Hotshift13 Posted September 16, 2010 Share Posted September 16, 2010 Hey guys, I'm not really a new member but I've been gone a long time, and I couldn't remember my password. As you may have guessed I have done the Megasquirt upgrade. I love it, easy to put in the car and get up and running, Thanks to mobythevan's maps and usefull tips. Now heres my problem.... I drove the car and tuned it some, it was running good for a car that has sat close to five years. Now it has no injector pulse, the coil is good, and the stim board is showing nothing on the little led light on the stim board. I have taken the box out of the car hooked up the stim and my laptop, I have no rpms at all on the laptop. When the problem started the car drove nice and it would just quit, I'd pull over and crank it over and it would eventually start, drive for a while, about five minutes or so then the same thing..... Now I have searched, another reason I havent logged in for forever is the search button works well, Have a problem come here search, find answer. Now I'm stumped. Here's a rundown of what my car is.... F54 block and p90 head n42 intake stock injectors 290cc 60 mm 240sx tb big fmic billet fuel rail MS version 3.0 moby's maps I know Im forgetting something, It's late, so thanks in advance guys.... Quote Link to comment Share on other sites More sharing options...
Challenger Posted September 16, 2010 Share Posted September 16, 2010 Alright you did forget a few things. haha Your throttle body, intake, intercooler and block really dont matter. Things people need to know to help you... 1) Where did you buy the MS? Preassembled? Used? 2) Have you checked for shorts or similar wiring failures? 3) Maybe a little more info on the problem and when it was happening 4) Do you have power anywhere in the injector wiring? 5) Does the engine just crank forever or every once in awhile does is sputter/try to start? I havent finished my MS install yet but I remember reading something about injector drivers possibly overheating? Might search for threads relating to that. Remember detailed information is very important with wiring help. Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted September 16, 2010 Share Posted September 16, 2010 Ok, let me make sure I'm hearing you right on what is going wrong. You are (1) not having any injector pulse width, and (2) not seeing any RPM when the engine is cranking? In that case, you will need to fix (2) first; the MS "thinks" the engine is stopped, so it's not giving it any fuel. What exactly are you doing for ignition? Quote Link to comment Share on other sites More sharing options...
Hotshift13 Posted September 16, 2010 Author Share Posted September 16, 2010 LOL, I figured I forgot a few things! To answer the questions Challenger asked: 1) MS I bought it as a kit> I started the assembly, my friend who is an electrical eng. finished the board, and it worked fine. 2)Checked over the harness for shprts and loose wires and found one ground and fixed it, but it didnt seem to "fix" it... 3)I don't know if the injector wiring has any power, I checked it with a noid light, but no blinking at all, and thefirst light on the side isnt working either. 4)I can turn the car over and nothing, it just spins over, no pops or sputters... Quote Link to comment Share on other sites More sharing options...
Hotshift13 Posted September 16, 2010 Author Share Posted September 16, 2010 And for Matts question. Your question is correct, it is doing just that. For ignition im using the stock set-up for now, the coil has spark, And now I discovered that with the coil wire disconected, The red led blinks on the MS box....Odd.... Thanks for your time guys... Quote Link to comment Share on other sites More sharing options...
Challenger Posted September 17, 2010 Share Posted September 17, 2010 (edited) Another thing to research, Matt will have to do specifics but I guess megasquirt wont start injecting fuel until a certain rpm is reached, so if the rpm signal isnt getting to MS it wont know to start firing the injectors. Edited September 17, 2010 by Challenger Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted September 17, 2010 Share Posted September 17, 2010 Another thing to research, Matt will have to do specifics but I guess megasquirt wont start injecting fuel until a certain rpm is reached, so if the rpm signal isnt getting to MS it wont know to start firing the injectors. Normally, MegaSquirt will fire one pulse when the key is first turned on, to clear air from the fuel lines. Then it shuts off the injectors and waits until it gets an RPM signal until it starts up the injectors again. It also shuts off the fuel pump after 2 seconds if it sees no RPM. Are you seeing RPM in the tuning software when you crank the engine? Quote Link to comment Share on other sites More sharing options...
jacob80 Posted September 17, 2010 Share Posted September 17, 2010 If I were you, I would definitely get my tach signal figured out first. As mentioned above, if it doesn't see any tach signal, it doesn't even know you're trying to start/run the car. Quote Link to comment Share on other sites More sharing options...
