Long cranking before it starts

[1990m3]

On cold start up it cranks in about 4 turns then starts right up, acts like a normal e36 would on startup. When the car is warm or after sitting for a few minutes between startup it sometimes seems like it will crank for 10 seconds before startup, then it fires. It eventually starts every time but sometimes seems like it takes awfully long.

Could this be a secondary fuel pump? Already replaced my main fuel pump (drivers side), 24lb injectors, new fuel pressure regulator, and fuel filter during the swap. Sometimes it's worse than others, looking for some tips...

thanks

[SchnellerVert]

Are the injectors leaking? Were they new or used?

[tjhartge]

fuel pressure regulator, check it out, and the valve that closes the fuel pump, as the whole fuel line is pressured

[1990m3]

fuel injectors were new with the swap. I replaced the fuel pressure regulator too but it had the same start up problem before and after the new regulator. I don't know about the valve that closes the fuel pump, where can I find that? I only replaced the primary fuel pump after I did the swap.

[PiercedE30]

it has to do with the fuel pump, the pressure accumulator valve or something.

[tjhartge]

fuel injectors were new with the swap. I replaced the fuel pressure regulator too but it had the same start up problem before and after the new regulator. I don't know about the valve that closes the fuel pump, where can I find that? I only replaced the primary fuel pump after I did the swap.

the fuel pump has either a built-in valve or external valve thing

this valve thing closes when the pump shuts off, thus maintaining the pressure within the fuel lines, while the other end of the line is the pressure regulator

i'm not too sure about primary and secondary pumps and which ones has the valve thing, but on models with just one pump in the tank, or pump outside the tank(just 1 pump) the valve shud be located just after the fuel line going out to the engine

you could essentially add one or two inline with the fuel lines, and its more of a one-way valve, so it actually won't cause any detrimental fuel pressure problems thats outgoing to the fuel rail

[1990m3]

think i got it straightened out yesterday. Seems there was a leak in my intake system. So far the car hasn't been cranking funny anymore, but it's only been a day. I know it seems odd, but I think the issue is better, the car idles more smoothly also...go figure :)

[Bennetts22@aol.com]

88 to 91 only had the main pump in the tank. No second pump. was it a brand new reg.

[1990m3]

yes, brand new regulator, brand new pump, brand new injectors, brand new filter. Old engine.

[tjhartge]

yes, brand new regulator, brand new pump, brand new injectors, brand new filter. Old engine.

yeah, old and cracked air/vaccum hoses do give these symptoms at times

check your hoses again , just incase the cracked was temporarily closed

i would change the hard ones and those that have hairline cracks and of course not to mention the ones that dissintegrates when you touch them......

[aeryk7]

I am having this same issue. It is intermittent for me too sometimes it will crank right up other times it will crank 5 times or so then start up sometimes i will just turn off the ignition and start over and it will always crank right up on the first attempt of the second key turn. Sometimes it will crank first time in the morning sometimes it wont .I am also encountering the infamous sputtering in the morning but i didnt used to.

Funny thing is today i was under the hood doing some idle revs and i thought i heard a slight vacuum leak low whistling sound in this case from under the manifold but i brushed it off thinking it was just the air entering the manifold.

[1990m3]

don't seem to be any cracked hoses that I can tell. I replaced a bunch of them before the motor went in and it idles smooth as silk once it runs. Aeryk7 and I sound like we have the same problem more or less. we also both started with 318is' if that might matter for some reason

[aeryk7]

I have new hoses around the ICV and a new FPR after replacing it thinking that was the culprit.

[tjhartge]

I have new hoses around the ICV and a new FPR after replacing it thinking that was the culprit.

get some carb cleaner , let the car idle, the spray it near to where you heard the sound of the vaccum leak
if car sputters when you spray it near the sound, you may have a vaccum leak, small enough to cause this fluctuations in idling

a friend of mine had a cracked intake manifold on the underside, it was not untill the manifold was taken off ,only then the crack was noticed, replaced the manifold, and idle is now smoother ,much smoother then silk.......

theory is that when engine is hot, material expansion will eventuallly cover any gaps that maybe present, so when its all warmed up, you may not find that small elusive hole, but the carb cleaner may just work

[Bennetts22@aol.com]

get some carb cleaner , let the car idle, the spray it near to where you heard the sound of the vaccum leak
if car sputters when you spray it near the sound, you may have a vaccum leak, small enough to cause this fluctuations in idling

a friend of mine had a cracked intake manifold on the underside, it was not untill the manifold was taken off ,only then the crack was noticed, replaced the manifold, and idle is now smoother ,much smoother then silk.......

theory is that when engine is hot, material expansion will eventuallly cover any gaps that maybe present, so when its all warmed up, you may not find that small elusive hole, but the carb cleaner may just work

great idea!!! Never heard of that trick