Help with checking timing on 4.9liter

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Jan 20, 2003 | 08:42 PM

boris

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Joined: Jun 2001

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Help with checking timing on 4.9liter

Hello.....can someone give me a little help on using a timing light to check timing on my 1990 f150 4x4 with 4.9 300 6 cylinder??? I have a manual but still not quite sure on where to hook up all the cables?? In the manual it also states to disconnect vacuum to the distributor, is this true?? I have the dristributor with the control module mounted right on the side of it. Just want to make sure I do everything right the first time!! Thanks

Jan 20, 2003 | 10:25 PM

fastf150

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Help with checking timing on 4.9liter

ok, the red clamp goes on to the pos on your batt. the black goes on negative. The "pickup" is what detects timing, it should be totally different from the other two. This goes on to the no. 1 spark plug wire. be sure to keep the clamp away from any other plug wire.
you do need to unplug the distributor advance vacuum hose, but be sure and plug the hose! so you have no vacuum leak.
this is because you want to set the timing at what is called "initail advance". now point the timing light at your timing marks (while engine is running) and make any adjustment necessary. Make sure your truck is idling at proper speed when you adjust timing.

Jan 20, 2003 | 11:51 PM

83Steve

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Joined: Jan 2003

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From: Memphis, TN

Help with checking timing on 4.9liter

a '90 EFI doesn't have a vacuum advance on the distributor. Look on the emissions sticker on the hood/core support/air cleaner for the procedure. The SPOUT (SPark OUT shorting plug) is a little gray plastic **** that's taped up inside the wiring harness somewhere near the ignition module with 2 pink wires going to it. Just pull it straight out while you're setting the timing.