MSefi.com read only forum (Jan.15,2018)

A few weeks back I finally finished the real intake I planned on using for my fuel injection project. So I took the ugly 7.4L vortec truck manifold off and on went my Mercruiser manifold that I made individual throttle bodies for each stack. I had previously had this intake on the car back in 2009 but had issues with the throttle blades not closing properly and to much air getting in causing it to idle at 1500 rpms. So now that I have reshaped the throttle bodies and had new parts machined I decided to put it back on.

So I took off an intake and the engine was running great. I put on the new intake and after a while of messing with the tune I finally got a good idle, but when I rev it up it starts popping out the exhaust on the passengers side. Mess with the fuel and timing and I can drive it down the road but its still popping out the passenger side every time I lift or push on the throttle from fully closed. Thinking it was just in the tuning I kept messing with the fuel and air. The odd thing about all of it was that the passenger side has the Wide Band and its reading 50:1 according to innovatives software. Ok so I must need more fuel at idle...nope, more fuel causes an rpm rise and the passenger side is still at 50:1. Hummm....check the header tubes with temp gun...passenger side is cold, driverside is hot. Not good. Mind you I'm using the same injectors from the last intake and all was functional just a week before I swapped the intakes.

So I flipped the injectors from one bank to the other. Still the passenger side is dead. And yes it is getting spark too. Ok maybe the MSII is freaked out, reloaded the firmware and same thing. Ok flip the wires for the banks to get the opposite injector driver to fire the opposite side of the engine. Nope still the drivers side is running and not he passenger side.

I reworked the fuel rail. Previously I had the inlet feed from the center of the passenger side. Then there was a crossover to the drivers side. Now it goes in the rear of the passenger side, loops around from the front to the drivers side and out the rear of the drivers side. Now it pops out of the passenger side like it wants to fire on all eight but not really.

Now when I rev it up or try to drive it the whole engine wakes up as long as I am accelerating but as soon as I start cruising it's like I have one of those cylinder on demand cars.

I've moved flipped switched modified everything I can think of, I'm just looking for some more suggestions of what to try....

Here's a few pictures of the project.

https://plus.google.com/photos/11594488 ... 7196099809

You've not said if there is drive to the affected injectors. For this, the easiest way is a noid light or LED and resistor. It should flash at low speeds. Or a DVM that reads dwell or duty cycle. There is also an injection test function on TunerStudio. First check you have 12v to one side of the injector at all times the engine is running.

Sorry yes the injectors click when I hold stethoscope to them. But I flipped the driver wires and still only the drivers side fired up.

I swapped the computers today, same results, drivers side fires up but the passenger side is not as dead. The O2 sensor will blip a bit at idle and if i'm driving and I'm above 8% tps the 02 sensor starts reading solid until I let up and go to 0%.