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93 FD acting funny

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Old Apr 14, 2015 | 12:22 PM
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93 FD acting funny

My FD is starting to act really funny and not idle at the correct RPM. Is it time for a rebuild or do I still have some time before it needs one?
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Old Apr 14, 2015 | 04:45 PM
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Whoa son. Based on the sketchy info in your post, jumping right to rebuilding is premature. WAY more information is needed before connecting those dots.
Exactly what is it doing? Do you have any engine modifications? Is this just recent. What was happening when it began. What have you done to trouble-shoot?
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Old Apr 14, 2015 | 05:42 PM
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Running funny and a weird idle could be as easy as a spark plug or bad gas. Give us some more info and we'll most likely be able to give you a better idea of where to start.

Have you done a compression test?

Have you checked for a vacuum leak?
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Old Apr 14, 2015 | 06:35 PM
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It idles around 1k-1200 on a fresh start never goes lower until I start using the car. Once I start using the car whenever I brake it goes below 800 sometimes dips as low as 650. I run 93 octane in the car, I have not done a vacuum or compression test yet.
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Old Apr 14, 2015 | 06:52 PM
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So it idles high until it warms up? If so that's normal. And I would say it's a vacuum leak, small. Anything cracked going to the intake manis?
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Old Apr 14, 2015 | 09:15 PM
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Not that I can tell of, but I can't be completely sure I don;t really know what i'm looking for
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Old Apr 15, 2015 | 06:45 AM
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First thought is a vacuum/gasket leak after the throttle-body.
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Old Apr 15, 2015 | 04:56 PM
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Is this something a novice could fix? I'm not very good with cars.
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Old Apr 15, 2015 | 08:47 PM
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^The biggest challenge, at least for me, is finding the issue. Diagnosing. Vacuum leak is my first suspect, but there are other potential causes. If you're not an experienced wrencher, going through the Factory Service Manual and chasing things like this down is probably best left to a trusted shop. No shame in that. Point is, assuming you need a rebuild is way premature.
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Old Apr 16, 2015 | 01:10 AM
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It does sound like some kind of vacuum leak, how many miles on the car, maintenance record?
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Old Apr 16, 2015 | 10:55 AM
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Originally Posted by ZE Power MX6
It does sound like some kind of vacuum leak, how many miles on the car, maintenance record?
I honestly don't know about the mileage as the odometer is out, but I've been changing the oil pretty regularly.
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Old Apr 16, 2015 | 12:51 PM
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Where in Texas are you located?

Depending on the vacuum leak you might be able to hear the leak with the motor running. It will sound like a rushing of air where you normally shouldn't hear rushing air (or sucking air). If you are close to stock the higher idle might be from the Accelerated Warmup System (AWS) until it warms up.
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Old Apr 17, 2015 | 09:30 AM
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Start checking possible vacuum leaks and if nothing run through, the plugs, wires, battery, alternator. If this is your only current issue, most likely not time for a rebuild.
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Old Apr 17, 2015 | 02:04 PM
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I concur with the other posts...simple vac or seal leak. My 93 FD always had a notoriously low idle, but was also ported. Motor is not blown unless it sounds like Harley with a cold, or you have coolant running out of your tailpipe.

Cheers,

AB
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