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> 3.2 Conversion; No Spark, Help!, This was supposed to be easy.
ninepfourteen
post Jan 30 2007, 04:55 PM
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Give us a place to start to trouble shoot.

Not sure which flywheel sensor connects where, but doesn't fire hooked either way.

We are not even sure of wiring at this point, although all the Bently checks on the DME plug seem right.

Thoughts? Thanks.
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dr914@autoatlanta.com
post Jan 30 2007, 06:09 PM
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QUOTE(ninepfourteen @ Jan 30 2007, 02:55 PM) *

Give us a place to start to trouble shoot.

Not sure which flywheel sensor connects where, but doesn't fire hooked either way.

We are not even sure of wiring at this point, although all the Bently checks on the DME plug seem right.

Thoughts? Thanks.


I do not know where you are in the installation but for a regular 911 if the fuel pump is running when one is cranking then check the pegs in the flywheel and the two sensors for induced voltage when the car is cranked
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ninepfourteen
post Jan 30 2007, 06:17 PM
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Have voltage at the DME plug contacts for both sensors.


QUOTE(dr914@autoatlanta.com @ Jan 30 2007, 07:09 PM) *

QUOTE(ninepfourteen @ Jan 30 2007, 02:55 PM) *

Give us a place to start to trouble shoot.

Not sure which flywheel sensor connects where, but doesn't fire hooked either way.

We are not even sure of wiring at this point, although all the Bently checks on the DME plug seem right.

Thoughts? Thanks.


I do not know where you are in the installation but for a regular 911 if the fuel pump is running when one is cranking then check the pegs in the flywheel and the two sensors for induced voltage when the car is cranked
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ClayPerrine
post Jan 30 2007, 08:32 PM
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Without the wiring diagram, I can't give you an exact solution... but I would suggest that you check the DME relay and the power leads to it. If it fails, everything stops.
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dflesburg
post Jan 30 2007, 08:43 PM
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Sometimes people get the two black plugs in the set of three (two black, one gray) reversed...
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John
post Jan 30 2007, 11:28 PM
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Do you have fuel pressure?

Is there voltage at the coil while cranking?

Does the fuel pump run while cranking?

Do you feel the idle stabilizer buzzing when the ignition is turned to the "on" position (no cranking)?

The DME relay feeds power to both the fuel pump and the DME.

I know on the last one I did, I had the two crank sensors swapped and it would not fire. I swapped them and it fired right up.

Keep us posted.
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736conver
post Jan 31 2007, 01:30 AM
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The fun of trouble shooting a DME 3.2. (IMG:style_emoticons/default/beer3.gif)

When I had this same exact problem, mine was coil related. I was getting power in the key on position but not the starting/cranking position. Car would actually start sometimes when I stop cranking and it went into the on position. Confused the hell out of me for a couple of hours.
Hook your meter up to the coil and see if its getting power in the start as well as the on postion.
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ninepfourteen
post Jan 31 2007, 05:14 AM
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DME relay works
have fuel pressure
pump runs, but need to check it during cranking
have voltage at coil (I think we checked during cranking)will double check
need to check idle stabilizer
have switched crank sensor leads, made no difference

do you mean you switched leads or the sensors?

Thanks as usual guys.

Fred
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John
post Jan 31 2007, 11:10 AM
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I switched the two leads where the harness plugs together. One sensor only senses a single setscrew on the flywheel (Refrence) and the other only senses the teeth on the flywheel (Speed). With those two swapped, it won't run.

You do need to check for voltage at the coil during cranking. Without that, the car won't run.

With a timing light hooked up to the coil wire, you can determine if sparks are leaving the coil.

Verify if you are getting a spark there first, then go to individual plug wires. It may be a cap or rotor...

The check of the idle stabilizer buzzing with the key on just verifies that there is power to the dme sensors on the engine (verifies the dme relay is working).

Got any pics of your wiring?
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John
post Jan 31 2007, 11:14 AM
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Another area to check is the 3 gobs of ground wires that are supposed to ground to the intake manifold. Sometimes a wire in one of the 3 groups corrodes and is no longer grounded. These can cause all sorts of issues.
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ninepfourteen
post Jan 31 2007, 11:29 AM
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It Lives!

Hot wire to #4 DME terminal was connected hot instead of switched.

Thanks for all the help guys.

On to the next problem, whatever that is.

Fred
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John
post Jan 31 2007, 12:58 PM
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We still want pics!
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