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6 bolt swap in 2g advance timing wont go under 10°

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97eclipsegst4g63

Proven Member
36
0
Sep 1, 2015
Livingston, Louisiana
Okay so i finally got a obdII scanner software an hooked it up today. Well my advanced timing was jumping between 11°-13.5° at about 1000 rpms. When i got my brother to turn the cas it would only go down to about 10°-12.5° at about 1000rpms. Could it possible be the software because when we use the timing light we can get it to about 5°. Also would it be save to drive it as a dd with the timing that high?? What would it damage? Depending on this car to get me back an forth to work probably about 50 miles a day. I also have a p1105 trouble code poping up i read this is a feul pressure solenoid. Is it dangerous to drive it with that code on?? Thanks in advance for any information!!
 
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It is supposed to be 5* btdc, are you saying that the best you can get it to is 10-13.5* atdc? or btdc?
Another way I read was to try to match the timing light/cas to what the scan tool/ecu is reading out.

I have never tried these methods (just read about them here) so take it with a grain of salt.
 
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Pretty much a guesstimate based on how far past tdc it is. I just saw another thread of yours stating your motor is freshly rebuilt so I don't want to say what is safe or not as I have never personally broken in a rebuilt motor.
Sorry man, I keep trying to search but not a lot of options without ecmlink.
 
You guys are confusing base timing amd ignition advance. The ecu does not report base timing, it doesnt even know where the cas position is. Ecu reports a position relative to a fixed point which is base timing. Setting the cas has nothing to do with what ecu reports. You use a timing light. Of course to do this ecu control is removed.
 
If memory serves 2gs still have a ground check connector. I never looked for the procedure since 2gs come stock with fixed base timing.
 
Setting base timing is really just aligning the ECU commanded advance with the actual crankshaft position.

The ECU assumes alignment when it reports a value to your datalogger but cannot check it's accuracy directly. As I'm sure you're aware, timing jumps around quite a bit at idle, its one of the most important ways the ECU tries to control idle speed.

The 2G cars don't have an adjustable CAS; factory logic assumed that base timing would always be correct and never change once base timing was set at the factory. Dealerships have MUTII scan tools that allow them to place the car in fixed timing mode and check it. I say "check it" because unless you are using a 1G CAS, that's all you can do. Dealerships were instructed to check integrity of the crank damper, timing tin and both position sensors and replace parts as necessary in the occasion that alignment was off by more than 3 degrees either way. I don't know about you, but 3 degrees is too much tolerance in my opinion.

All of our ECUs contain logic to check alignment of the signals from the CAS and CPS, and that alignment determines which coil fires. The 1G CAS provides both signals, unlike 2Gs which have separate sensors. That's why 1Gs have an adjustable CAS, otherwise they would have no way of correcting a misaligned sensor. 2Gs will often cut spark when the t-belt slips, although it rarely saves the engine.

In order to set the alignment (set base timing) the ECU must be not be allowed to change timing from a fixed value. Then, using the fixed timing value as a reference point, the timing light on #1 cylinder should flash to show that value being pointed at by the timing mark at the crank. Unless you have a way to make the ECU fire at the same timing advance on each revolution of the engine, you don't want to mess with anything.
 
Okay so i finally got a obdII scanner software an hooked it up today. Well my advanced timing was jumping between 11°-13.5° at about 1000 rpms. When i got my brother to turn the cas it would only go down to about 10°-12.5° at about 1000rpms. Could it possible be the software because when we use the timing light we can get it to about 5°.
1) You can't use any adjustment of the timing light, it must be set to zero.
2) Since you've screwed with the 1G CAS, you now have no idea what the actual ignition advance is.
3) The values you see reported on the logger are what the ECU is programmed to use at that engine speed and load, no amount of twisting the CAS is going to change what the ECU is programmed to do. Values went down because that's the amount the ECU is allowed to change the timing at that breakpoint on the ignition map, after you over-advanced the timing with turning the CAS.
4) Your next step is to find a way to put the ECU into fixed timing mode. Unless you have a friend at the local mitsubishi dealer, you are going to have to spend money.
5) Once you get the ECU into fixed timing mode, you turn the CAS and get the timing mark at the crank to line up with the 5 degree btdc mark. Do not adjust the timing light, or you'll be off by however much you do.
 
1) You can't use any adjustment of the timing light, it must be set to zero.
2) Since you've screwed with the 1G CAS, you now have no idea what the actual ignition advance is.
3) The values you see reported on the logger are what the ECU is programmed to use at that engine speed and load, no amount of twisting the CAS is going to change what the ECU is programmed to do. Values went down because that's the amount the ECU is allowed to change the timing at that breakpoint on the ignition map, after you over-advanced the timing with turning the CAS.
4) Your next step is to find a way to put the ECU into fixed timing mode. Unless you have a friend at the local mitsubishi dealer, you are going to have to spend money.
5) Once you get the ECU into fixed timing mode, you turn the CAS and get the timing mark at the crank to line up with the 5 degree btdc mark. Do not adjust the timing light, or you'll be off by however much you do.
I dont have a adjustable timing light.. an so in order to set advance timing i cant just use the timing light an turn the 1g cas until the mark reads 5*? Id have to set the ecu into fixed timing mode an then use the timing light an turn the cas until it reads 5??
 
1) You can't use any adjustment of the timing light, it must be set to zero.
2) Since you've screwed with the 1G CAS, you now have no idea what the actual ignition advance is.
3) The values you see reported on the logger are what the ECU is programmed to use at that engine speed and load, no amount of twisting the CAS is going to change what the ECU is programmed to do. Values went down because that's the amount the ECU is allowed to change the timing at that breakpoint on the ignition map, after you over-advanced the timing with turning the CAS.
4) Your next step is to find a way to put the ECU into fixed timing mode. Unless you have a friend at the local mitsubishi dealer, you are going to have to spend money.
5) Once you get the ECU into fixed timing mode, you turn the CAS and get the timing mark at the crank to line up with the 5 degree btdc mark. Do not adjust the timing light, or you'll be off by however much you do.
An what do you mean now that ive turned the cas i have no clue what the ignition advance is?? Sorry for all the questions im pretty new to these cars
 
I have not used the method described in the link you posted, but if timing is indeed always 6 degrees while cranking, it would work. Personally, I'd rather do it as the FSM describes, I'm surprised if there's no temperature offsets for cranking ignition timing. The FSM specifies a warm engine, but that's probably just so the engine keeps running instead of stalling out when timing is locked at 5 degrees.

The values for commanded timing advance reported by the ECU to your logger are only correct if base timing is correct, again the ECU assumes it's set properly and has no way of knowing if the CAS is sending the signals too early or too late. On a car that is heavily modified or one that's being tuned from scratch on a dyno by a pro it would be less important to have correct base timing. For one tuned remotely, or by an owner seeking help online, it is pretty important.
 
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