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View Full Version : 1990 302 - timing light not working?



vincent brick
03-24-2007, 09:10 PM
First off, I feel bad making my first post outside of the newbies section about a non-Mustang. I signed up here because I should be buying a Fox body in the next few weeks, but I don't know where else to turn with this and my roommate suggested I try here.

I'm trying to fix my boss' 1990 302-powered F150. It runs very rough, has no power, erratic idle, smells of gas, and stalls after it warms up. It has a new distributor cap, rotor, plugs, wires and coil. I am trying to check/adjust the timing, but I cannot get the timing light to fire, not even when I try it on the coil wire. I tried randomly rotating the distributor to see if I could improve the situation any without the light, but that didn't help. Regrettably I have little/no prior experience with distributor-equipped vehicles, and up to this point only going off of advice given from my Dad and his ASE-certified buddy who both live 5 hours away. Everyone I have asked about this is stumped.

The timing light should be good, it's a brand new top-of-the-line Craftsman and it worked fine when I checked it on another car.

Does anyone have any ideas? Thank you so much for any advice I receive.

Vinny

Shortbus
03-24-2007, 10:33 PM
Sounds like the light is bad. Check the fuse, and check the bulb.

theyallslow
03-24-2007, 10:50 PM
ok, first stop and think alittle. you sound like you know somthing about cars.
start with what you know. is there is a plug that needs to be unpluged before you can change the timing. and if you need more help try asking one question at a time.

ricmcusa
03-25-2007, 12:05 AM
I am not trying to diagnose this over the net. But one thing is for sure if the light worked fine on another vehicle and doesn't on this one. I would say the spark could be to weak to flash the light. Also check the battery terminals. Are they tight and not corroded? Is the alternator charging? There could be alot of reasons why this is. Ever have a miss on a cylinder and verify which one with a timing light? The missing cylinder will make the light flash erratically or not at all. Maybe the ignition module is taking a crap.That would explain why it is worse when it warms up? Is the ground and 12 volt wires to the coil in good condition? Check the basics first is all I am sayin. Hope my 2 cents helps.
Oh B.T.W. I wouldn't feel bad for this being your first post. There are alot of good people on this site always happy to lend a hand.

Black Horse
03-25-2007, 07:53 AM
A couple of ways to diagnose the light - try hoooking it up to another battery (different source of power - even in a different car). Also try cliping it onto another plug wire (even if it is not #1). If you can get it working but the #1 does not work check your plug wire first, then I (like ricmcusa said) would be suspect of the ignition module/hall effect sensor.

Welcome to the site - lots of good info here and folks that will lend a hand if you need - there is always at least one of us that has had the same obstacle that you have reached! If nothing else we can all scratch our heads together!

mustangie
03-25-2007, 11:01 AM
if it is a top of the line then it should have a switch from rpm to flash digital ?is the screen blank or just no flash. my matco light wires come unpluged from time to time at a connector in the middle of the battery leads.

vincent brick
03-25-2007, 12:40 PM
Sorry for the complicated question. It was meant as only one, why the timing light won't work, but I tried to sneak in some about the root problem I am trying to diagnose to see if anyone had any ideas. Sorry about that.

Battery terminals look fairly new, and are tight with no corrosion. I have no reason to believe there is an alternator or other charging system issue, anything specific to these motors I should look for?

Wires to the coil and the connector looked fine. One thing I did forget though, was after two tries I could not find a spark plug wire set that had the right coil wire, so the coil wire to the distributor is questionable. Does anyone know if I can buy a separate coil wire anywhere? The coil wire on this motor has an odd connector with a clip on the coil end of it.

I tried the light on 3 different plug wires (1, 2 and 6 if it matters), as well as the coil wire. About the spark being too weak, we suspected that, which led to me changing the coil out.

Maybe the timing light I got wasn't "top of the line," all I know is it was the nicest Craftsman model they had when I looked. No digital display, just a timing advance knob. Sorry, I am new to the world of mechanically adjustable ignition timing.

Where is the ignition module/hall effect sensor located? Are these two separate units? I'm googling these on my own right now, but figured I'd ask here as well.

Since I am buying a Fox body in the next few weeks, I'm gonna break down and buy a Chiltons or Haynes manual and see if that has any info that would carry over.

Thanks so much so far guys, I appreciate the warm welcome.

Vinny

mustang8998
03-26-2007, 09:37 PM
I would just try another timing light. Just a "plain jane" one. I can't think of any other reason, for it not to work (that has already been covered).