ok my Megasquirt has been throwing me massive curveballs, and as it is Im jewish, which means right off the bat Im at a disadvantage.
/end bad joke
at the moment Im stuck on figureing out how exactly Im supposed to utilize my factory crank signal to tap in to the older ignition modual. from what Ive gathered, (and its never this easy)
the crank trigger wire can befound on my ecotec idi connector, the wire is then routed to the newer control modual, which should then have two outlets for my coils correct?
also Im guessing this means bye bye IDI cover seeing as how it is not really going to let me stuff the older modual in there any way, and not to mention the thing has weak ass coils
it just doesnt make any sense, I mean I know there are other things to worry about like the bypass and proper refrencing of the signals, but for the most part. Im thinking that thats about it.
I really hope this works out. becuase I cant wait to toss my factory idi setup, for a nice set of msd coils and some meaty ass wires.
"
boobs now with Riboflabin"
could you post your question more clearly? I would like to help, but im having trouble filtering through your rant. what exactly do you need to know?
M90'd Built LGO-15 PSI
http://webstarts.com/quadper4mance
Im trying to wire my ignition for my megasquirt.
in order to do so, you need to swith to the older obd1 modual's which didnt have ion dectecting (basicly emission BS) which is a secondary signal for the processor to compute. the MS can not break that signal down, so you have to run the older modual, which will take the factory crank signal and make it useable for the megasquirt to process and produce a useable IGN signal.
I understand the theroy but I need to under stand the process
"
boobs now with Riboflabin"
Okay then, heres how it works...
The ignition module you have on your car from the factory works as a relay point. First, the crank position sensor sends its signal to the ICM. Next, that signal is routed out to the vehicle ECU. There, the ECU determines what advance or retard it wants, and sends that Timing signal back to the ICM. From there it is routed to the respective coil to fire plugs at the appropiate time. With this ICM, your computer directly controls each coil.
To use MS, you MUST do a retro-grade to an older ICM. These older ICMs are alot smarter than the new ones, becuase they take the Crank Position signal, and gererates its own Timing signal for the coils. This is set firmly at 10 degrees. The car will be able to run without the ICM even hooked to the ECU. Next, the crank position signal is also routed to the ECU. on the older cars which used this ICM, the computer would only calculate the Advace or Retard, and send just that to the ICM. remember the ICM is already running 10 degrees of advance, but if the ECU wants more, it sends a signal to the ICM to augment the timing by lets say 12 more degrees, for a total of 22 degrees. This is how the MS is set up to work. It will not generate its own base timing, but will augment the original timing. This is becuase it is using the HEI-7 Mode.
So, what you need to do, is first pin out your New (older) ICM. Find the Bypass, and EST lines. Those need to be routed to MS on the MS's Bypass and EST lines. you may "jump" onto the factory wires at the the ICM and ECU, becuase this will save you from running brand new wires to and fro. for a write up on how we do it with the Quad 4, check this out.
http://www.quadper4mance.com/ms
remember it will be different for you becuase you have a ECO, but the principle is the same. Once you figure out what we do, you can apply it to your car, and make the changes nessesary. lemme know if you have any other questions.
M90'd Built LGO-15 PSI
http://webstarts.com/quadper4mance
Remember Jason... you are still going to need the your stock ICM hooked up if you want the car to be able to shift correctly. You don't "need" the coils connected, just the ICM.
Also, the crank sensor wires should be yellow and purple. IIRC, the wiring colors are backwards (i.e. if reference high on the stock ICM is yellow, then the reference high is purple on the older ICM plug). I would check the Haynes or Chilton manual to be sure on that.
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"Youth in Asia"...I don't see anything wrong with that.
Good point Brian.
Also, you may wanna get a subscription to www.alldatadiy.com for 25 bux. you can get the schematics to both cars, and compair notes. Haynes is okay, but they dont list the ECU and ICM pin numbers or anything, so you/ll be guessing with color codes. That may or may not work ,cuz sometimes there are multiple wires with the same color on the same connector,and its gets iffy.
M90'd Built LGO-15 PSI
http://webstarts.com/quadper4mance
I know the Haynes tells you the function of each wire color (not 100% sure if it shows the pin #). On the 2.4L, there aren't any repeated colors on the ICM plug (there are 2 purple, but one is purple and the other is purple/white. Megasquirt has a write up of how to wire the old ICM, and if you are using a 2.2L/2.5L ohv ICM, which I would assume since you have an ECO... then when looking at the ICM with the plugs in front and the coils behind, the pin lettering goes from right to left.
