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2G Installing a 1g CAS in a 2g

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The 94-96 cars (correct me if I'm mistaken) have a separate cam angle sensor and crank sensor. Other years have them both in one unit on the passenger side of the head.

Here is where the CAS is located on these cars:
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Closeup:
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You'll first have to make a wiring harness to connect the 1gCAS to the cam angle sensor and crank sensor connector. (Link on how to make this harness: RRE Instructions) step 1 is to cut the wiring harnesses for both. Cut them so you have as much wiring as possible to work with as you have to route the wiring around the back of the motor. Here's where I cut the cam sensor:
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This is what the connector looks like for the cam angle sensor:
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Here's the whole pigtail I cut off.
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If you're still confused as to where these connectors are, they are both mounted on a metal bracket behind the motor by the firewall. Here's a picture of both pigtails mounted on the metal bracket:
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These are the connectors that go to the wiring harness:
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This is where I cut the crank sensor:
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Once you make your wiring harness, you have to remove the plug on the passenger side of the head where you are going to install the 1g CAS.

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To do this, you must remove the valve cover. Most of you have probably done this by now. Remove the spark plug wires, take out the spark plugs, and remove all the inside and outside bolts on the valve cover and remove. If you havn't taken it off in a while you may have to pry it open. Now would be a good time to get a new valve cover gasket set...especially if your old one is worn.

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Here is the motor with the valve cover off. You have to remove this cap to get out the plug. Just take out the two 12mm bolts.

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Here's the cap out and the plug out.

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Here's the camshaft without the plug. You can see a slot where the CAS will go into.

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Now, jack up your car. Take off the front driver's side wheel. Remove the plastic so you can see the crankshaft pulley. (I actually was able to do this without taking off the wheel, but taking it off makes it easier) Take a 1/2" drive (ratchet wrench) and turn the motor CLOCKWISE so that the motor is TDC. Basically there are marks on the cam gears that you want to point towards each other. The mark on the exhaust cam gear (towards the front of the car) should face 3:00. The mark on the intake cam gear (towards the back of the car) should face 9:00. Shown below:

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Now you have to set the 1g CAS to the right position. I can't seem to find the right words to describe what I want to say, so I'll do my best. But on the cas (shown below) the slot has one notched side. Also, the circle under it has a notch in it. You want to match up these notches.

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Once you've lined this up, attach the cas to the camshaft in the slot at the end. Re-install the cap over the cam with the two 12mm bolts and torque to spec. Bolt the cas to the head. Make sure the bolts are in the middle of the slot for now. In the picture below, it's at the end, but you should have it in the middle to start.

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Now go ahead and put the valve cover back on, and put your spark plugs back in. Now to use this cas you have to reverse the order of the spark plugs. From left to right, your cylinders are 4-3-2-1. The normal setup of spark plugs into the coil pack from left to right is 4-1-2-3. You need to reverse this so the order on the coil pack is (from left to right): 3-2-1-4. In DSMLink make sure "Invert CAS" is selected. I'm not sure how to do this without DSMLink, so someone please post up if you know what to do. Connect your wiring harness to the new 1g CAS and to the crank angle sensor and cam angle sensor on the wiring harness.

Now you have to set base timing again which should be 5 degrees advance. You will need to use a timing light. Follow proper directions for using a timing light. To adjust timing, simply loosen the bolts on the cas so you can rotate it. Rotate clockwise to decrease timing, and counterclockwise to add timing.

Now you're done!!
 
This sounds so easy. I have to recheck but I’m pretty sure that plug wires are in that order already. This will help a lot hugely BIG
 
Basically a 95-96 ECU is expecting a signal inverted from what the 1G CAM position sensor gives. If you don't invert the signal with ECMLink, or by building an inverter into the cable, you need to fix two issues.

1. Invert the coil pack trigger wires - or change the order the plugs are connected to the coil pack.
2. Re-sequence the INJECTORS

You don't have to re-squence the injectors just to get the engine to start, but if you don't - it won't run very smooth as you will be shooting fuel at a closed valve.

