Hi, having a problem sometimes.
Engine Dies immediate after start, have to use throttle and maintain it for 5 secs to not to die.
The engine had a full rebuild, all ignition system was changed. The cleaned the ICV and after that i had no problems for next fiew months.
One day the engine died. I changed the TPS, Crankshaft Sensor, Blue coolant sensor and Fuel Pump, and that solved the problem.
Now sometimes, mostlie when the engine is cold, i have to assist the start with the throttle. This happens once in 20 times, doesn't bother me that much, but i don't want this to escalate to something bigger.
Anyone have a clue ?
1990 316i M40, Engine Dies after start, have to use throttle
Moderator: martauto
I,ll be interested how this progresses . as i have a similar issue on my 1.6 m40 . engine seems to miss a couple of beats after it starts, then pick up o.k . o.k when overnight start, ok after warm start.
seems worst after its been left about 2 hours. and i have to use the throttle for 5-10 seconds.
1989 year.
seems worst after its been left about 2 hours. and i have to use the throttle for 5-10 seconds.
1989 year.
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blood69
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- Location: Funchal, Madeira Island
Update:
Yesterday the same problem happen' a lot, because i had to stop the car a lot of times with 40m to 1h and Half intervals. Had to assist the crank every time with throttle.
I guess the the circumstance you describe "arrisbmw" is the most plausible, this happens when the car is hot.
My recent changes was Bosch TPS, Stark Crankshaft Position Sensor, Bosch Blue coolant sensor and Bosch Fuel Pump.
Does anyone have a clue ?
Yesterday the same problem happen' a lot, because i had to stop the car a lot of times with 40m to 1h and Half intervals. Had to assist the crank every time with throttle.
I guess the the circumstance you describe "arrisbmw" is the most plausible, this happens when the car is hot.
My recent changes was Bosch TPS, Stark Crankshaft Position Sensor, Bosch Blue coolant sensor and Bosch Fuel Pump.
Does anyone have a clue ?
you could have leaking injectors.
what happens is when you stop the engine. petrol leaks out into the inlet manifold and forms a pool of petrol. if its left overnight the petrol evaporates and car starts o.k .
but if you start the car within stay 40 mins or so the petrol is still there and will flood the engine and won,t start without you adding alot more air via the throttle.
it does sound like youve changed evderthing else.
check out youtube plenty vids on there on how to test the injectors once removed.
they not to bad to remove on the m40 as the inlet manifold conveniently splits in half.
I managed to get a second hand one with injectors and had a play with that to understand how it all fits together.
what happens is when you stop the engine. petrol leaks out into the inlet manifold and forms a pool of petrol. if its left overnight the petrol evaporates and car starts o.k .
but if you start the car within stay 40 mins or so the petrol is still there and will flood the engine and won,t start without you adding alot more air via the throttle.
it does sound like youve changed evderthing else.
check out youtube plenty vids on there on how to test the injectors once removed.
they not to bad to remove on the m40 as the inlet manifold conveniently splits in half.
I managed to get a second hand one with injectors and had a play with that to understand how it all fits together.
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blood69
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It's funny you mentioned the leaking injectors, had to reduce half a turn the idle adjustment screw on the AFM, because i had a lot of smoke on cold starts. Didn't mess with the idle TB screw to not have to adjust the TPS switch for idle again.
I'm scared to mess with the idle to much, because i have to pass Emissions on idle on MOT.
But thanks for the injectors tip, gonna investigate that one
I'm scared to mess with the idle to much, because i have to pass Emissions on idle on MOT.
But thanks for the injectors tip, gonna investigate that one
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TurtleDesignTech
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I had a similar problem. Ended up testing every sensor with a tester and cleaning it. Everything was fine apart from a few air leaks I found along the way - mostly around the brake booster.
My car runs rich all the time with fowled plugs on all cylinders. Unlikely to be leaking injectors, as they wouldn't all leak. Especially on a 60k mile car.
I have ended up concluding the culprit is the Fuel Pressure Regulator as the vacuum line reeks of fuel, which means the diaphragm has likely gone.
Took me to couple of weeks to find a replacement at a reasonable price.
Will update in a week or two if it makes any difference or not.
My car runs rich all the time with fowled plugs on all cylinders. Unlikely to be leaking injectors, as they wouldn't all leak. Especially on a 60k mile car.
I have ended up concluding the culprit is the Fuel Pressure Regulator as the vacuum line reeks of fuel, which means the diaphragm has likely gone.
Took me to couple of weeks to find a replacement at a reasonable price.
Will update in a week or two if it makes any difference or not.
NO i,m not saying stuck closed, in fact if they are leaking they leak when they are closed. and engine stops. if that makes sence.blood69 wrote:BTW, if one injector is stuck close, wouldn't the car start and work on 3 cylinders for a few seconds ?
I'm thinking maybe this is going to be a FPR issue.
