Fuel injection variations / possibilites for dummies?
 

G'day Folks,

I'm looking for an easy way out - I'd like to know more but in a BS free concise way!

Megasquirt?

CIS-E?

Jetronic?

WTF?

It is a popular all the rage subject with promises of Nintendo onscreen compatibility - improvements in fuel economy - improvements in performance - and improvements in fashion and street cred...

...seems to be a mine field of "do this" "do that" "spend at least a grand on this and that"...


Errrrrrr - help!


Reasonable information seems to be here =>

280SL "K-Jet and Ignition conversion to Megasquirt" write up - Benzworld.org - Mercedes-Benz Discussion Forum

280E: Converting K-Jetronic to EFI (22/09/2013) PHOTOS - Benzworld.org - Mercedes-Benz Discussion Forum

Jetronic - Wikipedia, the free encyclopedia

Can someone give me a simple break down of advice for this old school mechanical doesn't understand electrickery diesel dummie?

It all depends on what you are trying to achieve and on which system.

There are a number of aftermarket systems with a plethora of fuel/spark control combinations.

Original stock Bosch systems are usually K-jet or CIS-E.

These are both basic systems which are manually adjusted. The amount of fuel injected is determined by how much air is being passed through the intake. Most of these systems work off a predetermined fuel curve with little or no adjustment possible. You set the initial base amount of fuel and the rest is operated by the movement of the air flap. Cold starts, idle air controls, etc., are handled though separate solenoids or valves using a variety of sensors. No spark control. Basic , crude but very simple.

Drawback is since you are working on a predetermined fuel rate if one component in the system is wrong then they are all wrong. If the WUR (warm up regulator) malfunctions and adds additional fuel then the system still allows the calculated amount of fuel to the engine according to the air flap resulting in a rich running condition. Vacuum leaks create a "lean" condition, etc.

Aftermarket and newer injection systems use controlled injection. The amount of fuel is controlled by sensors and adjust themselves "on the fly" according to the input they receive. Much more efficient, infinitely adjustable and is usually tied into the ignition system for maximum output. Most of these systems can be "re-programmed" or adjusted by either a remote computer input or controller chip replacement. MUCH easier to diagnose and correct problems using the proper scanner.

Drawbacks, more "wizards" required to work together. Can be sensitive to electrical malfunctions and surges.

Well I guess I'm interested in something that can be tuned via a laptop. I'd like to be able to adjust fuel and spark as a play thing and I'd like to be able to record and store data for future messing about.

Eventually I'd like to be able to program in my own routines that would enable best guesses for situations where certain sensors might not work as they should - a kind of electronic brain redundancy for sensors...

...however, has to be done on a diesel owner's budget!

Fuel injection - Wikipedia, the free encyclopedia

http://auto.howstuffworks.com/fuel-injection.htm

Megasquirt would be the way to go.

About $250 for the electronics.
And you will have to fabricate the fuel rail, a crank position ring, maybe install an O2 bung on your exhaust. Then you have to source some injectors, the O2, and other bits I'm sure.

Contact E30M42 on this forum. He is looking into doing this to his 1985 190e. Looks like a lot of work to get it right. But the rewards would be great.
More power, better economy.

MegaManual Index

I believe Graham installed the MS using his stock fueling set-up so no extra fuel rails etc. would be required.

I converted my K-jet to MS but I had to make up the fuel system in order to use the Bosch electronic injectors. About $800 USD in parts costs but my fuel distributor was completely knackered. I was looking at a minimum of $1200 USD for an "iffy" rebuilt unit plus whatever else I would find wrong. Made more economic sense for me to upgrade the entire system on my M117.

Note if you modify a vehicle system to non-factory, then all of a sudden all those Mercedes repair shops out there no longer have documentation, test equipment, test procedures, or the troubleshooting knowledge to fix your modified vehicle!

So if something stops working, you will be on your own to troubleshoot and fix it. Best you totally understand these systems so you can do that.

If you just want to tinker with the adjustments on a fuel injection system for any vehicle - does not matter if Mercedes or not, then might want to poke around the following site which has free "tuning" software for certain 90's vehicles (and buy one of those vehicles to experiment with).

With that you would modify the programming on the vehicle's computer chip and plug it into the vehicle's computer. If your modified programming did not work, you could re-install the factory chip. Or if you need to take it to a mechanic for troubleshooting, you could reinstall the factory chip.

Tuning software...
TunerPro and TunerPro RT - Professional Automobile Tuning Software

Interesting 90's GM free vehicle computer reading software...
WinALDL - 160 baud ALDL reader

Hmmm, I'm thinking our man Stretch isn't too concerned with Mercedes shop technicians.:D

Megasquirt is definitely the way to go. It will be a steep learning curve if you are not already automotive electronics savvy. The good news is that there is a ton of info online (sometimes too much) about megasquirt and there are forums full of good people trying to help.

After a little bit of reading it strikes me that it is an overly complicated subject - seems to have suffered from typical interference from the IT sector => "treat it as a black box" BS

Right I'm on a mission - but it looks like it will be a long term one.

Thanks for the feedback chaps