This thread is for a 2006 Saturn Vue 2.2L engine with 103K miles and auto tranny. I installed a new coil pack as my gas mileage was really down. It picked it pack up form around 18mpg city to 24. I also replaced the Ignition Control Module. After a few days it started coding P0340 (Cam position sensor). It will clear itself after a few more starts. But then it codes again a few days later. This vehicle does not have a CPS as it reads off of firing cylinder 1 and 3. I turned it in as a warranty item and got another one. It did the same thing. I looked on my Autel Scanner and I did not see any learning procedure. Could it be a manufacturer issue. This part came from CarParts.com. BTW, I put the old one back on and it does not code. Meantime, I have gotten my money back and now have 2 ICM's.

 

Surprised you didn't check the plugs first.
Are you running OEM plugs?

The waste spark ignition systems in the Saturn engines are known to be finicky with respect to the ignition components used. Plugs are often the culprit wrt the P0340/P0431 codes.

You are not the first to experience strange behavior with what I assume is an off-brand ICM in the Saturns.

Seems a bit overkill to throw parts at it like that. That's based on only the information given.

 

The plugs were changed around 70k with NGK plugs. With the original ICM, there was no code. It only codes with the new ICM. I changed it only because i replaced the coil pack. I will probably replace it with the original ICM. It was more of I had a new one, why not use it. It appears the system does not like it. Since I only have around 30k on the plugs, I don't see them as the issue.

 

If the old ICM is trouble free, seems like the thing to do is put er back in.

Last week somebody bought a cheap ICM for an S Series and the outcome was, shall we say, worse than the original situation. Person went back, bought a GM ICM for the car, end of story. You usually get what you pay for. Not always, but more often than not for Saturn parts it seems to be true

 

Going back in as I am hitting the Post Quick Reply. Thanks for advice.

 

If you weren't experiencing misfires you kind of wasted your money. Ignition only effects MPG a very little. We did tests of standard and high energy coils and as for MPH it's slight to nothing. The only time ignition effects MPG is from misfires.
BTW You have a crank sensor.

Operation CHARM: Car repair manuals for everyone.
Home >> Saturn >> 2006 >> VUE 2WD L4-2.2L VIN D >> Repair and Diagnosis >> Powertrain Management >> Ignition System >> Crankshaft Position Sensor >> Description and Operation

Crankshaft Position Sensor: Description and Operation

CRANKSHAFT POSITION (CKP) SENSOR

The crankshaft position (CKP) sensor is a permanent magnet generator, known as a variable reluctance sensor. The CKP sensor produces an AC voltage of different amplitude and frequency. The frequency depends on the velocity of the crankshaft. The AC voltage output depends on the crankshaft position and the battery voltage. The CKP sensor works in conjunction with a 7X reluctor wheel attached to the crankshaft. The CKP sensor produces seven pulses for each revolution of the crankshaft. The pulse from the 10-degree notch is known as the sync pulse. The sync pulse is used to synchronize the coil firing sequence with the crankshaft position. The CKP sensor is used for ignition timing, the fuel injector timing, misfire diagnostics and tachometer display. The CKP sensor is connected to the ECM by a signal circuit and a low reference circuit.
pro multis · About Operation CHARM

 

But I saw a big increase in the mileage after replacing the coil pack. I was down to about 18mpg and went back up to 24. When I would use a certain route that round trip would take about 1/4 tank which I thought was a lot. Now it is back to about 1/8. So, I feel like it did make a difference. You also sent me something about the Crankshaft Position Sensor. I changed that when I first saw the code. I read it too quickly when it was the Camshaft Position Sensor that was coding.

 

Over how much time? No matter how you come up with your numbers if it wasn't misfiring you didn't need to replace them. Also your mileage has not changed except in your mind.