JacksonM

Hey guys I've been dealing with my fc not starting since around early march and I've pretty much ran out of ideas, so i thought I would ask someone smarter than me for help. It all started when I had the car running good and then it just died on me out of nowhere on my way home from school, we tried jumping it and even putting my friends battery in but it was a no go so I got it towed home. The next day I went to check on it and it started right up, but I stalled it like an idiot going down my street and then it wouldn't start again and hasn't since. At first I thought it had been a clogged fuel filter because there was pretty old gas in the car and the fuel filter was pretty old so I replaced that but still nothing. I also cleaned the injectors and the throttle body to no avail. I asked around and was told It could be because of an internal leak in the fuel pump so I replaced that on a whim but still nothing. So at this point I pulled the plugs like I should've done in the first place and saw they were covered in gas so I ordered new plugs and did the standard deflooding procedure, threw the new plugs in and still nothing. So today I tried the trick in the FAQ where you put a little oil in the spark plug holes and crank it with the old plugs to help build compression because I read that when the motor floods it loses compression. Did that threw the new plugs back in and still absolutely nothing. I've run out of ideas but all I know is that I have spark, I spark tested everything yesterday, and I have fuel (had injectors out of the block and watched them spray). The car has a fueltech ft450 ECU on it that we had tuned just enough to start the car by a fueltech employee over the phone. The motor only has 600 miles on it but it was rebuilt by the PO so i'm not sure about how good of a job he did but I'm just hoping somebody has an idea. Sorry for the long post but I've read a million forums and tried everything I've seen so far. Thanks to anyone who can help.

diabolical1

iTrader: (3)

welcome to the board, Jackson.
if i had to bet, it would be that your problem is going to lead you here ... to the new ECU. do you have any control over this ECU or is this one of those things that someone does remotely?

you've already seemed to confirm spark and fuel. my advice would be to disable the fuel pump and try to see if it will fire on starting fluid. if it does, then you're going to have to learn (or find someone) to mess around with the tuning on your FuelTech. probably removing fuel from the startup map, and then take it from there.

JacksonM

I am able to mess with the tune on the ECU so that might be a good start, however i just tried using starter fluid with the fuel pump disconnected yesterday actually and there was nothing. it is possible i didn't unflood it properly but I was pretty thorough.

Dak

I just wanted to chime in here. I have a FT550 but unfortunately, I haven't installed it yet(only got so far as creating my base map) so I may be of no help to the O.P. I did want to say the Fueltech ECU's are fully programable by the user.

To the O.P. are you tuning the ECU with a laptop? If worse comes to worse you can save that tune you have and start over by creating a new base map. I would almost say to give this a try. The software on the laptop combined with the manual walks you through the creation of the base map pretty well. It will also give you a pin out of the harness when you finish the base map, which may be useful to confirm everything is wired up right. You can always reload your existing tune if creating a new base map doesn't work out.

JacksonM

I have a laptop I can use so I could do that I know somebody whos half decent at tuning so I might give him a call

Dak

You can get the Fueltech software for your laptop here: Software - FuelTech USA
And the manual here: English Manuals - FuelTech USA

JacksonM

I've been super busy but I finally got around to looking at my tune and it looks like the injector prime pulse is way too high at least from my limited tuning knowledge. I read somewhere that it is supposed to be between like 2 and 4 milliseconds and mine is at 95 so i think there may be an issue there.

JacksonM

j9fd3s

iTrader: (3)

ive noticed that best starting performance happens right before the engine floods. it can take a couple tries to get it right, it varies with each engine/car/setup.
ideally what you want is to have the warm idle set where the engine is happiest (most vacuum, usually)
then you'd play with the cold start enrichment (i took a note of the warm idle AFR, and the AFR when it started cold, and then just sat there and adjusted the map so it stayed consistent the whole time)
then you can adjust the cranking map. its kind of a PITA, but you make a change, start the car, run it enough to verify stuff, shut it off, let it cool, and try again. its like a lazy Sunday thing

usually the ECU takes the rpm and fuel setting in the idle cell, and then it adds the temperature enrichment, and then it adds the cranking fuel, so cranking is a mix of all three.

JacksonM

So youre saying i should look at the idle maps first before messing with the cranking stuff?

j9fd3s

iTrader: (3)

ideally, although if you need it to start, you need it to start

the idle, warm up enrichment and the cranking fuel are all related

JacksonM

So I called fueltech tech support today because I've had good luck with them in the past, and the guy was very nice but after 2 hours of us testing fuel, spark, timing, etc. he ran out of ideas. So he gave me a tune that if the car was working properly it should run and told me to see if I could find any mechanical issues with the car or possibly a clogged intake manifold. So I am going to start checking things over now. Any input is appreciated but at least now I can rule out the tune as an issue.