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Way way too much fuel! help

Posted: Tue Jan 19, 2010 3:03 pm
by Turboacr
Ok this is my first time posting on here . I have a 98 dodge neon that is turbocharged. i am running a symtech labs built msII v3.0 . I am running it full standalone. When i first received the unit and wired it up the vehicle wouldnt start and I sent the unit back to which they found a faulty solder joint for one of the coil drivers. Once I received it back I put someone elses map on there set my req. fuel and it started it and ran fine. I drove the vehicle a bit around town and it was running fairly well. As I was driving the car stalled so I pulled over tried to restart and it would not. I found that the inline fuse going into my megasquirt as well as my injectors had blown (small 2amp). I replaced the fuse with a 5 amp I had in the car and it was driving fine again. This happened again after driving for quite a bit more. The only other fuse I had in the car to get it home was a 10amp so i popped it in as I only had a mile to get the car home rather than pay for towing. I was less than a block away and the car stalled. I went and checked no fuses blown. when I was cranking it just smelled like fuel badly and very light amount of smoke was coming out of the exhaust (likely due to the heat from the cat and unburned fuel enteringit). I pushed it home and started to check over everything again. I found that the inline fuses that i had going directly into my injectors (2 5 amp fuses just before the injectors) were kinda loose in there holders. The inline fuse holders I had put in were mostly held together with the outer rubber housing and it was allowing the terminals to pull too far away from each other which I think was shorting and causing that 2 amp fuse to blow. So that being said I wired in two different inline fuse holders going to my injectors. I attempted to restart the vehicle after that and it was just dumping tons and tons of fuel. It actually filled all my cylinders, most of my intake manifold, my entire catch can, and most of my vacuum lines. I figured maybe my injectors were just staying wide open but I put a node light inline with where an injector would have been and I can see it pulsing on and off so i know that its not sticking on atleast on that particular cylinder. I contacted symtech who though I may have corrupted the firmware. So i reflashed the firmware and tried again. I used a completely different lap top and put a new map on. The car will start only if i have my foot on the gas and when it start its misfiring very very badly, there is actually so much fuel that it is coming out of the exhaust. I tried dropping my req. fuel in half and even cutting priming and cranking pulse widths in half. In addition I replaced the spark plugs figuring they may have been fouled. Still it was just flooding out. I did however notice that the plugs removed from cylinders 3 and 4 were soaked and the plugs from cylinders 1 and 2 were black and sooty. I checked and all 4 cylinders are receiving spark when cranking. At this point I am extremely confused. I dont know if maybe i damaged the megasquirt or if i am just doing something stupid. Any input at all would be very helpful. I also apolagize if I have left anything out. I have done all the basic testing that I could think of. Thanks in advance.
Steve J.

Re: Way way too much fuel! help

Posted: Wed Jan 20, 2010 5:47 am
by Matt Cramer
I don't know how Symtech's plug and play setups are built, but could this one be tested on a Stimulator?

Re: Way way too much fuel! help

Posted: Wed Jan 20, 2010 8:18 am
by Turboacr
I am certain it could be tested on a stimulator, but i do not have one because i purchased the unit assembled.

Re: Way way too much fuel! help

Posted: Wed Jan 20, 2010 9:55 am
by Matt Cramer
Right now about the only option would be to reload the firmware and reload the base map (I presume the unit would have come with a Neon base map?). Unless you have an oscilloscope?

Re: Way way too much fuel! help

Posted: Wed Jan 20, 2010 6:42 pm
by Turboacr
Well I have reloaded the firmware. As far as a base map although none came on the unit. There is a database of 4g63 based engines which I have tried a few different maps from. I may be able to borrow an oscilloscope from a buddy. What test would I be able to do with that? After thinking about this more today I wonder if it is possible that I have one or two injectors that are sticking open. Although these injectors were new before going megasquirt i guess with the problems I have been having I could have damaged them. I guess I could lift the rail up, put a large tray down, and either flip the key on and watch them prime or better yet maybe let it crank for a short period of time and watch the injectors to see. Thanks for the input thus far I very much apprectiate it.
Steve