I was able to use just the Haynes, the megamanual write ups, and a little online help from a fellow JBO member. All of the gauges work except for the coolant temp (since I don't have it hooked up yet).
Also, if you can get the IAC to work correctly, please let me know. I tried all of the tricks they mention on msefi, but still nothing. I'm curently running the IAC off of the J-body ECU...It's far from perfect, but it gets the job done.
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"Youth in Asia"...I don't see anything wrong with that.
Hmmm, the crank sensor wires are opposite of that of the older icm? This may be the reason why I am getting no rpm signal to megasquirt. I put a spark tester on it, it is sparking, but no rpm signal while cranking on megatune. And even more odd, when I crank for more than a couple seconds, megatune looses connection with megasquirt, all the gauges go blank, 3 of the lights on the bottom of megatune turn on, the 3 on the right handside, knock, and two others. I am not sure if those lights have any significance, as I dont even have the knock sensor interfaced into megasquirt.
Are you running MS or MS-II?
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"Youth in Asia"...I don't see anything wrong with that.
Fst Cavy wrote:Hmmm, the crank sensor wires are opposite of that of the older icm? This may be the reason why I am getting no rpm signal to megasquirt. I put a spark tester on it, it is sparking, but no rpm signal while cranking on megatune. And even more odd, when I crank for more than a couple seconds, megatune looses connection with megasquirt, all the gauges go blank, 3 of the lights on the bottom of megatune turn on, the 3 on the right handside, knock, and two others. I am not sure if those lights have any significance, as I dont even have the knock sensor interfaced into megasquirt.
That's a good indication that you aren't supplying MS with power that is "Hot in run/crank/start." It is also possible that the bypass might not be hooked up correctly. How do you have it wired?
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"Youth in Asia"...I don't see anything wrong with that.
Im gonna have to break this all down, but for the most part it is coming together. im having a bit of trouble understanding how the orignal ICM stays in place and reads the siganls if the older ICM is running the timing modual.
Im gonna have to do some reading thanks guys. this site really is the best.
"
boobs now with Riboflabin"
Jcavi wrote:Im gonna have to break this all down, but for the most part it is coming together. im having a bit of trouble understanding how the orignal ICM stays in place and reads the siganls if the older ICM is running the timing modual.
Im gonna have to do some reading thanks guys. this site really is the best.
It's not too hard. The J-body ICM just needs to "think" it is controlling spark. I made the mistake of cutting more wiring than I needed to.
First, you don't have to cut any of the wires going to the Jbody ICM. You do, however have to tap/splice into the wires
-Crank sensor high (yellow or one of the purple wires)
-Crank sensor low (vice versa)
-12v Power (pink)....(I cut this wire and ran it straight to the older ICM instead of splicing it, because I feared the gauge of the wire was too small to split between the two ICM's)
To power the other things though, I took a thicker 12v "Hot in run/crank/start" wire from underneath the dash, and extended it into the engine bay with 12 gauge wire. I used this wire to connect to:
-Megasquirt
-Injectors
-Jbody ICM
As long as the Jbody ECU can interpret what the rpm's are (aka: why you have the crank sensor wires still hooked to the Jbody ICM), then you at least have the capability to shift between gears. In order to get the shifting to be like normal though, you have to let the Jbody ECU also know what the throttle position and possibly MAP too is...I would just leave the GM map sensor alone. People told me to splice the megasquirt TPS signal wire into the stock TPS signal wire. That didn't work for me, though. I run the TPS signal and +5V reference wires to both MS and the Jbody ECU... and the ground wire on the TPS, I run to where I grounded everything else.
Edited 1 time(s). Last edited Sunday, September 09, 2007 5:34 PM
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"Youth in Asia"...I don't see anything wrong with that.
^^
Makes sense. Do you have your car running currently that way? All in all, how does it run with the fuel&spark?
Blew it up, build numbers coming soon
Here
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I do not know about the jbody wiring, but the crank wiring needs to be reversed. Yellow to Purple, Purple to Yellow. You will get werid readings on MS, but you will get a reading on it. Mine would fire every so often. If you need any other help with MS+Ecotec lemme know
The L61 Powered Fiero
98redcavz24 (LD9Stunner) wrote:^^
Makes sense. Do you have your car running currently that way? All in all, how does it run with the fuel&spark?
start up is a bitch (courtesy of the "jury-rigged" IAC)...but other than that it runs pretty smooth. I haven't had a chance to wire the knock sensor yet, so I have been running premium . The car has been running great for over a month now. It has survived three 120 mile trips on the setup so far (knock on wood)...and I'll be driving it even further in a couple weeks.
