M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Engine + Driveline => Topic started by: longms on October 26, 2009, 01:22:23 PM
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So my m42 is finally running and logging some miles. There is only one issue. When I turn the key the engine turns over for about 4-5 seconds but then fires up every time. The car does this every time. It will not fire right up upon turning the key.
What could be some possible reasons for this issue? What should I be checking? Could MAF sensor do this? Could the fuel lines be losing pressure and that is how long it is taking to build it back up?
Thanks in advance.
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my car does this too! I haven't been able to figure it out, I replaced the starter and it worked for awhile and then right back to doing this.
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Still have not found a fix...fuel sensor has been pressure check and everything and that all seems to be ok.
Yea, my starter is working fine. It turns the motor over strong but it is like the motor has to wake up and build up before it decides to fire. Ignition maybe?????
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New plugs? Wires? I was thinking starter, but you say not that. Fuel pump was my other guess... but you pressure checked fuel system.
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check valve on your fuel return line. Keeps the fuel line pressurized for re-start.
You can just put in a fuel line check valve, call bma and describe what you need.
I paid less than $15 to fix this problem.
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are you referring to the pressure regulator? because that is not $15. that is expensive. :(
where was the part you replaced, if it isn't the regulator? was it near the fuel rail or near the tank?
would you be able to look on realoem and see if they have it listed?
Real OEM VALVES/PIPES OF FUEL INJECTION SYSTEM (http://tinyurl.com/yduaolh)
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My E30 does this as well, but there have been one or two occasions where it didn't start in the moderately cool weather. I cranked it for quite a while and the motor almost caught every few seconds - it would burble like it's about to start and then go back to cranking. 9/10 times it has trouble starting (cold only), it cranks, burbles, and then fires up. I was told I should check my fuel pressure at various places along the lines, but not only am I lazy but I also lack a pressure gauge (and my last experiment with fuel lines ended with gasoline shot down my ear canal... OH the pain). I looked in the Bentley and with the fuel pump working and the ICV mechanically functional (the jury's still out on whether or not it's getting a signal), I decided that the cold start valve might be shot. Granted, the Bentley I have covers my body but no the M42, so I haven't investigated yet.
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Everything electrical (wires, plugs, fuel pump, etc) on the motor is brand new with only about 200 miles of run time.
Will check pressures more extensively.
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check valve on your fuel return line. Keeps the fuel line pressurized for re-start.
You can just put in a fuel line check valve, call bma and describe what you need.
I paid less than $15 to fix this problem.
Where is this said check valve???
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We also installed brand new fuel lines into the system. Could the new lines have anything to do with it?
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Most EFI systems prime the fuel system when you put stage 2 on the ignition. You'll hear the fuel pump whirr a little then stop...
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Explain to me what you mean by putting stage 2 on the ignition???
And I want to know how you got your M42 to 160bhp????????
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He's talking about key position II, where the key is in running position. Position III turns the engine over.
I heard about this check valve to fix warm start problems on my e34. I'm thinking it's installed in the fuel supply line after the high-pressure pump to prevent fuel from bleeding back into the tank.
IIRC it's normally integrated into the pump, but when it goes it's much easier & cheaper to just splice a new one in on the fuel supply side.
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From what I read somewhere on the M42, the fuel pump is only actuated once the starter turns the motor at 125 RPM or something like that. My fuel pump doesn't make a peep with the key in position 2 (in an E30, maybe it changed with the later models)
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Let me double check that. I thought the pump primed the lines on pos II, then started running when the engine spins. I'll re-post later today with my findings.
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Pump doesn't run until crank is turning. We check this with a volt meter.
AndyC... so how did you get the 160hp
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Just skimmed the post, one of my e30's used to have a long crank before it would start, it was never anything that concerned me but after doing some upgrades (removed hose nest/heater plate, 4pintle injectors, cop, k&n, and exhaust) it now wants to fire before I even turn the key. the engine turns over maybe 1/2 of a revolution before it fires, it has the fastest start of any car I have ever seen or owned.
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My pump primes in the #2 position once, I do not know what the conditions are for it. If you try to reprime it does not do it.
Anybody had the line from the pump to the filter break. I noticed mine is and it looks like there is no way to repair it unless you remove the tank, or splice it under the second access port under the seat. The return line looks like it can only be replaced with the tank out.
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My pump primes in the #2 position once, I do not know what the conditions are for it. If you try to reprime it does not do it.
Anybody had the line from the pump to the filter break. I noticed mine is and it looks like there is no way to repair it unless you remove the tank, or splice it under the second access port under the seat. The return line looks like it can only be replaced with the tank out.
I'm interested in this too...not looking forward to dropping the tank if possible, yet might as well replace all those hoses & filter while I'm at it.
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Just skimmed the post, one of my e30's used to have a long crank before it would start, it was never anything that concerned me but after doing some upgrades (removed hose nest/heater plate, 4pintle injectors, cop, k&n, and exhaust) it now wants to fire before I even turn the key. the engine turns over maybe 1/2 of a revolution before it fires, it has the fastest start of any car I have ever seen or owned.
We replaced all the hoses in that mess under the intake, put 4 pintle injectors in, new wires and plugs and a new exhaust...it always fires but takes a little cranking before it fire over
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Relevant to this topic, my junk yard bosch fuel pump died a few weeks ago. When I first installed it, the car would crank a couple seconds and fire right up and idle perfectly (oncie I took care of the ICV issue). A few days before it died it would take longer and longer to to start. It would also not idle as well and I would have to keep my foot on the gas for a minute until it warmed up a little.
New pump and it's back to a couple seconds bfore starting and idling smooth again. I don't want to scare people into thinking their pumps are about to go, but it would be cake easy to put a fuel pressure guage at the fuel line to fuel rail connection just for those of you guys who agonize over that kind of stuff (like me). I have a new pump so I'm not worried. Just remember to get a guage that goes high enough
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that is another thing i did, i put a walbro 255lph fuel pump
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update on my similar issue - my battery was crap. it was good enough to work 98% of the time, but it wasn't cranking it quite fast enough for the fuel pump to kick on. I could hear the relay clicking erratically whilst cranking. new battery and it starts just fine.
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that is another thing i did, i put a walbro 255lph fuel pump
is the walbro pump a dirrect fit?
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Experienced the same simptoms. But not worried about it, the car has been like this for almost two years now since I bought it.
I thought about the fix but still don't know if it would be a good idea to keep the system under constant 3bar pressure even when the car is resting.
4banger: you can see the walbeo inhere http://www.srz.ro/imagini/Walbro%20255%20fuel%20pump.jpg they have made me an offer today for 145 Euro. It is an external pump so no fitting problems should arrise.