Hello,
I was wondering if anyone knew what causes the motor to cut out at certain boost levels. Like my stock 89 2.2 daytona cuts out at 14 pounds of boost. Is there some kind of sensor that causes the fuel to cut or what??
Thanks DaVE

 

Ok I checked my local dodge dealer and the specialist said there was a sensor in the intake manifold and I checked mine and I couldnt find anything can anyone back this up??
Thanks Dave

 

Couldn't tell you what the actual name of the sensor is, but it's there to prevent overboosting your engine and grenading it. I saw the effects of running in an overboost condition on a 91 Daytona and it wasn't pretty, melted pistons fused to the cylinder wall and all that good stuff.

 

Haha I know what you mean Ive melted a couple my self. So then there is a sensor on the intake manifold? Thanks for the help.
Dave

 

Not sure if it's a specific sensor. I believe its a cut-off relay thats triggered by a signal sent by the computer. I think it reads when the MAP sensor reads too much pressure in the intake (boost), but dont take my word for it. It may be run that way and it may not... >_<

 

yea, Im not sure what causes it either but im gonna do some checking. And hopgfully we will find it out.
Dave

 

The overboost protection is read off the map sensor. If it sees over 4.5 volts, the computer shuts off the fuel and spark. To fix this you need to get a zener diode from radio shack that is 4.5 volts. I would get a couple of diodes that are alittle less and more than 4.5 volts. (ie. like 4.4 volts and 4.6 volts). You then go to the map sensor wiring. There are three wires. You need to splice the diode between the map signal return and the ground wire ( You are not cutting the wires. only stripping back the insulation) . You have to put the diode on one way only. So install the diode temporarily then drive the vehicle to see if the fuel shut is gone. What the diode does is any voltage over the rated amount is bled into the ground circuit fooling the computer. You want to get as close to the 4.5 volts, because that's the computer's signal for full boost enrichment. Once the diode is in right and works, solder the diode to the wires, and insulate.

 

Thanks for the reply. We got it running ok for now but I will for sure check into doing that.
Thanks dave

 

Hey,
I am having a real hard time finding a zener diode that is 4.5, 4.4, or even a 4.3. You wouldnt happen to have one that I could purchase from you or know where i could find one. Local radio shack didnt have one.
Thanks dave