Fluctuating rpm's

1997 FORD MONDEO
200,000 MILES • 1.8L • 4 CYL • TURBO • 2WD • MANUAL
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ALEKSAJEVTIC91
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I have a problem with my vehicle turbo diesel.

The problem is that when i first start the car it revs normally at about 900 RPM, but when i hit the gas pedal the revs go up and when coming back down they drop to 500 instead of 900. They do come back to 900 after a second but they drop so low as if the car will shut down.

This lasts for a couple of minutes and then goes back to normal. One key thing to note is that while this is happening drive belt that drives alternator is squealing. When squealing stops then things go back to normal.

I am no mechanic but this looks like an alternator problem to me. So can you help me with this one?

The car is an old injector pump diesel and has no electronic controlled units etc.. It should be easy to pinpoint the problem.
May 4, 2019 at 2:13 PM
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SCGRANTURISMO
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Hello,

So if it only happens when the serpentine belt squeals then maybe your serpentine belt tensioner is going out or your serpentine belt might be getting glazed. Check your belt and tensioner and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros
May 6, 2019 at 3:17 AM
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ALEKSAJEVTIC91
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Yeah, was thinking the same. I'l check it by the end of the week and i'l let you know. Thanks for the advice,
May 7, 2019 at 8:35 AM
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STRAILER
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Here is a guide that will help you step by step to replace the belt:

https://www.2carpros.com/articles/replace-serpentine-belt

For the idle fluctuation it sounds like you may have a vacuum leak please run down this guide:

https://www.2carpros.com/articles/serpentine-belt-tensioner-replacement

Please run down these guides and report back.

May 9, 2019 at 1:48 PM
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ALEKSAJEVTIC91
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The problem was in the power steering belt. It was too tight, so it was literally holding back the fuel injector pump due to both being on the same axle. Any way thank you all for the advice, i hope this post will be of some assistance to all those having the similar problem.
May 25, 2019 at 7:59 AM
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STRAILER
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Glad you could get it fixed, that kind of problem can be tough. Please use 2CarPros anytime we are here to help.
May 26, 2019 at 12:56 PM