Speed-Pro install (no start)

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502SS

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I have installed my Speed-Pro and a MSD Dist.
Connected to PC and all sensors read great. Cranked it over and it fired once, so I shut it off right away to set up my timing light.
Got it set up and now I can't get the truck to start. Cranks and cranks but no fire. Pulled coil wire and got spark.
It smells flooded but I can't tell now.
Any thoughts????

John
 
If you put a timing light on and you still have spark, the obvious thing to check is fuel. I seem to recall that the FAST has a "clear flood" mode - put the accelerator to the floor during cranking, it won't fire the injectors.

Also, watch your RPMs on the dashboard - if you're indicating like 100 RPM's or more, then you should be okay. I had a weird problem where the ECU thought I was up around 11,000 RPM during cranking- if you see that, email me off-list and I'll tell you what's happening.

Watch other things on the dashboard as well- injector pulse width (or duty cycle), timing degrees, etc., are good for a reality check.

Then there's the bonehead move I made once- forgot to plug in the fuel pump relay. That will also give you a hard time starting. A good way to check to make sure your pump is running is to change your FP prime time to like 20 seconds, turn the key forward, and listen for the pump to be running and fuel to be dribbling back into the tank.

-Bob Cunningham
bobc@gnttype.org
 
John, I recently had a similar problem firing up my LT1 with a new Accel DFI (not a Gen7). I ended up using starting fluid to get it running long enough to realize that my fuel pressure was way too high and causing the injectors not to fire. I had installed a new adjustable regulator along with the new fuel system and I just guessed on the pressure. I adjusted it down while feeding it starting fluid and it started running on its own!

Butch
 
John, I just re read your post and saw that you said it smells flooded. In my case I didn't smell any fuel. But, the starting fluid might help to keep it running long enough to troubleshoot. The suggestion to open the butterfly's makes some sense also, to me anyway:D

Butch
 
I still have spark and my fuel pressure is steady at 55lbs.
I cranked it a few times with throttle wide open (flood clear) it coughed once and backfired out the exhaust but real muffled.
My injector pulse at cranking has been from 25 to 35ms.
The IAC is around 200, all this is at 70 degrees.
My battery is now on the charger, I tried that long!
There has got to be something I'm overlooking.

John
 
My injector pulse at cranking is around 13ms. Backfire sounds like timing issue. Have you double checked that? I think there is some trick to setting the initial timing with the SpeedPro, I am no expert! You can do a search.

Something elso comes to mind... At first I thought my fuel pressure was OK but then I realized that it changed drastically once the engine was running!

I am just thinking out loud here:D

Butch
 
It's to late tonight.
I'm going to lower my injector pulse width way down tomorrow morning. If that doesn't help then I will pull my distributor and hopefully it is setup wrong. I can't think of anything else. It has to be fuel or my spark is at the wrong place.

John
 
I wouldn't be able to sleep:mad:

My guess is spark in the wrong place FWIW!

Again, I am NO EXPERT!

Butch
 
I put the dist. in and set the #1 wire at the rotor with the crank at btdc, when I crank it I see 6 or 8 degrees before the 0 line.
Maybe I missed the compression stroke on #1 when I put in the dist. My timing light would not see a signal through my MSD 8.5 wires so I put a stock wire on #1 and got my timing that way.
I think I'll get a new light tomorrow just to be safe. Can't figure out why it won't read though the 8.5 wires.

John
 
Like I mentioned before, there is something with the Felpro and 6 degrees difference. I don't know the details. Lance can tell you, maybe he will chime in tomorrow.

Butch
 
Thanks for your input, I thought about it more last night and decided my ignition had to be fine (to many redundant checks).
When I replaced my factory injectors with the 30lb. ones I had not finished wiring my Speed-Pro and I drove the truck for about an hour. It was way!!!!! rich on the factory ECU. Later that day I finished my wiring and dist. install with no starting. This morning I pulled one plug and wow - black and wet. Changed plugs with some old ones and one crank later it was running!
Now for fun tuning, this thing looks to be great.

John
 
So did you turn down your cranking pulse width? How did you fix it?

Butch
 
Originally posted by Butch
Like I mentioned before, there is something with the Felpro and 6 degrees difference. I don't know the details. Lance can tell you, maybe he will chime in tomorrow.

Butch

Butch,

You are thinking of the Accel DFI system. That system uses a fixed crank reference angle of six degrees, so any ignition system (such as a Buick DIS) that does not use a six degree reference angle will (I believe) reflect an error between the spark table and the timing light equal to the difference of the actual reference angle vs. the built-in 6 degree reference. Since the FAST reference angle is adjustable, you should ALWAYS see on the light what the computer is telling you it is putting out. If not, the reference angle should be adjusted until this is the case.

Craig
 
I lowered the cranking pulse way down and also the starting IAC position down also. I think it was a combo of way fouled plugs, low battery, and way to much gas. It starts great but still needs tweaking at idle. I can't run it to hard right now because I still have the Paxton FMU regulator, my fuel pressure runs to well over 100 psi at 5 lbs. boost. That was one of my reasons for piggybacking a Speed-Pro unit on top of my stock OBD-II ECM. Well 502 blown cubic inches was another good reason I guess. Any guesses on how 6000 lbs. of family hauler will be on the way to Grandma's house now?

I appreciate the fast responses and I'm sure I'll have plenty of questions in the near future.

John
 
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