Losing Power
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Forum Name: Irish Forum
Forum Discription: where Irish members can discuss upcoming events, etc.
URL: http://www.bavarian-board.co.uk/forum_posts.asp?TID=27463
Printed Date: 29-April-2024 at 09:06
Topic: Losing Power
Posted By: Jumbo
Subject: Losing Power
Date Posted: 20-February-2006 at 04:13
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Anyone know what could be wrong Every now and again while driving along I seem to lose power in my car. When I put my foot on the throtle there is very little response from the engine.. This morning while stopped in traffic the engine cut out altogether but started again immediately.
Any ideas?
Thanks
Brian ------------- Brian... |
Replies:
Posted By: Eamo
Date Posted: 20-February-2006 at 04:25
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what car you got???
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Posted By: llatsni
Date Posted: 20-February-2006 at 04:27
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could be a host of things! but sounds generally speaking like a fueling problem.
What car exactly is it? Has it been serviced recently? My suspicion would edge toward (ordered cheap to expensive): - dirty throttle body(ies) - Lamda sensor - air flow meter but then it could be something simple like a fuel filter! If its a modern car get it to a dealer to diagnose on the computers. If older go to a beamer specialist or DIY. Paul ------------- 1996 e34 525i SE Touring [uberwagon!] 1992 e36 325i Coupe [track car] 1998 e36 316i SE Saloon [sold... but missed] |
Posted By: Kin Mak
Date Posted: 20-February-2006 at 04:50
Wrong gear? 
------------- http://www.kinmak.com - KinMak.com - http://www.elara.ie - Elara Online |
Posted By: Jumbo
Date Posted: 20-February-2006 at 05:00
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It's a 1997 520i.. It was serviced 3,000 miles ago. Now if it was my wife driving i'd probably agree with KIN..... ------------- Brian... |
Posted By: Fey!
Date Posted: 20-February-2006 at 06:16
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Brian - it sounds like a problem I had with an air mass flow sensor (or something that sounds like that!) last year on my e39. The bad news is that if it is, it cost me about €500 to get sorted! It should show up on a diagnostic report - could be the cheapest way to verify. ------------- "http://www.tempoantiques.com""> 
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Posted By: Kin Mak
Date Posted: 20-February-2006 at 06:19
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Tell me if you need MAFs, a guy on the M5 Board sells the sensors by
themselves rather than replacing the whole enclosure. I think all E39s
use the same MAFs. Costs less than €100 if you only need one. ------------- http://www.kinmak.com - KinMak.com - http://www.elara.ie - Elara Online |
Posted By: Kin Mak
Date Posted: 20-February-2006 at 06:21
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Oh yeah... here is a way to test your MAFs. What BMW do you have? http://www.e39m5.com/e39m5OBCtest.html - http://www.e39m5.com/e39m5OBCtest.html ------------- http://www.kinmak.com - KinMak.com - http://www.elara.ie - Elara Online |
Posted By: Jumbo
Date Posted: 20-February-2006 at 07:20
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Would this MAF affect my fuel comsumption as I have noticed a drop. Am I doing any damage by driving the car as it is? Kin, it's 1997 E39... if it is the MAF, can an ordinary mechanic do the job or does it have to be a main dealer thanks for your help
Brian
------------- Brian... |
Posted By: llatsni
Date Posted: 20-February-2006 at 07:23
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@Kin: interesting reading that site!
@Jumbo: a "bad" MAF will usually cause over-fuel by design, as under-fuelling would be way more damaging to the engine. But long term over-fuelling will kill the catalytic convertor. ------------- 1996 e34 525i SE Touring [uberwagon!] 1992 e36 325i Coupe [track car] 1998 e36 316i SE Saloon [sold... but missed] |
Posted By: Kin Mak
Date Posted: 20-February-2006 at 07:31
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It is easy to do and you can change it yourself. Bad MAFs are usually dirty MAFs caused by contaminants. This means the reading of airflow is wrong and usually less than what you are getting into the car. This causes the engine to pump less fuel in as it thinks there is less air. This is what causes the loss in power. That is my take on it anyway... ------------- http://www.kinmak.com - KinMak.com - http://www.elara.ie - Elara Online |
Posted By: Jumbo
Date Posted: 20-February-2006 at 07:44
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Can I see the maf from looking into the engine? ------------- Brian... |
Posted By: Kin Mak
Date Posted: 20-February-2006 at 08:09
I have marked the left one in my engine. ------------- http://www.kinmak.com - KinMak.com - http://www.elara.ie - Elara Online |
Posted By: Jumbo
Date Posted: 20-February-2006 at 08:39
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Thanks ------------- Brian... |
Posted By: ivanovoitch
Date Posted: 22-February-2006 at 17:11
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I'd check the HT leads...it just takes a loose one to deliver the symptoms your experiencing.
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Posted By: Andrewf20
Date Posted: 22-February-2006 at 18:01
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I was loosing power on my 1996 323i from a failing / disintegrating cat after 9 years of use. However, unlike yourself, the car consistently felt like having 50% power up to cat replacement, rather than the "now and again" power dips you see. Although, when the cat was hot after a few miles driving the power drop was a little worse again.
------------- Andrew Purcell E36 323i |
Posted By: kbannon
Date Posted: 23-February-2006 at 04:34
The E39 doesn't have HT leads - it uses individual coils ------------- Current: 2009 E60 520d "Sport" tractor Previous: 1989 E30 320i SE 1997 E39 523i 2003 E39 525i Sport Individual |
ivanovoitch wrote:Posted By: ivanovoitch
Date Posted: 23-February-2006 at 17:22
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Yup...had mine replaced two days ago..all four. However alan in AC
mentioned that one of the leads was loose which was contributing to my
intermittent flat spot which is very similar to the problem described. The leads effectively perform the same function as a HT so I described it as that... ------------- |