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Re: [GMCnet] FITECH Mystery solved [message #328477 is a reply to message #328471] Sun, 21 January 2018 21:01 Go to previous messageGo to previous message
Larry is currently offline  Larry   United States
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Registered: January 2004
Location: Menomonie, WI
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glwgmc wrote on Sun, 21 January 2018 18:51
Some of you will remember that the new owners of our Clasco experienced a no start issue following refueling south of Denver last summer on their way back to Alaska. They reverted to the carb and made the rest of the trip. At the time there was much speculation on this forum as to the root cause issue. Many speculated that it might have been too much heat for the throttle body mounted ECM, others that the high pressure fuel,pump inside the fuel command center might be bad, etc.

We are in Quartzite, AZ for the day and it turns out the new owners are as well and found us. It turns out the issue was an intermittent failure of a connection inside the main factory wire harness plug. He said he called the factory when they got back to AK and asked the FITECH guys what the problem might be with the throttle body. They had him reinstall the FITECH throttle body and it fired right up so the mystery remained. Later he said they experienced another failure after fueling. That time he rooted around under the hood and while moving things around heard a click. The FITECH fired right up again. He then could replicate the issue by squeezing that connector, one wire crimp was faulty inside the plug. No issues since.

Who would ever have thought a factory crimp could fail intermittently inside a factory plug.........

Jerry Work




With my FiTech, I have high pressure pumps in the tanks feeding a pressure regulator and dead heading to the Fitech. I was having trouble with no start after a hot run stopping for fuel. Hooked up a fuel pressure gauge and found that on shut off, the pressure burried the needle on the gauge. If I released the pressure, I got immediate start. I'm speculating that the pressure got so high that it held the injectors closed for a no start. Releasing the pressure allows for the pump to pressurize at normal 58lbs and allows a normal start. Currently thinking about adding another Fuel pressure regulator at the output side of the FiTech to bleed pressure in excess of 70lbs or so, back to the fuel filler pipe. I did this when I had the same trouble with my EBL system. Eliminated the no start issue. Just what I think.



Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
 
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