jeffer949 Posted September 14, 2008 Share Posted September 14, 2008 Ok I have been fighting a missfire/breakup for the past couple weeks. Car runs great besides this break up. It will do it while cruising and while under boost but id say its more while under boost. I Have a few datalogs of when its doing it and ill attatch them. When it happens my RPM signal goes away and either my voltage spikes to like 17-18 volts or it drops to like 3-4 volts. Ive cleaned all my grounds and my battery terminals. Also on 3 different occasians my Firmware has been erased. All my maps and settings, everytthing No damage to the ecu i just have to reflash everything. My question is do you guys think my voltage regulator is going bad and causing the problem. Or do you guys think that my CAS is going out and causing my ms to mess up or something? IDK here are the data logs. On the data log it did it on record 132,163,412,418,428,4399,4453, datalog.zip Link to comment Share on other sites More sharing options...
jeffer949 Posted September 14, 2008 Author Share Posted September 14, 2008 anybody? Link to comment Share on other sites More sharing options...
big-phil Posted September 15, 2008 Share Posted September 15, 2008 my car had the same thing happen. Left me stranded once. If I would of thought to reload the firmware I could of drove the car home. any way my car would cut out under boost, I never did notice what the voltage was doing though. The car would even cut out when I opened and closed the hood. Well what fixed the car was me cleaning the plug, and wires going to my dizzy. I think my cas signal was getting interrupted and then some how screwing up the firmware in megasquirt. I would start the car and wiggle the wires coming out of the dizzy, then follow them to your relay board or megsquirt. I did the same thing, changed power and neg. wires. I hope this fixes your problem. Link to comment Share on other sites More sharing options...
Zmanco Posted September 15, 2008 Share Posted September 15, 2008 I think you should focus on what's causing the noise on your battery line into the MS. The CAS signal may have its own issues, but I don't think that would cause the noise on battery voltage and doubt it would cause the flash data in the CPU to be erased, at least not all by itself. I had an issue with random resets and in the end traced it to EMI from the spark plug wires. I switched to Magnecor wires (#6524) and that solved it. (Magnecor claims to have the best EMI suppression.) I only mention this because when dealing with noise, the sources aren't always obvious. I'd suggest turning everything that is not essential off for a while and see if the problem persists. BTW, how is the wiring to your fuel pump? A big pump can have a large inductive load and might cause this kind of noise if a connection was loose/intermittent. I suppose it could also be the regulator, but unless you are seeing other signs that point to it, I'd look elsewhere first. Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted September 15, 2008 Administrators Share Posted September 15, 2008 Gut instinct says "MS resets". (MS Resets is where the ECU literally shuts off for split second and turns back on, very quickly, engine has very harsh stumble each time, and can be multiple resets, one after another, or random hit and miss resets.) MS is very sensitive to EMF interference, especially from mediocre spark plug wires, non resistor sparkplugs, noisy alternators, etc. etc. Here is a great thread covering MS reset issues and techniques employed to reduce the chances of these nasty very annoying resets. http://forums.hybridz.org/showthread.php?t=112407 Link to comment Share on other sites More sharing options...
jeffer949 Posted September 15, 2008 Author Share Posted September 15, 2008 My car doesnt have anything that isnt essential. Radio doesnt work and no ac and no aftermarket lights. My fuel pump wiring is a wire from the relay board directly to the pump and then a wire to ground. But my fuel pump is in the engine bay next to the alternator. My car is in nashville right now and im in Florida so i wont be able to work on it till wed. or so. Keep the ideas coming. As i really dont have money to start throwing parts at her right now. Link to comment Share on other sites More sharing options...
Matt Cramer Posted September 15, 2008 Share Posted September 15, 2008 It's definitely resets and they show up as such in the data log. First thing I would try is putting a stereo noise filter on the 12 volt supply line. Link to comment Share on other sites More sharing options...
