1989 Electra T-Type Trouble Codes 22 & 41

[jiveabillion]

I am getting trouble codes 22 & 41. 22 is TPS voltage low and 41 is Camshaft Position Sensor. I replaced the TPS and adjusted it to the correct voltage, but trouble code still shows up. Camshaft Position Sensor tested ok. I dont want to have to take the timing cover off to change the camshaft magnet if I dont have too. Shouldnt the car refuse to start if the camshaft sensor is unplugged? My car starts right up if even when it's unplugged. The guy at the auto parts store said it might be the computer. Im wondering what you guys think.

[HotZ28]

The 3800 will start and run fairly well without a cam sensor or with a broken magnet. If the camshaft signal pulse is not present during cranking, ECM/PCM signal logic begins sequencing injectors after two crankshaft revolutions or six pulses from the 3X reference signal. Code 41 is stored on the seventh pulse from the 3X signal and sequential injection begins in a random pattern. There is a one in six chance that fuel injection will coincide correctly with valve opening. If injection is off, drivability is affected only a small amount (slight hesitation).

[jiveabillion]

but why would I still get error code 22 after replacing and correctly adjusting the TPS to the correct voltage? What are the chances my ECM is bad?

[jiveabillion]

I am still having these problems. But now it stalls every time I start it after it has been sitting over night and give it gass after putting it in gear. I need more information on this if anyone has any to share. thank you in advance.

[HotZ28]

Code 22 indicates that the TPS voltage was under 0.2 volts for 4 seconds when the engine was running. Check the voltage on the white wire at the TPS to see if you have a 5.0V reference signal from the ECM. Wiggle the wires at the connector to see if the voltage changes. Now, check the blue wire to see if you have .5V (or a little less) with the throttle closed, then measure voltage as you open the throttle gradually, up to WOT. The voltage should progress from .5V to somewhere around 4+V @ WOT. If you do not have the 5.0V reference signal from the ECM, suspect either the wiring from the ECM to the TPS or the ECM itself.

Have you checked the car for vacuum leaks? I use the propane method around all fittings & gaskets while the engine is at idle. If idle speed increases while testing with this method, you have found your leak.

Cold start or shutdown problems with a cold engine could also indicate a problem with the CTS. The CTS sensor tells the computer what the operating temperature of the engine is. When the engine is cold, it needs more fuel to operate correctly, and if it is cold enough, it will inject a large quantity of fuel to start the car. This is called Cold Start Enrichment and replaces the function of a choke.

The ECM also sends a 5V reference signal to the CTS sensor. As temperature changes in the coolant, the electrical resistance of the CTS sensor also changes. Start the engine, and check voltage. Record the voltage changes as the engine warms up to operating temp. i.e. 120, 140, 160 & 180. You should see close to the full range of voltage (5.0-1.0V) during this test. If it does not change from what you first measured cold, replace the sensor!

With all that said, did you ever check the cam sprocket magnet? Code 41 indicates that the cam sensor signal was not received by ECM for the last 2 seconds while the engine was running. All you have to do is remove the cam sensor and turn the engine over until you see the magnet in the hole where the sensor fits. If the magnet is missing or damaged, your injectors are firing at random and not in time with valve opening!

Would this cause the problems you are having? Yes, as well as the other items mentioned above. Codes will only point you in the right direction; it is up to you (or the technician) to properly diagnose the problem. Replacing parts that may not be defective, is not the solution!

[jiveabillion]

What are the chances that all these sensor problems are directly related to a problem with the ECM?

I would check the the magnet on the camshaft if I had a breaker bar or something to turn the engine with. I don't have many tools at my disposal.

[HotZ28]

All the sensors operate with a 5V reference from the ECM. You can check that and if all of them have the 5V, more than likely, the ECM is operating as designed. How the ECM interpets the sensor output, is a different story.

You could use the starter to turn the engine over if you have a "bump start switch" or you could use the ignition switch to bump in small increments until you see it.