No Spark at Coil.....ugh

Hello Folks,

My 95 Camry (135k, 4 cyl) cranks strong but will not start, I determined there was no spark through the wires so I checked for voltage to the coil, only .2 volts, I understand that it should read

12+ like a straight reading on my battery. I just re-installed this engine and so clearly I have monkeyed up something somewhere, I'm guessing it is not grounded properly somewhere, or a short, etc etc. Any ideas what I should keep an eye out for? Short of pulling the wiring harness out, splitting it open and checking the wires are there any other things I have over looked that I should try? Much thanks for any ideas! I'm running out of hair to pull out!!

Zach

Reply to
arynday
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When you measure primary voltage at the coil, where are you grounding the negative lead to the volt meter? What is the voltage if you put the negative meter lead on a chassis ground or the battery negative terminal? If it is still .2 volts, then the problem probably not due to improper grounding, more likely a poor or loose connection. If the harness is no physically damaged or stretched, check the harness connectors to make sure they are tight, and that the individual pins in the connector are not corroded or backed out of the connector.

You mentioned that you just re-installed the engine - did it ever run properly? Are you sure that cam timing is correct?

Reply to
Ray O

Hi Ray-

When I checked the voltage I grounded the negative lead on the engine block and then the chassis, .2 on both. The car did run correctly, I pulled the engine out to change the rear main seal and to get a closer look at where it was leaking oil. While I had it out I just changed the timing belt, I had everything lined up, camshaft at

12 o'clock with the rotor on the 1st wire position, crankshaft was at TDC.

I played around with the ohm/resistance on the coil itself and it looked to be within the accepted range, I then undid the power lead to the unit and was stumped to find only .2 volts. I've started disassembly again to take a look at the wiring harness, many of the connectors seem to be one piece units, are they meant to be disassembled?

Thanks for the ideas!

Zach

Reply to
arynday

If you checked voltage with the negative lead of the volt meter on chassis ground, then a bad ground is not the problem. Check all of the fuses in the engine compartment to make sure none are bad.

The connectors are not meant to be disassembled, but the pins inside the connector can sometimes get bent or work itself loose. Look inside the connector to make sure the pins are not bent or corroded, and you can push (don't pull) on the wire from the back side of the connector to make sure they are tight.

I assume that you are measuring voltage with the ignition switch on. How are you measuring voltage? Are you disconnecting the connector from the coil and measuring from the side of the connector that plugs into the coil? Is there any difference if you connect the connector and back-probe the positive pin? You can make up a jumper wire with an in-line fuse and a narrow pin at the end and try feeding 12 volts from the battery to the back of the connector and see if the car starts. If it does, then you have a bad connection in the harness. To find the break in the connection, look at the color and tracer pattern in the wire where it plugs into the coil, then follow the wire loom back to the next connector and look for the same color and pattern wire at the other end of the loom. Measure voltage at the other end of the loom until you find 12 volts. The break will be between the point where you found 12 volts and the coil.

When you changed the timing belt, are you sure that cylinder #1 at TDC compression and not exhaust?

Reply to
Ray O

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