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Howdy,

My parts order just showed up and I am eager to get this going. Time to learn about surface mount soldering. Any pointers on that would be appreciated. I was an Electronics Technician and Service Engineer back in the days of through hole only circuit boards. Now that I look back, that was a very long time ago.

For EFI experience, I also played with the EFI332 circuits and built a couple of Megasquirts. This project caught my attention as a much newer alternative.

The other item that I spotted was the success running a Dodge Neon. My current project is a 1996 Dodge Caravan with a 2.4L. This is a close cousin to a Neon. It has the same crank trigger pattern and the 8 volt sensors. This rig is a project because it has eaten 3 1/2 ECUs. The half one came from one I fixed by stealing the ignition drivers from one of the earlier dead units.

Other projects I have queued up range from a few air-cooled VWs to a 454 Chevy.

Thanks!

Welcome

Jeffy wrote:Time to learn about surface mount soldering. Any pointers on that would be appreciated.

Soldering paste was given to us by either Gods or Aliens, see also http://rusefi.com/forum/viewtopic.php?f=4&t=425

Did you get some 0805 components? Have you seen http://rusefi.com/wiki/index.php?title=Manual:Hardware_Frankenso_board and http://rusefi.com/images/Frankenso/ for pics of assembled boards? I suggest starting with power supply just to be sure you feed 5v and not 12v into the fragile MAX and FT chips.

Welcome along.

Hmmm, I don't recall 454 being a common size. Perhaps you mean the 70 Chevelle, that had a nice 454. One of my many dreams is a his and her's 70 Chevelle(s).

Hmmm, car that's eating ECU's makes me concerned. I've never seen an OEM ECU actually eat it. I wonder if there is more to the story. Perhaps there is a problem with the setup, or perhaps you are modifying things such that it's no longer OEM.

That is exactly the soldering information I was seeking. I like the coffee cup warmer plus stamp embosser reflow combo. I found one of the stamp embosser (low wattage heat gun) on sale for only $12. I already have the bottom half of a Mr. Coffee that I use for preheating VW timing gears (AKA Mr. Gear Heater).

The 454 (big block) is the same as would show up in your hotrod Chevelle. This one came out of a dually pickup and is going into a motorhome that had a very sick 350 (small block). It is a tight fit, but it does fit.

On this Dodge minivan, the ECU failures have all been in the ignition drivers. It has also displayed odd behavior where the cooling fan comes on at the strangest times and the alternator would squawk the belt and try to stall the engine. I found it most interesting that all three of these functions are controlled by the ECU. A sane person would have sold or scrapped this thing a long time ago. I've never been considered to be in that group. The first round of failures started with a crazy loop of trouble codes that went something like this:
1. Intermittent shutdown of the engine. It would cut out and come back to life.
2. Trouble code said the crank position sensor was bad - replaced it (plus they changed the connector, so had to splice in a new connector to match the new sensor). Intermittent problem still there.
3. Trouble code said the cam position sensor was bad - replaced it (you guessed it, they changed the connector, so had to splice in a new connector to match the new sensor). Intermittent problem still there.
4. Trouble code said the coil pack was bad - replaced it. Intermittent problem still there.
5. Trouble code said the crank position sensor was bad.... HEY WAIT A MINUTE! Intermittent problem still there.
All this fun was followed by a hard failure of the ignition drive circuit. Replaced the ECU with a boneyard item and it was good as new for a couple of years. Repeat that loop a couple more times minus the sensor and coil replacement steps.

Now it it time for something other than the stock ECU. This is totally bone stock at the moment, which is most unusual for me. What I would like to see along the way is control of ignition, fuel, idle, fan, alternator, and maybe cruise control. Yes, that is a lot but I bet it will work.

Thanks.

Sounds like the your problem with the van might be your plug gaps. It's common that your plugs will erode and increase the gaps. The increased gaps will cause the voltage on your primary side of the coil to increase from about 400V to perhaps as high as 600V. However your primary generally has a voltage clamp around 450V to 500V. This clamp will generally cause a weaker spark which you often notice as an occasional skip or misfire. Each time the clamp activates, it will absorb some energy which makes heat. If you have enough clamping events, you'll eventually absorb more heat then it can thermally remove, and you'll damage the ignitors clamping circuit. So yippee not skips as it's now allowing the primary to get up to that desired 600V. The down side is that you are now exceeding the voltage rating of some components. This could potentially turn into excess voltage spikes to the ECU, which could potentially damage the ECU. What I've seem most commonly happen is that the ignition system fails, generally after it has been warmed up. What happens is when the igniter fails to charge and discharge the coil and you don't get enough spark energy.

The solution is typically to fix the spark plug gap, and replace the igniter. AKA new plugs and new coil or ignition module. It's also a good idea to replace the plug wires. It's kind of fustrating as the plug can be rated for something like 100 kmiles but the erosion of the plug fails the igniter after like 50 kmiles. The problem can typically technically be fixed by checking you plug gaps and adjusting them if they are an adjustable style of plug. Many plugs like the Iridium plugs are not adjustable.

About the alternator, I'd need to know more. I would first suggest checking the battery and the motors GND straps. Most auto stores will let you put your battery on a tester. Also you GND straps often get corroded over time which can cause a bunch of problems.

If you don't fix the sparkplug gap and igniter issues before an ECU swap, you'll still get the same problem.

Hot air reflow guns work well for SMT stuff. You can typically get one of them for less then $50 https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#tbm=shop&q=hot%20air%20soldering%20station&tbs=vw%3Al%2Ccat%3A1236%2Cpdtr0%3A58%7C580003%2Cpdtr1%3A63%7C630001%2Cprice%3A1%2Cppr_min%3A%2Cppr_max%3A50