Well, I have been having problems with my car running rich, and idleing poor and have replaced numerous parts trying to solve the problem. I recently got access to a scanner and hooked it up. The question I have for right now is: I came upon an item that read ASYNCH: NO. What is this? Is it some sort of pulse between the two injectors? It always stays at no, and I was wondering if it should say yes. If so, does anyone happen to know what the problem could be?
Also, there was a couple of other test procedures in there for other things such as the 02 sensor, CTS, etc. I have already replaced every sensor that it had a test for, but went ahead and did them any way. But, the one for the CTS kind of has me puzzled. First it said to check it while it was plugged in and the reading should be within a certain range (I don't remember the exact numbers, but if I recall correctly it was 90-185), and it was in that range. Then it said to unplug it and jump the terminals and it should again be within a certain range (I think it was the same 90-185), but this reading was at 200.
Anyone have any ideas ? Thanks

 

The async reading NO is correct. This is a fueling mode where the injectors fire at a rate of 80Hz. And is only used when the PW gets small.

The shorted CTS connector reading 200 sounds correct. The temperature scale goes to 150 C maximum, but the issue with shorting a sensor is that the ECM can use a substitute value. What is being done is checking the wires to the ECM.

To check the CTS & IAT leave the vehicle cool off overnight. Then with the scan tool read the values. They should be at ambient. Then start the vehicle and note the temperature increase. The CTS should go to the thermostat/fan on temperature.

Make sure that the scan tool is in 'open' mode, not any of the diag modes. Then drive around some and note that the ECM does go closed loop and what the BLMs are. A value around 128 is OK. Above that is adding fuel, below that is removing fuel. If the CTS is OK, and the BLMs are high, then the O2 sensor is either getting outside air (exhaust leak), or is bad.

If the BLM is low, then the injector pod may be leaking. The O-rings that seal the injectors go bad after a while.

RBob.