96 Q45T ECU has no LED?

[wchai]

Hi All,

I took the ECU of my 96 Q45T out to check the code because my check engine light came on. I did not find any LEDs on the back of the ECU which I read about in some posts. Is my ECU different? Does anyone know a different way to check the code so I can fix the problem?

The car has about 98K miles on it.

Thanks in advance.

Wilson

[metaverse3]

Hi All,

I took the ECU of my 96 Q45T out to check the code because my check engine light came on. I did not find any LEDs on the back of the ECU which I read about in some posts. Is my ECU different? Does anyone know a different way to check the code so I can fix the problem?

The car has about 98K miles on it.

Thanks in advance.

Wilson

It is OBDII..there wont be any led's...you need an OBDII reader rather.. Fortunately, they are reasonable..look for the basic actron model at the local auto parts store..

[wchai]

Thanks for the tip!

[elwesso]

Autozone reads codes free!!!

[wchai]

I borrowed the Actron AutoScanner and received the following codes:

P0325 Knock Sensor 1 Circuit Malfunction Bank 1 or 1 SensorP0135 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)

I earsed the code once but the P0135 code came back. I haven't driven the car so don't know if P0325 will come back. In the past I noticed the car knocking when laboring (uphill) while temp is above 95. I always attributed to the California gas. I now think the O2 sensor might have something to do with it.

The car is always much slower when it's hot out. Maybe the O2 sensor malfunction triggers knock sensors which would cause the ECU to pull back timing?

[DAEDALUS]

The O2 is only a problem when the engine's cold. It will take longer, but eventually the O2 will function properly once warmed up by the exhaust gasses. It's the heater, not the O2 itself. Lots of older cars don't have heated sensors.When the coolant gets too hot the car takes measures to keep it from overheating, and these reduce performance. You can try replacing the O2 first, but I don't think it's related to the knock sensor code.

[wchai]

I erased both codes and went out for a drive up to 120. I also reconnected the Driverside front O2 sensor harness. Both codes went away and the car is back to normal.

The loaner O2 scanner from Autozone worked wonders. I will monitor the car for a few days to see if the codes will come back.

Thanks to everyone for your help. I really appreciate your feedback.

Wilson