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Discussion Starter · #1 ·
I have positioned the etch mark on the flywheel of my '88 Spider to the 12:00 position, with crankshaft at TDC, but no.1 cylinder does not fire properly.
At the 12:00 position, the magnetic pin on the flywheel is at approximately the 2:00 position,about 60 degrees away from the sensor on bell housing, at approximately the 4:00 position. Could this be causing the problem with no. 1 cylinder not firing properly?
What is the proper position of magnetic relative to the bottom sensor on the bell housing?
Do I have the flywheel aligned properly and something else is causing the problem.
Thank you.
 

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Your first sentence is a bit confusing "with crankshaft at TDC, but no. 1 cylinder does not fire properly." Are you saying that you are getting spark on the other cylinders just not No. 1, or do you have no spark at all? Or are you getting spark, but not at the right time? And when you say "crankshaft at TDC," assuming that you are referring to the piston position in cylinder no. 1, which direction are the cam lobes for that cylinder pointing? And what direction is the distributor rotor pointing?
 

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Discussion Starter · #3 ·
Everything, cams (front lobes splayed out), distributor (rotor on the mark), crankshaft on the F mark.
Put flywheel back on in, supposed, proper position. No. has spark, but does not fire properly.
Thanks.
 

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If the flywheel was put on with the timing mark at 12:00, that's all you need to do there. Have you confirmed that the lower flywheel sensor is connected to the gray harness connector and the upper sensor is connected to the black harness connector?
 

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To leave no stone unturned, there are two sensors. They are identical but must be connected to the wire harness correctly. The wire harness connectors are color coded black (upper) & gray (lower). One measures speed (rpm) by sensing the teeth on the ring gear. The other measures position (timing) by sensing the nib in the edge of the flywheel.
1646675
 

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And to turn the stone over even further, I suggest you remove the sensors for a physical inspection. I have seen a sensor that tested good with the ohm meter but the engine would not start. When we removed it there was a dent in the end. We replaced it with a known-good (used) sensor and the engine started right up.
 

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All of the grounds connected well? You can get a no-start condition with bad grounds. (After changing the main fuel pump on the side of the road, I found out that my problem was that I hadn't tightened the grounds that are on the intake manifold near cylinder 4.).
 

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Discussion Starter · #12 ·
And to turn the stone over even further, I suggest you remove the sensors for a physical inspection. I have seen a sensor that tested good with the ohm meter but the engine would not start. When we removed it there was a dent in the end. We replaced it with a known-good (used) sensor and the engine started right up.
Good idea. Thank you.
 

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Discussion Starter · #13 ·
All of the grounds connected well? You can get a no-start condition with bad grounds. (After changing the main fuel pump on the side of the road, I found out that my problem was that I hadn't tightened the grounds that are on the intake manifold near cylinder 4.).
Yes, those are tight as are the ones on Alternate Air Flow.
Thank you.
 

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If you only have a problem with spark on one cylinder, the problem is between the distributor and that spark plug. If all of the contacts on the inside of the distributor cap are good, then the problem may be the wire (these can break internally, especially some aftermarket wires), or the spark plug itself. Or it is a fuel problem with the injector (clogged or inop?)
 

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could be as simple as a bad spark plug, or a bad lead.

I'd simply swop sparkplugs over between #1 & #2........has the 'no spark' situation now moved to #2?
also swop over 2 of the leads, see if the 'no spark' follows that...

no, then check the cap and rotor.
 

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The TDC flywheel bolt hole has the bolt threads recessed about an 1/8 of an inch into the hole. Line that hole up with the mark on the outside of the rim and your flywheel will be timed correctly.
 
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