HELP!! Car Not Starting.
 

UPDATE: JAN 4/2016 - PROBLEM(S) RESOLVED.

Just wanted to provide an update, it seemed that after the countless hours of troubleshooting the "crank no start" issues has been resolved. There was no "faulty" component that is the only crappy thing, it appears that the problem was resolved during our troubleshooting. We suspect that when we were disconnecting and reconnecting harnesses, fuses, ETC we could have fixed a loose connection somewhere. I know its not the answer we wanted, but hey I will take it! It has been well over a month in cold weather and no issues as of yet!

We also had a battery draw problem, through parasitic tests we determined the issue was with the drivers door actuator. Actuator was replaced and no more issues.

Wanted to thank everyone again for there input and suggestions, was greatly appreciated!


Hello,

Have been running into issues with my X5 and hoping someone here can shed some light on my situation.

Symptoms:
Car will not start after sitting overnight and especially cold mornings. Car will crank without issue but wont start. After about 10 times of trying finally it will fire up and will be fine the rest of the day.:dunno: I find the problem is much worse on cold mornings, for example this morning it was about -5c and after about 20mins of trying she just would not start.

There are no codes/check engine, it is a 2006 X5 4.8is.

Here is what has been done so far:

Replaced Fuel Pump Relay
Brand New Battery (Dealer Installed)
Fuel Pump
Spark/Ignition tests ok



When the car is acting up and not starting, we had no pressure reading at the rail this is what lead me to believe it was the pump.

Next steps, I will do some further pressure testing (leak down etc.)

Other possible culprits I can think of...fuel filter (regulator could be bad I guess???), crank sensor (but not sure if that makes sense as this only happens on cold start), Ignition switch?? I also thought of leaky injector, but there is no smell and when it acts up I have tried flooring the gas to open up and shut injectors but still no change.

All recommendations and suggestions would be greatly appreciated! We are coming into the colder months here and need this to get resolved. Keep in mind this only happens on cold start in the mornings, once it starts it can be turned off and on without issues.

Thanks!!:thumbup:

Anyone???:dunno:

Get a can of starting fluid. If the engine does not start, a 2 second shot of starting fluid will cause the engine to start and either die quickly which means there is no fuel or the engine will start with the help of starting fluid.

This way you can try to identify a fuel related problem.

Extended crank time on an X5. Check out this video. Spoiler alert, it could be a Crank Position Sensor.

https://www.youtube.com/watch?v=S1EmtwJh2o8

If you find the video helpfull I hope you subscribe to Ivan Youtube Channel.

So here is an update..

We are seeing spark, but zero pressure at rail. Upon further investigation we found that fuel pump does not appear to be priming or turning on when key is in "on" position. Checked fuel pump relay again and fuse and we are seeing power there and relay appears to be switching ok.

On spec I changed out ignition switch but still no change. Out next step would be to try to change out crank sensor, but I just don't want to be changing out parts just because. My mechanic also scanned multiple times and not seeing any error codes, we also re synced EWS and DME but it did not seem to help.

My question is, is there a "main" relay or ignition relay somewhere in the dept under the hood we can try? Would the CPS still be an issue if we have spark? Anything else we can try??


Thanks!

Doubt the crank sensor is a problem. Fuel pump priming does not require a crank sensor signal input. You have spark, so this kind of means the crank sensor should be working, however, some engines can fail over to the intake cam sensor input to use as a trigger for spark.

You have a fuel problem/electrical if no fuel pressure is at the rail.

Either the fuel pump dead, the fuel pump relay is bad or there is some other electrical related problem.

I would bypass the fuel pump relay and see if you can power up the pump with a separate power source.

Most likely your fuel pump is dead, but on your first post you said that you already changed the fuel pump. Did you buy a new fuel pump or a use fuel pump? You have current to the pump but the pump is not coming on you have a dead fuel pump. Hopefully you didn't buy a Wing Wang fuel pump from eBay or Amazon. People should stop buying cheap crap off of eBay and Amazon. If you can't afford to buy decent parts you can't afford to be driving a BMW.

Thanks guys, I agree that most likely it is not the CPS based on my symptoms. My fuel pump that I just put in a few days ago was new OEM, i don't use any aftermarket parts on my cars.

As mentioned before new fuel pump relay, even tried using another one with the same symptoms. What I forgot to mention, when we hook it up to scanner, we can initialize the fuel pump (here it prime) and when doing so we can also here the relay switch at the same time and see pressure. We just can't get the same results when turning the ignition on.

I am sure the pump itself is fine because when we turn it on via the scanner tool we here it prime and have pressure (+/- 50psi).

You can have a bad ignition switch.

Swapped out ignition switch yesterday, no change.