Atomic EFI Update

It has been my experience that all non-laptop self learning systems have issues with low vacuum engines. The ECUs look at vacuum to determine engine load and when the vacuum is jumping around 3 to 5 inches because of cam durations and low LSAs there's just not much you can do. All non-laptop systems need an idle vacuum of at least 8 inches. Laptop systems can handle this because you can manually do whatever the engine needs.

As far as failure rates - you have to admit that all electronics is pretty good. Barring any customer induced problem, it's not the electronics that fail, it's the mechanical parts. Number 1 failure is the fuel pump. And that's usually because they are installed poorly. Hot fuel can cause cavitation and any electric pump will fail if it's inlet flow is restricted.

Injectors almost never fail unless you get dirt in the system. Then they clog quickly, but that should never happen in a correct installation.

Next is mechanical relays. Sure they're cheap and easy to replace, but they are still mechanical. There are very few relays in a carburated engine. Lose a relay in an EFI engine and it dies.

Next is crank and cam sensors. Separate inductive or hall-Effect sensors (like a crank trigger) are great, but those distributors with multiple sensors are complicated and tend to be a failure mode. That's why all my cars use separate cam and crank sensors and no distributor at all.

Next is TPS and IAC sensors. Their failure rate is very low, well below the distributor level, but they still wear out.

Temp sensors never fail.

Do a good clean installation, pay attention to the instructions, and don't scrimp on the fuel system (good pump, filters and fuel line routing) and these things will run as long as any new car.

I'm very finicky about failures and I don't like distributors so all my cars are coil-on-plug. Now there is nothing left to fail expect the fuel pump which I'm sure it will.

The EZ-efi from FAST is a good system, but Rich is correct about the low vacuum sensativity. If your not pulling at least 10" on vacuum at idle, it will not hit the target A/F until it get what it considers full vacuum...I have fought with this issue myself, and sometimes miss what you can do with a fully progamable open system. My solution was a custom curved distributer that has more timing at idle than a factory one.

The other issue with the Mopars seems to be cold starts. I have also had this issue when you first fire it up and it dies unless you have your foot on it...When I talked with Rich, he had a neat idea. Run the fuel pressure higher than 43lbs, but leave the computer thinking it was still at 43lbs. In essence your giving the motor a bigger start up shot of fuel until the computer see's the O2 reading.

I have done this, and it works pretty well, unless you hit the gas hard while its still cold, you can actually flood the engine for an instant and stall it...The other extreme.

And as stated, follow the instructions!

The other issue is more of an annouyence really during start-up, you have to push a few buttons to have the read out actually show anything other than "Comm Error"....It should just boot to the main live screen.

Pretty much all new cars are returnless now, it is done for emmisions control and MPG. The fuel in the tank won't get heated and evaporate nearly as fast. This will also make the fuel last longer (time wise) as all the lighter molecules stay in the tank longer instead of leaving the mix and leaving heavy long chain hard to burn molecules. You will also get better mpg because the fuel is now hotter when injected so it evaporates in the intake and obviously since your fuel in your tank is not evaporateing you get more of it into the engine over the course of useing the tank.

Now for drag raceing it (a return system)could be usefull to build a couple more HP, especially with a throttle body injection. The fuel will be continually cooling the throttle body (while running) and that will cool the air/fuel mix in the manifold and allow more molecules to be packed into the cylinder and could also help with detonation if you are running borderline fuel octane for your engine.