my engine surges when i keep my foot steady on gas and press

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miami325e
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Post Tue Nov 01, 2005 5:48 pm

gradually
could it be
Engine surges while holding accelerator steady
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Intake air leak

Fuel pump faulty

Loose fuel injector electrical connector

Defective ECU
beavis2k4
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Post Tue Nov 01, 2005 7:08 pm

does the car just pick up revs or just basically shudder back and forth?
mines is shuddering and wondered if you had this problem solved?
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haffeel
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Post Tue Nov 01, 2005 9:47 pm

Could you give little more informations?

Like does it happens in the mornings when it cold or damp weather?
Does it happens only you travel less than Kms 40 ?

If the above is true then check the reacent threads with titled

My car dont like cold weather and AFM Symptoms, you might get some ideas.

cheers
Demlotcrew
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Post Tue Nov 01, 2005 9:53 pm

You need injectors like this?

http://wmediavod.coltfrance.com/wmeuros ... 20x240.wmv

Andrew
beavis2k4
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Post Wed Nov 02, 2005 3:34 pm

In my case it will happen at any time/ any weather. but it does generaly happen below 50mph, doesnt matter what gear, if i want to sit at 40mph the cars in fifth my foots resting on accel pedal and the car starts jerking, like it was running out of fuel, i have 1/2 tank in it. Ive just run some fuel injector cleaner through it, you no the stuff, comes from wurth and goes in petrol tank, 1 can / 50l ? Stuff like Redex, although got told this stuff actually worked. Sorry going of on tangent, my problem started before this just thought i would tell you.

Also when i rev the car the lights get brighter, fans blow harder etc any ideas about that one? maybe diif thread though?

thanks in advance,
Callum
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Steviec
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Post Wed Nov 02, 2005 3:47 pm

You could have an alternator/battery problem. Would be worth while getting them check as most places will check for free (Halfords used to).
E30BeemerLad
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Post Wed Nov 02, 2005 3:52 pm

could be injectors like Delmotcrew advised.

My car has similar symptoms recently, when going along a low speeds and very light throttle application in heavy traffic it would jerk back and forth.

Turned out to be the inlet manifold gasket.

Get the car up to running temperature and open the bonnet with the engine still running, spray WD40 or some carb cleaner around the inlet manifold where it bolts to the head, if the idle is restored to a smooth idle then you have found your air leak. This can apply to the whole induction system really.

I don't recall you had mentioned a lumpy uneven idle, but that's what mine was doing.
Hope that helps mate
beavis2k4
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Post Wed Nov 02, 2005 9:52 pm

Will give that a go thanks, oh by the way sorry for the thread hijacking :oops:
Yeah car has a lumpy idle, seems like its hunting for the revs, needle doesnt move though?
might just strip the both manifolds off, clean em up, put new gaskets on, get new air filter, fuel filter, oil change, coolant change and see whats happening after that. I just want to get the car running sweet.
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beavis2k4
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Post Wed Dec 07, 2005 6:13 pm

All sorted now!!

Car jerking while gently pressing accel. car stalling at every junction, cars very rough idle....all gone, the price..... 14 quid, the fix.... air filter hose, the one that attaches it to the throttle body, i couldnt see anything wrong with it but when i started stripping down the intake side i noticed that half the pipe had a huge hole in it, so looked up part number ordered one from Harry Fairbairn BMW in Glasgow late on monday, it came this morning!! (Very quick delivery, especially for where i stay)

So a cheap fix to a few big problems, im well chuffed, cars now running as sweet as a nut!

Just thought i would let you lot know.

:mad: :D
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