It's been a long time since I ran my car, its been sitting for many years with occasional startup. My car is a s4 t2 with a ms1 ecu.

1) I know it is going to run rough because of tuning issues, but I was worried when I looked at the dash and the rpm did not show and my car was at idle. Not the most smooth idle, but idling. I reved the engine and the rpm went back up. I have played with the wires at the cas, and it makes no diference on how the engine runs

2)my buzzer used to never come on before I let my car sit, but now the buzzer is constantly on. coolant level is good. I got rid of the fan switch on the upper radiator hose

 

The tach runs off of the trailing coil. The Yellow/Blue wire at this coil drives the tach. You could have issues w/the coil itself or this wire.

You could have air in your radiator causing the buzzer. If you pull the radiator neck cap off and place fluid in it and then open up the bleeder screw and nothing comes out then you have an air bubble at the top of the radiator. The bleeder screw should be opened up first and then coolant added to the radiator cap after removal and then fluid should pour out of the bleeder screw opening. The Brown wire to the coolant sensor could be cut and that too could cause the buzzer. If the sensor was removed and the item grounded out that would stop the buzzer if it were caused by the sensor.

And the buzzer could also be caused by the engine being reved beyond the rev line. And the oil,if low, could cause the same buzzer to go off. The other day another poster claimed his oil level was just fine. Another poster suggested that when the oil cooler opens up to receive oil from the engine that this pulls down the oil level and could cause the buzzer to go off, but until then, the oil level would look good.

 

Oh cool! So do I have this correct? The cas sends the signal to the coils to fire, but the tacometer gets the rpm from the coil output?? I have to see if I have any spare coils to use to test. If they are bad, would you recommend any coil upgrades? I know my friend has FD coils, but I think I remember doing a quick search and reading those use an external igniter

I removed the thermostat switch on the upper radiator neck. I thought it was just for switching the ac fans on when hot. Mine broke, so I just plugged the hole and have an open. I don't have ac. Anyway to fake that the sensor is there and seeing water?

 

The sensor for low coolant is at the radiator itself and has a Brown wire. The sensor at the thermostat neck is a different sensor (has a Green coded wire) and would not affect the buzzer.

The trailing coil might not be grounded to the fender properly and is in need of a good cleaning. You could also have a plug and or plug wire issue causing the coil to cut out as well.

Cas sends signal to ECU. ECU sends signal to coils.

 

Thanks for helping. I will have to double check the wires.