Megasquirt no rpm
03-12-09, 10:37 AM
#27
Engine, Not Motor
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And you are SURE it's set to take input from the coil? It needs to be configured for Opto/Coil in, the XG jumper needs to be in place, and there may be one other thing I'm forgetting.
I'm out of ideas if you aren't getting a signal at the - of the actual coil. Maybe scope the output of the ignition conditioner on the 'Squirt board and see if you are getting a signal.
I'm out of ideas if you aren't getting a signal at the - of the actual coil. Maybe scope the output of the ignition conditioner on the 'Squirt board and see if you are getting a signal.
03-12-09, 07:01 PM
#30
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If it's detecting RPM from the stim, it's very probable that there is either a hardware or software misconfiguration. Throw the pics up, let's take a look! Which stim do you have? A JimStim or the basic stim? Send pics of both. We'll get you going.
03-13-09, 01:20 PM
#33
Engine, Not Motor
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Holy crap a 2.2. I've not seen one in years.
Of course, with a 2.2, half the stuff I suggested is wrong. There's no VR circuit and no choice but to run a coil pickup.
You have the wing diode jumpered under the board. Try cutting the jumper. That will prevent you from using the Stim, but is the proper setup for coil triggering.
Of course, with a 2.2, half the stuff I suggested is wrong. There's no VR circuit and no choice but to run a coil pickup.
You have the wing diode jumpered under the board. Try cutting the jumper. That will prevent you from using the Stim, but is the proper setup for coil triggering.
03-21-09, 05:25 PM
#39
ok i've got the dave cap installed
i'm getting very erratic idle rpms rangeing from 100-1200
ive tried all kinds of resistors from 10,22,33,and 47k. also 10k times 5,4,ect. in series,10 and 22,10 and 33.
47k is to much =no rpms
33 is to much
22 is not enough
3-10k not enough
4-10k to much
10&22k works but the spikes come in effect
i really need a solution i'm getting frustrated
on a good note it will run .when it does it revs to about 2500 then stalls
thanks for your help in the past and the future
i'm getting very erratic idle rpms rangeing from 100-1200
ive tried all kinds of resistors from 10,22,33,and 47k. also 10k times 5,4,ect. in series,10 and 22,10 and 33.
47k is to much =no rpms
33 is to much
22 is not enough
3-10k not enough
4-10k to much
10&22k works but the spikes come in effect
i really need a solution i'm getting frustrated
on a good note it will run .when it does it revs to about 2500 then stalls
thanks for your help in the past and the future
03-21-09, 07:29 PM
#41
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The FP terminal provides a ground when activated. Typical use is to use it to operate a typical Bosch style relay. The transistor driving this output is NOT designed to directly sink a fuel pump's current. The image attached is what they may look like....
-Mike
-Mike
03-21-09, 08:53 PM
#43
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I'm only vaguely familiar with the FC, sorry, I'm only very familiar with FBs and RX-8s! It appears that you have access to the raw power wires for the FP, I think. If so, I would source one of the abovementioned relays and use it to switch the FP. These are used by many, many MS users, are very reliable, are easily handled by the MS FP transistor, are cheap and are pretty much bulletproof. For all we know the stock FC relay could be a solid state device in the ECU or the stock relay coil draws too much current for the MS' FP relay switching transistor.
03-22-09, 10:22 AM
#44
Engine, Not Motor
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Don't bother trying to tie into the stock fuel pump wiring. Just run new wires and use a new relay, connecting it as it shows in the Megasquirt wiring schematic.
Now, your RPM jumping problem is noise. The Dave capacitor is supposed to fix these problems, as is a series resistor.
What value of Dave capacitor did you use?
Where is your Megasquirt grounded?
Have you tried the coil negative and the black test tach wire?
Now, your RPM jumping problem is noise. The Dave capacitor is supposed to fix these problems, as is a series resistor.
What value of Dave capacitor did you use?
Where is your Megasquirt grounded?
Have you tried the coil negative and the black test tach wire?
03-22-09, 12:13 PM
#45
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I have found the Dave cap to be of limited use with FC leading coils or the FB coils. Upon scoping the coil negative, a large amount of ringing was seen in the signal which was made worse by the Dave cap. As always, YMMV. A method that has worked for several people (myself included) is to temporarily place a linear (not audio!) taper pot, 100K, in series with the tach line. Change it's value until you get a good result then measure that value and replace the pot with a fixed 1/4w resistor of similar value. Aaron's ground reference is likewise very important - our cars are older and a new, dedicated ground for the MS is an excellent idea. Several smaller ground wires to the same location are superior to one large one; references and a link to a video from Bruce Bowling can be provided to explain this apparent non-issue...
03-22-09, 07:18 PM
#46
alright change of plans
i just bought error*s daughter board
also going to rewire the engine is the any thing up front that i need to know that i won't find in the manual
i know i have to remove the dave cap
btw i have about 8 or 10 seperate grounds coming from the engine to the MS
i just bought error*s daughter board
also going to rewire the engine is the any thing up front that i need to know that i won't find in the manual
i know i have to remove the dave cap
btw i have about 8 or 10 seperate grounds coming from the engine to the MS
03-27-09, 07:25 PM
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-Mike
03-28-09, 07:52 AM
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That sounds like a workable plan. Make sure that the engine has a large enough ground to handle the starter draw; our cars are getting a bit old and a lot of the stock braids, etc., are not in the best of shape. Once you assure a very good batt-to-engine ground path the next step is to run all your MS related grounds to the same point on the engine block. Very important is to be sure the sensor grounds go to this same spot; otherwise you will very likely get a measured-voltage offset insuring incorrect temp readings. The proper relays are extremely common; your local auto parts store will have them for $5-8 USD. This link http://parts-express.com/pe/showdetl...number=330-070 is an example. If you under the section entitled "The Famous Bosch Relay" on this page http://www.bcae1.com/relays.htm you'll find a pretty good explanation of what each terminal does and what's inside these critters. Connectors are easily available for these as well. You will find them with and without a mounting ear; have your mounting scheme planned out to purchase the right variant. Let us know how you do!
-Mike
-Mike