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"Youth in Asia"...I don't see anything wrong with that.
Brian, I have been through the no power during crank already, that was the first issue, thought the one i had was good, but it wasnt, so I switched to the fuel pump relay, and that works, it gets power during ign/run/crank. With that not being it, I just dont understand the megatune going dead, it makes no sense. Sometimes it can crank for 10 seconds before it goes out, but it does go out.
Ok so I have been reading and Im running into some problems due to the fact that I dont really understand which part is the ICM. is it that mdual the actually plugs into the coil pack cover thing.
also what am I looking for on the older unit., and is there anyway to run code free?
"
boobs now with Riboflabin"
Yes. The ICM is the device that the wiring going to your valve cover plugs into.
...and taking what DICE posted:
Like I said earlier, if you are looking at the older 2.2L ICM with the plugs in front and the coils in back, then the pin "lettering" goes from right to left
Under Red
This is the far left plug for the 12v power (pink) and ground (black)
Under Creen
This is the far right plug (hence only three wires). The yellow wire on your Jbody ICM should go to the purple on the older ICM and vice versa. The middle wire "B" isn't needed, so just leave it alone.
Under Blue
And by process of elimination, these are found on the middle plug. They should be wired to however megasquirt tells you to wire it (I have MS-II, so mine is a bit different). I don't know if Megasquirt has a bypass internally, but for us MS-II owners, you have to wire a relay to make the bypass. Also, the "C" pin should be ignored, unless you were going to use an external tach.
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"Youth in Asia"...I don't see anything wrong with that.
Here maybe you guys can help me out with my current issue
http://www.j-body.org/forums/read.php?f=2&i=395579&t=395579
I dont know if you can run code free, as I dont have this in a jbody. But the ICM you want is from a 93 cavailer, 94 switched to OBD2.
How the OBD1 ICM works is like a bypass. The only thing the ICM does is control spark below, I believe, 500rpms. After that the 3 wires going to Megasquirt are used and MS controls the spark pass that. The newer ICMs dont have this bypass and are more like a complete relay, in my words they are 'dumb' and dont do any computing.
The picture I posted is of a 93 and works great. I believe you will not have to cut any wires from your stock ICM. The only thing you need to take away from the ICM is the Crank Signal. I do not know if you can splice it but Id take a Check engine light over a odd RPM signal.
The L61 Powered Fiero
I'm currently in the process of wiring a ms-II to my 2.2 2006 cobalt. I'm wondering what method some of you used to wire the obd 1 icm into the cassette peice for the coils. On mine the icm plugs straight into it with no wires between the coil assymbly and the icm. I'm guessing it's the same on other ecotecs.
Okay, well since i've been here on a 2.4l i'll put my in my .02.. I didn't read this whole post but i'll add what i did when i had my car running spark on a 2.4.. MS1 v3.0 squirt and spark.
Old style ICM Plug (2.3 quad four ICM)
PIN L- (pink/blk) is power, needs power in run, crank, and acc.
PIN E- (white) is EST output, and goes to PIN 36 on the megasquirt board
PIN B- (purple) goes to CPS
PIN C- (yellow) goes to CPS
PIN F- (white) instrutment panel tacho
PIN K- (blk/white tracer) Ground, you figure this out
PIN G- (lt blue/blk) not used with MS
PIN H- (purple/white) Reference pulse input HI, goes to pin 24 on MS
PIN D- (tan/blk) Ignition bypass goes to pin 6 on MS, but should only be hooked up after you get the car running correctly On base timing
PIN J- (blk/red) reference pulse LO.. ground with pin 11 on MS
Thats exactly how I had my car hooked up and had no problems with it... everything I had to go with it is now with FST cavy, and its really hard to diagnois something over the phone or online. Basicly just make sure you have everything hooked up correctly and it should work..
I'm guessing you used a cassette type coil setup? how did you wire the obd1 icm to the cassette? My stock icm plugs right into the coil assymbly. Guess I'm going to have to find a connector that'll fit in there and rig it up...
Also I'm guessing your ms car is a manual tranny? I'm worried about splicing my stock icm in with the obd1 for a shift reference as it might mess with the ckp signal. The more and more I think about it it seems like it would be a good idea to swap to a manual trans before wiring the ms up.
