HELP my gst get back on the road please experts only needed

[95gstclipse]

Ok i have a 1995 gst here's the problem everytime i rev the car it dies because it cant catch idle.The check engine light codes say ,iat circuit malfuction,map sensor circuit malfuction ,mas circuit malfucton.Ive changed the map sensor ,also everytime i start the car the radiator fans turn on ; when i unplugg the maf the fans turn off(very weird)and there is no change to the engine when its unplugged.So i donrt think its my maf thats bad possibly a short in a wire somewhere maybe also my battery light and srs light is on i doubt these lights have anything to do with my problem just thought i bring them up.Any suggestions people.

 

[95AWD6Bolt]

1) Get a new ISC.

2) If there is no change when you unplug your maf, get a new one.



Also, what mods did the previous owner of your car do?

 

[ilikerice]

just a thought.. im a newbie also to the DSM world, so this will be a general suggestion.. Have you tried disconnecting you battery. Make sure everything is plugged up (map, maf and all your other sensors). Reconnect your battery and then start it up. Maybe you unplugged something while the car was running before and now the ECU is all confused now. This sometimes works with newer models with OBD2. So im not sure if this will work, but its a suggestion.

 

[Aceman]

Is your BOV recirculated?

 

[95gstclipse]

1) Get a new ISC.

2) If there is no change when you unplug your maf, get a new one.



Also, what mods did the previous owner of your car do?

Well it only has 16g turbo and front mont intercooler kit on it everything is stock.Idk if putting a different maf will solve the problem because the radiator fans should have nothing to do with the maf right?

Is your BOV recirculated?

Yes my bov is recirculated.

 

[JusMX141]

Well it only has 16g turbo and front mont intercooler kit on it everything is stock.Idk if putting a different maf will solve the problem because the radiator fans should have nothing to do with the maf right?

Fans running all the time is generally a safety feature tripped by the ECU when the coolant temp sensor goes bad. The ECU does not know how hot the engine is, so it turns the fans on all of the time.

That, or someone hot-wired the fans to be on anytime the ignition switch is on.

There's always the possibility that the ECU is fried as well.

 

[BelleauTsi]

I got the same problem with mine and found that the black wire (ground) at the mass air flow as a very poor ground. Just put an eye at this

And looking at the wiring diagram, you will see that this ground is splice with others sensor.

 

[95gstclipse]

Fans running all the time is generally a safety feature tripped by the ECU when the coolant temp sensor goes bad. The ECU does not know how hot the engine is, so it turns the fans on all of the time.

That, or someone hot-wired the fans to be on anytime the ignition switch is on.

There's always the possibility that the ECU is fried as well.

Ive already switch ecu's same problem and that wouldnt explain why when i unplugg the maf the fans turn off .I feel like people are not reading everything I've written in my orginal post .

I got the same problem with mine and found that the black wire (ground) at the mass air flow as a very poor ground. Just put an eye at this

And looking at the wiring diagram, you will see that this ground is splice with others sensor.

Hmmm thats a very good point thanks ill look into this that's the best piece of information I've been given and your new/lurker like me .

 

[BelleauTsi]

A big boost leak like intercooler piping poped off make quite the same thing and you can see that by unpluging MAF.

 

[untouchablecc]

I find it hard to believe that everything that controls your airflow is bad. Iat,map, and mass. It sounds like a classic case of boost leak. A pre turbo leak could cause and issue like that as well. There is probably one underlying problem causing this.

 

[95gstclipse]

A big boost leak like intercooler piping poped off make quite the same thing and you can see that by unpluging MAF.

I've already had a boost leak and fixed that and how can i see that by unpluging the maf , Im not sure what you mean?

I find it hard to believe that everything that controls your airflow is bad. Iat,map, and mass. It sounds like a classic case of boost leak. A pre turbo leak could cause and issue like that as well. There is probably one underlying problem causing this.

Well i agree that all these sensors cant be bad judging that I've changed the map sensor and its still saying its bad. Also i don't think a boost leak would cause the check engine light to throw those 3 codes correct me if im wrong.

 

[BelleauTsi]

The only way you can make the car running with a air piping remove is the unplug the MAF, if no engine will run really rich. If it a boost leak you should see your AFR very low

 

[Sp1kE]

I would have to suggest a ground aswell. Those sensors all share the same ground. They all join together just before entering the cabin on a 2g. Not sure where they actually mount to though? A 1g the sensor ground mounts to the center console metal frame... Maybe start by finding that grounding point.

 

[95gstclipse]

The only way you can make the car running with a air piping remove is the unplug the MAF, if no engine will run really rich. If it a boost leak you should see your AFR very low

Im not sure what it is your trying to say , but my car is running very rich.

I would have to suggest a ground aswell. Those sensors all share the same ground. They all join together just before entering the cabin on a 2g. Not sure where they actually mount to though? A 1g the sensor ground mounts to the center console metal frame... Maybe start by finding that grounding point.

Yea im leaning towards this ground issue you guys are bringing up is there anyway someone can post a pic of were the maf ground wire is and looks like that would really help thanks.

 

[BelleauTsi]

Im trying to say that if you have a large boost leak you engine will expect must more air (calculated by the maf) than he gonna received, and inject more fuel so running extra rich.
But keep in mind to check those ground to

Easy first check is to measure resistance with an multimetre from black wire (MAf) to battery ground, there should be no resistance

 

[95gstclipse]

Im trying to say that if you have a large boost leak you engine will expect must more air (calculated by the maf) than he gonna received, and inject more fuel so running extra rich.
But keep in mind to check those ground to

Easy first check is to measure resistance with an multimetre from black wire (MAf) to battery ground, there should be no resistance

I'm going to check that ground doubt its a boost leak because of the check engine codes.

 

[Sp1kE]

Yea im leaning towards this ground issue you guys are bringing up is there anyway someone can post a pic of were the maf ground wire is and looks like that would really help thanks.

Each sensor will have a ground wire. Most of the time black. They travel through the loom and meet in the harness just before entering the cabin. The wire continues into the cabin and will be bolted somewhere inside your cabin. If you are getting a code for all those sensors, that shared ground would be the first spot I would look. maybe someone can help where that ground wire is bolted to inside the car?

 

[BelleauTsi]

Yes that would not explain those codes
Just explaining the rich AFR theory

For the ground mine was bolted in the floor under the center console just under the fuel pump relay and ecu

 

[95gstclipse]

Yes that would not explain those codes
Just explaining the rich AFR theory

For the ground mine was bolted in the floor under the center console just under the fuel pump relay and ecu

Ok is it possible you can take a pic of it that would help?