So, I've gotten the 2002 Saturn Vue running well with the 2008 crate motor which would normally go into a Chevy Cobalt. The crank sensor and trigger wheel was the main hurdle (detailed below, #6). Several other swaps from old 2002 motor to the new motor were needed.
Starting from the beginning, the 2008 motor slipped right in to the 2002 Vue, with no modifications to motor mounts or anything like that. New clutch (manual transmission) installed, no problems or changes needed. The new motor did not come with a brain, so I had to use the 2002 brain and wiring harness with this 2008 motor. this introduced some issues, as some of the parts have changed (like the MAP sensor, the throttle body, fuel rail, fuel injectors, and crank sensor / trigger wheel assembly). Some connectors were different on the 2008 would not fit with the 2002 harness... I will explain how I addressed these differences below
The parts that I needed to swap over to the new motor from the old:
1. Throttle body - the connectors were different on the 08, so I went with the old one
2. Injectors - the injector bodies were different than the 2002 injector bodies, but fit in the manifold, so my initial desire was to use the new injectors(the old ones were... old after all), the terminals were different, so I soldered the new connectors into the old harness. I ended up having to remove these injectors, and put the 02's back in, rewiring the old terminals back into the harness... so much for the new injector idea - the 02 brain just did not seem to play well with the 08 injectors.
3. MAP sensor... different sensor, different connector, different hole in the intake manifold. I tried using the new sensor that came with the new motor by splicing old connector into the harness, color to color, but ended up putting the old MAP sensor in the new motor - as with the injectors, I don't think the old brain knew how to handle this new MAP sensor signal. Since the MAP sensor hole in the 08 intake manifold was larger than the hole in the 2002 intake manifold, I needed to modify the old sensor to fit the new, larger hole. I simply slipped 4 suitably sized o-rings onto the existing rubber grommet on the mounting spur of the sensor, so it now fit snugly into the hole. Now how do I keep it from popping out? The 2008 sensor uses a bolt to hold the sensor in, where the 2002 sensor was held in with a twist of the sensor... which wasn't going to work in the new manifold. I simply used the 08 sensor bolt with a short section of vacuum hose as a spacer (10 or 15 small washers would also have worked), and a large fender washer next to the bolt head which pressed down on the top of the sensor when the bolt was tightened. I used Loctite on the threads of this bolt to prevent the assembly from coming out.
4. Fuel rail... I used the old fuel rail with the new motor because the new rail was different.
5. Coil assembly/plug "wires". The 2008 motor came with 4 individual coils... one for each cylinder, while the old motor uses a 2 coil system. Since the harness was already setup to utilize the two coils system, that seemed like the way to go. Making the old coilpack fit on top of the new motor was not very hard, and just a few adjustments had to be done with the bolts. No biggie
6. Crank sensor / trigger. This IS a biggie. The 2008 motor comes with a 58 tooth reluctor on the crankshaft, and a hall crank sensor... not at all compatible with the 2002 wiring harness and brain, since the 2002 motor uses a 7 notch crank reluctor and a magnetic pickup sensor. I bought an aftermarket crank trigger wheel, which mounts on the crankshaft pulley. The 7th notch is the "pulse notch" which apparently tell the brain where your crankshaft is in its rotation. That 'extra' notch should be to the LEFT of the 2nd notch right next to it when looking at the wheel on the motor. If this pulse notch is sitting to the right of the regular notch, your wheel is on BACKWARDS - I made this mistake initially. I made a simple L bracket to hold the crank sensor, and after reading through some Saturn forum threads, I set the wheel to have the pulse notch pass under the sensor 70 degrees after the engine (#1 cylinder) passed top dead center. When I tried to start the motor using this 70 degree spacing, the motor barely ran, giving the classic signs of "wrong timing". After a couple days of this wrangling with differing degree spacings (and having the wheel on backwards), I decided to un-seize my old 2.2 motor so I could spin the crank and look through the crankshaft sensor hole myself to see exactly what the spacing of the sensor should be. After taking off the old head and freeing up all the eaten valves and piston parts from the destroyed motor, it spun by hand - yay! First I turned the motor to TDC for #1 cylinder. This is easy, because the crank pulley has a single timing notch on it which corresponds to a line on the block when number one cylinder is at top dead center. Quick look into the sensor hole shows there are no notches under the hole at TDC. Now, using a 6 inch circular protractor, I spun the crank clockwise until the 'extra' notch was centered directly under the crank sensor hole. This is the point after TDC where the brain wants to get it's signal from that extra notch. Going back to the pulley, and measuring carefully with the protractor, I found that the pulley had moved 57 degrees past the TDC line. So that's it - the pulse notch (extra notch) is supposed to pass under the sensor at 57 degrees after top dead center. I went back to my Saturn, and changed the trigger wheel so that the pulse notch passed under the center of the sensor at 57 degrees ATDC. The motor started right up and ran smoothly. I did my 50 mile motor break-in drive shortly thereafter, and had no problems throughout the entire 50 mile drive. I changed the oil, then did some diddling with the sensor distance from the trigger wheel, and found that (with the motor running), the brain didn't really care much how far away the magnet on the sensor was from the wheel... works the same from 1/16 to 1/2 inch away - it does seem to care if you get it too close to the pulley though, with it's 3 protruding steel 'spokes', so on top of the 3 'spacer' washers I used between the pulley and the wheel, I angled the sensor away from the pulley perhaps 10 degrees - it looks a little funny not being exactly centered over the trigger wheel, but it runs right.
This first pic is from when I had the wheel on backwards, but is representative of the setup. The second pic is my l bracket (made very secure with loctite) - the third pic is of someone else's setup, clearly showing the 'extra' notch to the left of the 'regular' notch, as it should be.
Hope this helps anyone who plans on putting a newer 2.2 ecotec motor into an older Saturn or Chevy - it's been an adventure
- wheel 3.jpg (186k)
trigger wheel.jpg (423k)