60,000 miles , millions of pulses , thats about their life . i would have thought.
sound like that is your issue, let us know if the fpr fixed it.
yes it should not smell of fuel , sometimes if really bad fuel can be seen dripping out
sound like that is your issue, let us know if the fpr fixed it.
yes it should not smell of fuel , sometimes if really bad fuel can be seen dripping out
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blood69
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Sorry, i did a bit of a mess saying stuck close. But the idea is, one injector flooding one cylinder, the car should start with no problems i guess. That's why i think is the FPR. Next time i have the opportunity to check the car i'm gonna see if there is fuel inside the FPR vacuum line.arrisbmw wrote:NO i,m not saying stuck closed, in fact if they are leaking they leak when they are closed. and engine stops. if that makes sence.blood69 wrote:BTW, if one injector is stuck close, wouldn't the car start and work on 3 cylinders for a few seconds ?
I'm thinking maybe this is going to be a FPR issue.
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blood69
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Update:
I Manage to inspect the vacuum line of the FPR and smelled a bit like fuel. But wasn't wet with fuel.
On the weekend i drove the car long distances and stopped for 40m to 1 hour before continuing to drive.
Before each startup i steeped on the Throttle for about five seconds and then released before i crank the engine, had no trouble starting at all with no assist of the throttle while cranking.
Don't know if this trick helped to evaporate fuel fumes out of the intake manifold or did something else. Probably did nothing at all and it was just luck and this is an intermittent problem.
I Manage to inspect the vacuum line of the FPR and smelled a bit like fuel. But wasn't wet with fuel.
On the weekend i drove the car long distances and stopped for 40m to 1 hour before continuing to drive.
Before each startup i steeped on the Throttle for about five seconds and then released before i crank the engine, had no trouble starting at all with no assist of the throttle while cranking.
Don't know if this trick helped to evaporate fuel fumes out of the intake manifold or did something else. Probably did nothing at all and it was just luck and this is an intermittent problem.
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TurtleDesignTech
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- Location: Hampshire
Update with new FPR:
Throttle response greatly improved. No hesitation off idle.
Idle is strange - needs more testing. Could just be old fuel or ECU learning again. Difficult to tell as car is SORN.
Plan to send injectors off eventually.
Throttle response greatly improved. No hesitation off idle.
Idle is strange - needs more testing. Could just be old fuel or ECU learning again. Difficult to tell as car is SORN.
Plan to send injectors off eventually.
is your idle up and down or is it steady ? if the icv is working correctly should be up to approx 1400 then slowly drop to 800 when engine warms up and should be steady. if not you idle control valve could need a clean , mine did.
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TurtleDesignTech
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Hovers around 1100 on start and drops to 800. Idle stays pretty much steady thought.
ICV has been cleaned twice.
Taken TPS apart and put back together again - was factory fresh inside. Adjusted to perfection.
MAF seems to be working as it is fine thought the upper rev range. Did clean the temp sensor and inspect flap.
Temperature sensor tested. Working as it should.
New spark plugs recently.
Distributor cap+rotor looks like new inside.
New fuel pump, as last one sounded like commutator on the way out.
New alternator regulator installed. Bushes were worn on old one.
Grounds are all good.
Battery tested. Alright.
CPS and gear wheel is clean. Engine revs happily to red line when warm.
All vacuum leaks are fixed. Tested with smoke test.
I am only left with old fuel and possibly injectors to inspect at this point. However, I still have my suspicions about the ICV working. Difficult to completely count it out without swapping it.
Car might just need to be driven a bit at this point with new fuel, then the ECU can learn how to deal with new FPR.
ICV has been cleaned twice.
Taken TPS apart and put back together again - was factory fresh inside. Adjusted to perfection.
MAF seems to be working as it is fine thought the upper rev range. Did clean the temp sensor and inspect flap.
Temperature sensor tested. Working as it should.
New spark plugs recently.
Distributor cap+rotor looks like new inside.
New fuel pump, as last one sounded like commutator on the way out.
New alternator regulator installed. Bushes were worn on old one.
Grounds are all good.
Battery tested. Alright.
CPS and gear wheel is clean. Engine revs happily to red line when warm.
All vacuum leaks are fixed. Tested with smoke test.
I am only left with old fuel and possibly injectors to inspect at this point. However, I still have my suspicions about the ICV working. Difficult to completely count it out without swapping it.
Car might just need to be driven a bit at this point with new fuel, then the ECU can learn how to deal with new FPR.
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Brianmoooore
- E30 Zone Team Member
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- Joined: Mon Jan 10, 2005 11:00 pm
The only thing opening the throttle does when stating a car is to let it pump fresh air through the engine more easily.
The fuel from a leaking injector won't only affect that cylinder if the inlet valve is closed - it will enrich the air in the whole manifold, so that when an injector fires on another cylinder, the fuel mixture drawn into that cylinder may well be too rich to ignite. With the throttle open, the manifold will be cleared out quicker, allowing the engine to start.
The fuel from a leaking injector won't only affect that cylinder if the inlet valve is closed - it will enrich the air in the whole manifold, so that when an injector fires on another cylinder, the fuel mixture drawn into that cylinder may well be too rich to ignite. With the throttle open, the manifold will be cleared out quicker, allowing the engine to start.