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Newbie timing belt help please

 
Old 07-10-2010, 12:12 PM
  #16  
GlenL
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Let's relax with the hysterics.

The mechanic is crappy and lazy but not totally wrong. Tweaking that tension to get the light off is a pain and he doesn't want to do it again after the belt relaxes. The fact is that the newer belts don't relax much at all and after 100 miles the tension will be stable.

You need a "Kempf" tool, a 10mm socket, a 17mm wrench and about a half hour and you can tension that thing yourself. You'll feel a good deal of satisfaction when you're done and when you tell that mechanic you did it yourself and you won't be back, ever.
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Old 07-10-2010, 12:17 PM
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It could also be like an 85 I've got here. The tension is correct but on the tensioner arm, the metal contact is busted so it has lost ground, keeping the circuit open. The repair is to pull the entire front off and putting a new tensioner arm on it.

Have someone that knows what he is looking at, if that is the case, then you know what your choices are.
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Old 07-10-2010, 12:19 PM
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Originally Posted by SeanR View Post
It could also be like an 85 I've got here. The tension is correct but on the tensioner arm, the metal contact is busted so it has lost ground, keeping the circuit open.
Good point. Those bits are liable to get messed up on a belt change. Gotta get the center cover off to diagnose and that's a lot of work.

If the light doesn't go off with the tension set tight, or a bit high, then you'll know something is wrong.
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Old 07-10-2010, 12:22 PM
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Also, the harness might be messed up. An easy check is to pull the wire off the cover (behind the dipstick) and ground that. Run the car for 3-5 minutes. If the light does not come on, that will tell you to look behind the front cover.
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Old 07-10-2010, 01:15 PM
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Ok Ive pulled the wire what should i ground it to? (sorry but like I said I'm a newbie)
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Old 07-10-2010, 01:20 PM
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The engine block or the body of the car. It's all connected together.
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Old 07-10-2010, 01:38 PM
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Originally Posted by GlenL View Post
Let's relax with the hysterics.

The mechanic is crappy and lazy but not totally wrong. Tweaking that tension to get the light off is a pain and he doesn't want to do it again after the belt relaxes. The fact is that the newer belts don't relax much at all and after 100 miles the tension will be stable.

You need a "Kempf" tool, a 10mm socket, a 17mm wrench and about a half hour and you can tension that thing yourself. You'll feel a good deal of satisfaction when you're done and when you tell that mechanic you did it yourself and you won't be back, ever.
Glen: I'm all for not panicking unnecessarily, but he needs a new mechanic regardless. You seem to be saying his mechanic is banking on this being initial belt stretch, hopefully not enough to be dangerous. Unless he set the tension on the real low side for some reason, I can't say I've seen this happen. He doesn't sound smart enough from the "wait 5K miles" thing to think this much. There could be other faults, like bent should bolts, etc. Or it might be as simple as a broken warning system wire or loose connector. Who really knows?
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Old 07-10-2010, 01:41 PM
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Ok I did that and the belt tension light still came on. What's next?
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Old 07-10-2010, 01:44 PM
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Originally Posted by walstib View Post
Ok I did that and the belt tension light still came on. What's next?
The connector needs to be held to the block for a long time (minutes) while the engine is running and should be in contact before starting the car. Did you do that?
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Old 07-10-2010, 01:50 PM
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I would repeat the test a few times, at different ground points. Sometimes getting a good ground can be tough with engine vibration etc.

I stick a piece of wire in the harness connector and use alligator clips holding it to ground. Use a multimeter to ensure you have a constant ground and have zero resistance in the connection. Start up and repeat.
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Old 07-10-2010, 01:50 PM
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Great minor troublshooting.

Won't tell us anything, unfortunately, Glen
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Old 07-10-2010, 02:00 PM
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Originally Posted by Landseer View Post
Great minor troublshooting.

Won't tell us anything, unfortunately, Glen
What is that about?

It will say if the light will ever go off.

Offer some practical advice instead of sniping.
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Old 07-10-2010, 02:06 PM
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It will tell us where a fault is. May be multiple ones.

What it won't tell us is if the belt is actually tensioned properly, but narrows down possible issues.

I would still have someone who KNOWS 928's take a look at the tension. If the mechanic was using a proper tension tool, then you should be good to go.
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Old 07-10-2010, 02:06 PM
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yes I did and the light still is coming on
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Old 07-10-2010, 02:10 PM
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Originally Posted by walstib View Post
yes I did and the light still is coming on
There is a break in the wire someplace in the harness. Take a look at the wire you can see, and check for breaks/chafes on it.

You should go to the jump post and take a look at the 14 pin connector and ensure that it is corrosion free and in good shape. Tearing in to the harness its self is something you might need to do to find the break.

Do you have the Work Shop Manuals (WSM's)? If not, and you plan on working on it yourself, please get a copy on CD or search here for links. They will save you a lot of time and grief.
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