Too Much Power All The Time!!!!!!!

[alienauto]

Now that I have your attention... Me and my buddy are having some electrical problems with a 90 Talon awd/t He bought it for $350 bucks and we got it to run after finding a ecu for it. The engine is sounding great but it wont drop below a 2000rpm idle and it wont go into boost it just hessitates... We have eliminated any vacume leaks and cleaned the throttle body to no avail. The weired thing is that there is power to some of the engine sensors with the ignition in the off position, we noticed this when we were putting in the battery in and the the boost control solinoid was clicking on. We then checked for power elswere and found that the maf and diognistic port also had power....! and that is just the stuff we checked. Another strange thing is that the car drops to a good idle and will go into boost with the maf unpluged... Im stumped... Oh and the car has a newer jdm motor in it if you all care....Please help!!! Thanks in advance.

 

[ASZRAEL1266]

could the MAF be bad? if you have a friend with a dsm try swaping the maf see if that fixes it

 

[Robby Camero]

Wierd!!!

Try taking the ignition switch appart and clean it. Might be some bad contacts in there.

As for the idle, a bad mas or bad mas connection could very well be the problem BUT what year did the ecu come from. A 91-94 ecu wont work in a 90. The mass wire is in a different ecu pin along with one other wire which I cant remeber right now.

Good luck

 

[92redman]

Sounds like the ECU is getting getting fed power when the key is in the off position. The computer uses some of its sensors like the one's in the MAF when the key is in the on position with out the car running, to make calculations for injector pulsewidth. The ignition does not feed the sensors, the ecu does which means your ECU is staying on.
As for the idle, If you don't have the right year ECU, that would probably explain it since like Robby Camero said, one of the MAF wires is in the wrong spot.

 

[Robby Camero]

Is it possible the ecu relay is stuck?

 

[alienauto]

is there anybody that could tell me what the numbers should read on the ecu? i think that the ecu is a 90 because the numbers match the one that i took out but who knows if the one i took out was a 90????

 

[92redman]

Like robby said, you could just have a bad relay. If it were me, I would make sure that there is no power at the ECU from the ignition feed. If there is power, you have something screwed up in the ignition circuit. If there is no power there, then I would check the ecu relay.

 

[Robby Camero]

Some info I found

http://www.ecanfix.com/~mdhamilton/ecuconversion.html

 

[92redman]

Why don't you tell us what you have tested so far, and what you have gotten when you did.

 

[alienauto]

I have a HOT wire in one spot going to the ecu when the ignition when is off. Should there be a hot wire there? the fuel pump relay also has a hot wire to it. thats where i'm at now.

 

[92redman]

Yes, and yes. The other wire on the fuel pump should be ground but have 12 volts when you check it against ground since the relay would be on the ground side I believe.