Justin
 
It’s all ready to go just need a 1g CAS sync cas/crank

What’s the OEM part number I’m looking for???
 
Remember that the RRE/Magnus/Etc. wiring instructions for these were done about two decades ago.

This is now just a plug-and-play wiring proposition thank to Brad @ Sheridan Connectors who started making harnesses for this swap back around 2008-2009 along with bringing a lot of other wiring connectors to market for these cars that we previously had to source from junk harnesses.

http://connectors.sheridanengineering.com/HAR-1G2G95.htm (for 1995-1996 cars)

http://connectors.sheridanengineering.com/HAR-1G2G97.htm (for 1997-1999 cars)
 
Rather than use the harness, couldn't you just leave the crank sensor alone and give the 1g cam sensor its +5, negative, and run one wire direct to ECU pin 88?
 
Rather than use the harness, couldn't you just leave the crank sensor alone and give the 1g cam sensor its +5, negative, and run one wire direct to ECU pin 88?

yes you can just use the 1g cam sensor for just the cam signal.

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Uuuuh, so... The ignition (spark) timing is based on the crank signal. If you don't care to adjust "mechanical" ignition timing, then yes - Just keep the crank sensor on the crank for a fixed "mechanical" timing. IMO - fixed mechanical timing at the crank is more accurate. A crank signal from the CAM has some additional mechanical noise introduced through the timing belt stretch. Using a 1G CAS for crank timing, you can mechanically manipulate the ignition timing. This is basically "lying" to the ECU

An adjustable CAM signal is really not desirable. Note how Mitsubishi does not use adjustable CAM sensors on 95+ cars. The CAM sensor signal is for the ECU to get the injector "sequence" correct. As long as the relationship between the cam signal and crank signal are within a reasonable range, and not an "inverted" square wave, the sequence will be correct. If you crank the 1G CAS +/- too far out of wack, with a fixed crank signal, then the injector sequence will be whacko.

(BTW - I made the original diagram that Dusty provided over 20 years ago based on information from Magnus)
 
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If you are you referring to the +/- adjustable range of the 1G CAS, somewhere in the middle is fine. If you have an o-scope and two probes, you could "align" the crank signal from the CAS with the crank signal on the crank. As long as its close, you should be fine.
 
It's interesting that you could mess with the injector timing independently like that. Could be a 'free mod' to help lazy injectors that need a lot of deadtime. Aside of that I can't think of any advantage.

I almost prefer to do it the way of using the crank sensor, as that's put at 5* and left alone either way. This allows you another adjustment, as moot as it could be.
 
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It's interesting that you could mess with the injector timing independently like that. Could be a 'free mod' to help lazy injectors that need a lot of deadtime. Aside of that I can't think of any advantage.

I almost prefer to do it the way of using the crank sensor, as that's put at 5* and left alone either way. This allows you another adjustment, as moot as it could be.
That's just it!, It's not going to change the timing of the injectors. Timing (spark and injector) is based on crank signal. The sequence, or "firing order" (1324) is based on a combination of the crank and cam signals. If the crank signal is inverted, or shifted too far out of alignment, the firing order will rotate by 90deg (4132) or 180deg (2413).

Now throw on top of that, There are two coil packs, (not 4) you can warp your noodle pretty good knowing two spark plugs ignite at the same time - but only one piston fires.
 
So what you're saying is if the signal is from the crank, the cam sensor is then only there to make sure things aren't 180 off. The cam sensor could be put right in the middle of the adjustment, or clocked 10* either way, and nothing would happen either way.
 
I might be asking a stupid question but has anyone done a write up re-sequencing injectors?
If so should link it to the thread would be perfect. I've got a 98 harness, 95ecu with 6 bolt bottom end 7 bolt head. Got the car to run but like Justin stated in one of his posts.....not well. Breaks up free revving but will idle all day no problem.
I dont have ecmlink to invert the signal or anything like that...
 
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