Hotshift13 Posted September 18, 2010 Author Share Posted September 18, 2010 There is no tach signal at all. I looked over my harness and I didnt find anything wrong with it at all. I made the harness very simple. Also the fuel isnt hooked up to MS, I'm still using the stock wiring for that. Thanks for the thoughts and help... Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted September 27, 2010 Share Posted September 27, 2010 Is this a '82-'83 Turbo distributor or something else? Quote Link to comment Share on other sites More sharing options...
Hotshift13 Posted October 12, 2010 Author Share Posted October 12, 2010 Found the problem, It was the MS box itself. took it to a friends house and he went thru it and found that there was a bad doide in the system. So it is up and running, but it runs like crap now.... TYhanks for the input guys!! Quote Link to comment Share on other sites More sharing options...
twogees Posted October 18, 2010 Share Posted October 18, 2010 Ok, i didnt want to start a new thread, im having the same prob..my MS 1 v2.2 used to be hooked up and ran fine. just got the car hooked back up tonight after 2 years and im getting no rpm signal or inj pulse width readings. im only using ms for fuel. im using a non turbo dist msd btm and msd coil, the btm is run of a magnetic pkup. theres power going directly to the msd from the battery but theres no spark from coil , power to coil from msd or rpm signal.IM wondering if the msd went bad from sitting so long. now from reading this i now understand that with no rpm the injectors wont fire. IM getting power coming outta the injector resistor box to the injectors, the plugs smell of 0 fuel but theres definitely plenty of pressure at the rail. im itching to get this baby fired up and help or ideas is appreciated thanks-Ben Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted October 18, 2010 Share Posted October 18, 2010 Ok, i didnt want to start a new thread, im having the same prob..my MS 1 v2.2 used to be hooked up and ran fine. just got the car hooked back up tonight after 2 years and im getting no rpm signal or inj pulse width readings. im only using ms for fuel. im using a non turbo dist msd btm and msd coil, the btm is run of a magnetic pkup. theres power going directly to the msd from the battery but theres no spark from coil , power to coil from msd or rpm signal.IM wondering if the msd went bad from sitting so long. now from reading this i now understand that with no rpm the injectors wont fire. IM getting power coming outta the injector resistor box to the injectors, the plugs smell of 0 fuel but theres definitely plenty of pressure at the rail. im itching to get this baby fired up and help or ideas is appreciated thanks-Ben Are you getting the MegaSquirt's tach signal from the MSD box's tach output? Quote Link to comment Share on other sites More sharing options...
twogees Posted October 18, 2010 Share Posted October 18, 2010 hey matt-yes i got the ms harness tach wire plugged directly into it .checked my power running from batt to msd box, switched power to the msd, then power and ground to coil. but no power to coil from msd with test light. but no rpm sig to MS either. Im not an expert or gotten real far yet but everything else seems to be reading that i can see tps, clt etc so i dont think (hope) my prob isn't anything on the MS side. where would the msd read rpm signal from. magnetic pickup? could there be a prob with that? but it should still at least get power to the coil i would think. man i hate wiring. :blink: Quote Link to comment Share on other sites More sharing options...
twogees Posted October 18, 2010 Share Posted October 18, 2010 i dont know if it matters but my fuel pump is not hooked through MS.theres no fidle wire. i dont have a stim board. only the middle led on MS comes on for a sec or two when i turn the key. when MS is open the rpm and inj plsewdth are in red. the MT version i have is 2.25b514 beta. Quote Link to comment Share on other sites More sharing options...
twogees Posted October 19, 2010 Share Posted October 19, 2010 ok tried to bypass the msd just to see if i could get spark. No go. So my guess is the dist isn't sending a signal to the msd for fire,rpm. Did a resistance check between the two wires coming from the pkup in the dist to the ic unit and was getting varied readings depending how i moved the wire. does that mean there's a short in wire? took the magnet off and it was cracked in several places. i would hate to buy another dist to set it back up like this (i want to go edis) but im on a time crunch cause im moving in the next week or so and my car has to be mobile. does that sound like the culprit to you for lack of signal? should i upgrade to a turbo dist instead of another n/a dist. im gonna try to read more about it but i dont think i can make the switch happen in time. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.