engine hicup

[stevo]

whats happening is the engine jerks every so often, at any rev, wether its being driven or at idle
i thought this was due to a split hose on the idle control valve but i sorted that today and the problems still there, i also noticed the oil filler neck is slightly sucking in so checked the breathers and they're clear. they're doesnt apear to be any leaks anywhere either. ive also tried disconnecting the battery for an hour but still nothing
there doesnt seem to be any loss of power otherwise

does this sound familiar to anyone?
please help

its a 318i m40

[orkboss]

Is this a jerk or just an odd miss when the engine fails to fire. Mine has done this.

[stevo]

its like it gets no feul for a second, as if ive took my foot off the throttle and press it again straight away, or if its ideling the revs will suddenly dip until the engines on the verge of cutting out then return to normal.
think i'll give the fuel filter a check, if thats possible?

[jonmsm]

have you tried looking at the idle control valve??

I am not sure if the e30's have them but the e28's have them and they can cause an irregular idle.

Also, it could be the fuel pump... its possible its on its way out or a bad earth on a power lead for the pump?!

Jon

[stevo]

the ICV looks ok, i'll give the feul pump connections a check and clean up though, never thought of that

[jonbuoy]

What's your car like when starting up from cold?

[stevo]

starts with no problems at all

[E30BeemerLad]

how do i get to the fuel pump on my 325?

In the last week it has suddenly got a lumpy idle and at low speeds with your foot just on the gas it kangaroos a little

[jonbuoy]

Yeah but what about idle? Does it still do it then(idle up and down, and a bit sh*tty til warmed up)?

[stevo]

think its inside the fuel tank

[jonbuoy]

how do i get to the fuel pump on my 325?

In the last week it has suddenly got a lumpy idle and at low speeds with your foot just on the gas it kangaroos a little

Try cleaning your idle control valve

[E30BeemerLad]

what do you do mate, just give it a blast with some carb cleaner?

[stevo]

Yeah but what about idle? Does it still do it then(idle up and down, and a bit sh*tty til warmed up)?

yeah the revs kind of fluctuate a few times on start up but its always done that, this "hiccup" doesnt happen then though

[stevo]

what do you do mate, just give it a blast with some carb cleaner?

think it can be accesed from under the rear seat, not really clued up on it though, and i think the gasket wil need replaced if its removed. just flicking through haynes at the mo'


not reading the post right

[jonbuoy]

Has your car ever overheated at one stage? I have the same problem and have been told to change the temperature senser as this is tell the ecu that the engine is warm when it's actually cold.

[jonbuoy]

what do you do mate, just give it a blast with some carb cleaner?

Yes mate, you are right. Spray cleaner in one end with finger over the other hole, fill it up and give it a good shake. Do this a couple of times and should be ok mate.

[stevo]

Has your car ever overheated at one stage? I have the same problem and have been told to change the temperature senser as this is tell the ecu that the engine is warm when it's actually cold.

a couple of times, but not since last year, this only started happening after i serviced it. is the temp sensor deer?

[jonbuoy]

Same happened with mine really, did'nt start mucking me around till a mth or 2 after it happened. I was gonna change mine today but did'nt get the bloody chance as the bloody father inlaw dragged me up the club, willingly ................not sure about the price tho but make sure you read through your manual about it if your not fluent. Chapter 3-7 Temp gauge sender unit

[E30BeemerLad]

by temp sensor we mean the one on the thermostat housing?

[stevo]

Same happened with mine really, did'nt start mucking me around till a mth or 2 after it happened. I was gonna change mine today but did'nt get the bloody chance as the bloody father inlaw dragged me up the club, willingly ................not sure about the price tho but make sure you read through your manual about it if your not fluent. Chapter 3-7 Temp gauge sender unit

i'll give that a try, must be cheaper than a fuel pump!
cheers for the help dude

[jonbuoy]

by temp sensor we mean the one on the thermostat housing?

As yours is 325 then yes, it's on the thermostat housing but for the M40 it's on the left handside of the head towards the bolkhead

[jonbuoy]

Same happened with mine really, did'nt start mucking me around till a mth or 2 after it happened. I was gonna change mine today but did'nt get the bloody chance as the bloody father inlaw dragged me up the club, willingly ................not sure about the price tho but make sure you read through your manual about it if your not fluent. Chapter 3-7 Temp gauge sender unit

i'll give that a try, must be cheaper than a fuel pump!
cheers for the help dude

No probs, always here to help. Hope it solves your problems, let me know how you get on, if i need to put my thinking cap on again

[Skip]

Did you sort this Stevo - my 316i is doing pretty much the same thing...

[Widge]

I think the problem is with fuelling, and is down to one of the DME (I think they are called) relays on the front passenger wing in the engine bay, I changed mine to 3 from a scrap car and it solved my intermittent jerking problem.

[Brianmoooore]

by temp sensor we mean the one on the thermostat housing?

As yours is 325 then yes, it's on the thermostat housing but for the M40 it's on the left handside of the head towards the bolkhead

M40 blue sensor is hidden under the inlet manifold about half way along.IIRC, the M10 one is on the top of the head near the bulkhead.(or is that the temp gauge sender?)