Careless Posted September 15, 2008 Share Posted September 15, 2008 But my fuel pump is in the engine bay next to the alternator. full, unobstructed fuel flow and an open-housing electrical generator. sound like a good idea to you? is someone with me on this or am I just worrying too much. especially after all the work you just put into getting it lookin all purdy like Link to comment Share on other sites More sharing options...
jeffer949 Posted September 15, 2008 Author Share Posted September 15, 2008 The mechanical fuel pumps that came stock on our cars when they where carbed was directly over the alternator...... Link to comment Share on other sites More sharing options...
z-ya Posted September 15, 2008 Share Posted September 15, 2008 Looking at the datalog, it could be either resets, or a bad +12V connection somewhere. You need to monitor 12V at the MS when this happens. You can do it with a test light that you can see while driving (or an analog volt meter if you have one). Link to comment Share on other sites More sharing options...
jeffer949 Posted September 16, 2008 Author Share Posted September 16, 2008 I know my Power wires are good. They are soldered in place. Ill try the noise filters on the constant power wire and the switched power wire. Do i get those at radio shack? Also I have NGK plug wires and i have B8ES plugs in the car i believe. Ill try to get some BR8ES plugs also. and see if that helps. Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted September 16, 2008 Administrators Share Posted September 16, 2008 ..... Also I have NGK plug wires and i have B8ES plugs in the car i believe. Ill try to get some BR8ES plugs also. and see if that helps. Non resistor spark plugs is one of ANY after-market EMS worst enemies. For MS, no resistor plugs is reset city!!! You'll also want to get plug wires that plays well with after-market EFI such as Nology or Magnecor. Let us know how the new plugs work... Link to comment Share on other sites More sharing options...
Matt Cramer Posted September 16, 2008 Share Posted September 16, 2008 BRAAP is right on the money with the plugs - fix that first. You don't want non-resistor plugs with a MS - or any other EFI, for that matter. I picked up my stereo noise filter at AutoZone (or maybe it was Advance - one of the cheap parts stores that starts with an A) in the cheap car stereo installation parts section. Link to comment Share on other sites More sharing options...
wigenOut-S30 Posted September 17, 2008 Share Posted September 17, 2008 I am Running Magnecor wires and have never had a problem with them.. I second that suggestion! Link to comment Share on other sites More sharing options...
jeffer949 Posted September 18, 2008 Author Share Posted September 18, 2008 Well I'm back in Nashville where the little "tempermental bitch" has been awaiting my return from the 1600 mile trip in the ultra cush minivan. So I'll be trying to get some new plugs tomorrow for her. What plugs do you guys recomend for my setup running from 15psi to 20psi. Is a 8 to cold for a daily driver? Also where do you get the magnecor wires? and do they make a kit for the L6? Link to comment Share on other sites More sharing options...
Zmanco Posted September 18, 2008 Share Posted September 18, 2008 The part number I listed for the Magencor wires in my first post worked great on my NA - I don't see why they wouldn't fit a turbo application. I bought them online as there was a wide range of prices. Sorry, can't help you with plugs for a turbo... Link to comment Share on other sites More sharing options...
wigenOut-S30 Posted September 18, 2008 Share Posted September 18, 2008 Jeff, you can get the plugs from here http://www.magnecor.com/ I had them make a custom length so I could wrap them around infront of the valvecover. They work great! Link to comment Share on other sites More sharing options...
jeffer949 Posted September 19, 2008 Author Share Posted September 19, 2008 Well i changed my plugs today and it didnt help really. Turns out i DID have BPR8ES's in there. But i got a set of BR8ES from the parts store cause thats all they had in the 8 range. Are the noise filters The inline filters or are they the clamp on filters that you see on computer cables alot? cause i saw some inline ones at advancedauto that where 10 bucks but im not sure if those are what your talking about. Link to comment Share on other sites More sharing options...
Zmanco Posted September 19, 2008 Share Posted September 19, 2008 The only noise filters I've ever seen at auto parts stores are in-line. They usually come in a few sizes based on the max current they can support. If you're switching the fuel pump off the same feed make sure you buy one that can support the combined load. I'll be curious to see if an inline solves your issue. I hope it does, but I'm doubtful. It's usually much better to eliminate a source of noise than to try to filter it out. Also, the other wires in the engine bay that connect to MS (sensors, CAS ,etc) are also susceptible to EMI. Filtering the power supply may help, but it may not be enough. Again, I'll be curious to see if it solves your problem, or if in the end you have to go with the Magnecor plug wires. My guess is it will be plug wires... Link to comment Share on other sites More sharing options...
ktm Posted September 19, 2008 Share Posted September 19, 2008 I am at 22 psi and use 7s. Magnecor plug wires are great (I am running a set as well)m but they are a little pricey. I paid $80 for mine, and they are only 6 inches long, tip to tip. Link to comment Share on other sites More sharing options...
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