressure/barometric pruessure circuit

I've replaced the MAS and the main grounding wires on the car. I've also torn the wiring harness down from the MAS harness all the way to the firewall and couldn't find a short. There is no signal voltage at the MAS harness for the IAC, MAP, and VAF sensor, when it shoud be about 5 volts.

I've tried clearing the code and it comes back after a few seconds of driving accompanied by an audible click from the computer.

I'm hoping its a fried computer so I can finaly get rid of this code and pass emissions. Where's the best place to get a new computer? Should I bother with a refurbished unit from a place like Autozone?

 

[eclipse93b]

It is the ecu. Set up an add on dsmtalk.com or here (thats what I did) and I got 6 or 7 offers from other dsmers most were GST ecu's.

97-99 GST/GSX ecu's will work with a 95/96 !HOWEVER! you will have to change your firing order (plug wires) and the CAS is inverted as well which changes the order that your injectors fire. Dont worry about the inversion because there are several people that run these ecu's that dont have a problem with it (its just not 100% efficient.)

The auto ecu will not differ from a 5spd, however a GST will from a GSX ( the gst has a speed limiter {governor} at 130mph).

Also for a non eprom you should see them sell between 100-170 and for an eeprom you should see ~250 bucks for those.

I hope what I learned with my car can be useful to you with yours.

Kyle-

 

[LessIsMore]

Well the car has a 1g head on it with a 1g CAS so the plug wires are already swapped, so going 97-99 would just bring the firing order back to stock.

Your post is very reassuring and I will go find an ECU ASAP.

Thank You!!!

 

[tallywacker]

Yep my ecu was doing that same crap when it died. Atleast you didn't buy any other parts during the diagnoses like some of us have