Anybody have a problem with Tunerstudio MS lite disconnecting when engine is started. With key on engine off it will connect up and I can burn changes, start engine up and within 5 seconds it disconnects. Last year when I was running fuel only it would intermittenly do this, now that i'm running ignition it disconnects every time the engine starts. Any thoughts welcome

Sounds like a noise issue. I'd first make sure you're running good resistor type plugs and the plug wires are in good shape.

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"Mad Scientist" Matt Cramer
'66 Dart - turbocharged 225
My blog - Mad Scientist Matt's Lair

You could also have alot of electrical noise from a bad alternator diode. Set your voltmeter to AC scale & measure across the battery terminals with engine running. rev the eng slowly & take a steady reading. Turn on lights, blower, etc, - rev slowly & take another reading. 100mV or more AC ripple might indicate an alternator problem. Try disconnecting the regulator leads at the alt- run it & see if your communication glitch goes away.

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63 Valiant Wagon
225 - 4 bbl

What year is your car? I have seen this when the 12 volts used is timed to cut of f.door buzzer ect..

Yes, Does the computer shut down or does it simply loose the connection with the ECU? I think mine lost its connection when it went to sleep in battery save mode, however, that seems very early for that. MIne would work for 10 or 15 minutes before that would happen. How are you powering your laptop? I eventually bought an AC converter to plug mine into.

Sam

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I seem to have solved problem, added a capacitor at the power wire at coil pack, had it running for about 15 min with laptop reading OK with no problems, capacitor is for a 2000 ford ranger had to order from dealer was $7.00, also had problems with P/S pump,big clip inside can popped out of pump body, lost P/S and made lots off noise,had to fix that before I could work on electrical noise problem

Could you please supply us with a more complete description of where you put the capacitor, and the part you purchased? I have been chasing noise demons for months. Thanks.

Sam

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Sam,

He listed the original application in the post just above your question. Ignitions typically switch the negative side of the coil. The positive side of the coil hooks (perhaps through a fuse) to switched battery positive power. You put the capacitor positive terminal as close to coil positive terminal as you can and other side to ground. Even the factory did this with our stock ignitions.

Pierre, that is a help, but I am pretty sure if I go in to the Ford dealer and ask for a capacitor for a Ford Ranger, they are going to look at me like I am from Mars, and speaking Martian. In fact, most dealers seem to need a vin number to even begin hearing you. I think there is an important nerve connection between the brain and the rest of the body that gets actuated by a VIN number. I do not think I would even get as far as "What capacitor are you looking for?" Instead I would hear, "I cannot look anything up without a VIN number", spoken in deadpan, robot like inflection. A part number or specific function application would make the search easier.

I think I have put a ferrite choke on my coil feed at this point, but think I have not tried a capacitor there. I have a number of them applied so far. Now that it is Spring, I will start working on this again.

Sam

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He's talking about a "radio noise capacitor" or "radio suppression filter"- it mounts to the ignition coil pack on a 2000 Ford Ranger 3.0L V6 (actually almost on any Ford waste-spark coil pack car or truck - like 1995 up through 2003 or so) . It would be easy to find in a boneyard if you happen to go there anyway.

Silly question- would a breaker point condensor do any good as a noise suppressor? (don't know the uFarad value)

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63 Valiant Wagon
225 - 4 bbl

Lol Sam... any well versed parts guy, if you tell him "capacitor hanging off ignition coil" will be able to do the deed. If he asks for a VIN, ask to speak to someone else. Modern dealers have part breakdowns of each major system so you can just point and say gimmi one of those without even having a part number or name.

I don't know what the value of a breaker point condenser is - this isn't an exact science. Anything from several 10's to hundreds of uF will be fine as long as the voltage rating provides a safe margin, say 16 or 20v.

Check here for an informative post with part numbers and here for a picture.

Ford capacitor part # is F67Z188
32-BA

Thanks. Is that part on your slant? Are you firing your plugs with a coil pack, or is that a photo of a Ford engine bay?
Sam

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