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So I recently finished my Fitech install, and everything was great. Truck started every time no problem, ran great, and I had even taken it up and down my road a few times to try it out (not road worthy yet so driving is limited). One time it stalled on me, but I assumed I ran out of gas. Threw in another 5gal jerry can and off to the races again. About a week ago I was playing around, had to move it out of the shop to work on my dad's brakes, and when I went to put it back, it started great as usual, so I went for a quick spin (like 1/4 mile) and it died right in front of my house. It seemed like it was a fuel issue again, so I went to town to get more gas but it didn't help. I had to push it back into the shop, as no matter what I tried, it would crank and not fire.

I've left it for a week or so, knowing I was too mad to get into it. Today I decided to take the battery off of the charger and put it back in to see what would happen. Once again nothing. The truck will crank forever but will not start. There's tons of gas, and it has been running great and starting without issue since the install. The fuel pump is definitely running, so I have no idea why all of a sudden it won't start. Only thing I can think is that something in the ignition, unrelated to the Fitech install may have crapped out. Anybody else had a similar issue?

Kind of bummed as mechanically the truck was thought to be ready to go, I was prepping myself to tackle body work for the first time and now this. Any help would be appreciated.

The fuel pump is definitely running

But did you make sure fuel was being pushed to the Fietch unit?

Is your fuel pump in line? Do you have a fuel pressure gauge? I went thru 3 in line pumps with my fitech. I'm in the process of installing new tank with in tank pump now

First two things to always check. Fuel, and spark. One of the two isn't there.

On EFI could be any number of things.
It may have fuel & spark, but still not start.

You'll have to do some troubleshooting. Start with basics. Voltage checks, FP check, spark, etc.
If you take gander @ handheld does it show values for all sensors etc. w/ key on engine off?

The handheld,shows,fuel,pressure,coming in.

When I installed mine my fuel filter plugged up. But I had been working on gas tank before so a lot of fashizzle came through from the tank.

That's what I was wondering about. I have a Walbro pump mounted in the tank, and inline 30 micron filter. Not sure if I have pressure, no gauge but going to install one for sure. Time to start troubleshooting I guess.

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Does your system have a "Clear Flood" mode? Have you tried holding the pedal to the floor while cranking? I know, unlikely to still be flooded after several days, but who knows....

Check your ignition. Looks like it takes the signal from the factory or aftermarket ignition. If using a stock distributor, loosen it and wiggle it back and forth and VERIFY that you are getting spark.

As mentioned, you need fuel, air and spark. You probably have air. You need to check and VERIFY the other two.

Have a helper crank while you verify fuel being sprayed into the throttle body bores.

So just checked the fuel filter I mentioned above and it's clean as a whistle. When I had the work done for adding the pump to the stock tank, they cleaned the tank as well, so I assumed that wouldn't be the issue. I did find one of the wire on the coil (one I tapped into for the Fitech) was a little loose on the coil, but I pinched it tighter and it still won't fire.

I scanned through the dashboard on the Fitech handheld while cranking and everything seems fine, the fuel pump is going to 100% duty cycle, its creating vacuum, etc, however the one thing that I am not sure about is the Fuel Injector Duty Cycle %. This reads 0 no matter what. I would think that this should be reading something other than zero to allow the injectors to actually spray. I'll have my wife crank it over tonight and I'll look down inside to see if its spraying fuel, but if the handheld reading means what I think it does, maybe the injectors are stuck or not being told to open? Anybody have a better idea of what that reading on the handheld means?

Not sure about injectors but the fuel pump 100% duty cycle is just telling you the fitech is send a message 100% of voltage to pump.......doesn't mean pump is pumping..........

You could go Old School and put a bit of fuel into the throttle body and see if the engine runs briefly.
A timing light or spark plug grounded to the exhaust manifold will tell you a lot as well.

An old rule of thumb: Just because it is new does not mean it hasn't failed®

I realize you have a different system but bad grounds caused me a lot of grief with my TBI after several years of solid and dependable use.

what is your rpm reading in the handheld when you crank it?

nightglide wrote:what is your rpm reading in the handheld when you crank it?

160 ish. I phoned Fitech yesterday and they walked me through a number of checks. No fuel squirting into TB that I could see when cranking. I ordered an inline FP gauge so I'll throw the on this week and see what's going on. Maybe I fried the pump the first time I ran it dry? It's a Walbro GS342 btw.

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PUDS wrote:

nightglide wrote:what is your rpm reading in the handheld when you crank it?

160 ish. I phoned Fitech yesterday and they walked me through a number of checks. No fuel squirting into TB that I could see when cranking. I ordered an inline FP gauge so I'll throw the on this week and see what's going on. Maybe I fried the pump the first time I ran it dry? It's a Walbro GS342 btw.

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Can't you crack the fuel line before it reaches the FI and turn the key to verify the pump is moving fuel??


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Yes but don't feel like spraying fuel all over the engine bay. Plus, it'll be hard to tell the difference between 20psi and 60psi I'd think. TB needs thr 58psi or better.

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PUDS wrote:Yes but don't feel like spraying fuel all over the engine bay. Plus, it'll be hard to tell the difference between 20psi and 60psi I'd think. TB needs thr 58psi or better.

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Removing the fuel line and checking flow it won't build any pressure or very little. Without a regulator it's simply a flow check.

14-15 psi outside of the injection unit.

az chip wrote:14-15 psi outside of the injection unit.

Which could easily be aimed into a container instead of sprayed all over.


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Make sure it's a red milk jug