M60 won't start

[dt8068]

Today I drove 1000 miles back to college from PA to florida, the car ran perfect the entire drive and it averaged 23 mpg. Well, about an hour after I arrived I went to start up the car again and it would crank but it showed no intention of firing up.

I figured it might not be getting fuel, so I had someone put the key in position 2 and also try to start the car to listen if the pump made any noise, and it didn't make a damn sound. From what I remember I used to easily hear the fuel pump from inside the car when putting the key in position 2.

Also, would a bad Crank position sensor cause the no start and if so how do I tell if its bad.

and finally, where is the fuel pump relay and the main relay and how do I find out if they are causing the fuel pump to not run, or if the pump itself is dead.

I'm trying to figure out all the things that might keep the engine from firing up, any help is appreciated.

oh, and the mileage on the car is 186,000 and I don't know if the pump is original. sorry for the long post.

[markus]

you can jump the 2 pins and see if the car is getting power at the the pump. but id first check and see if the car is getting power at the connector at the pump. you can use a test light for this. im not sure where the main and fuel pump relays are. on my E30 they were right on the drviers side under the hood.

[bbig119]

I'm going through the same sort of problem, only my car starts up but stalls outs, and had a hard time keeping idle. I just did some of the testing you are looking to do and its pointing to a slowly dying pump on my car. The relay you're looking for is in the box on the passenger side where the DME is. Its buried underneath a bunch of other wire connectors and you'll have to pull up the plastic rack that they're all connected to in order to get at the relay. In my car it was blue and of the three relays, it was closest to the engine, making it the toughest to get at. Its not difficult to get to, but you may have to dissconnect some wires to get at it. Jump connections for pins 30 and 87. The pump should run as long as the battery is hooked up.

If you do this you should also test power to the pump. If the car isn't starting, chances are testing pressure probably isn't needed. But if the pump runs when you bypass it, you should consider putting together a gauge and tapping into the fuel lines to test pressure.

Have you changed your fuel filters? It won't help if you have a dead pump, but do this if/when you change the pump.

I don't know anything about the crank position sensor except that its somewhere lower on my list of possible causes for my problem.

Hope this helps,

Bryan

[brosher]

In addition to the relay check the fuse for the fuel pump. Also, do you have gas? ;)

[dt8068]

ok, I tested for power at the connector going to the fuel pump with an LED light and it only lit up when the wires were put in pins 3 and 4. there is five pins at the connector and this test was done with the key in position 2. so i assume the fuel pump is getting power but like i said before it doesn't run with the key in position 2, or when trying to start the car.

So, after that I took out the fuel relay and jumped pins 30 and 87 with a wire and the fuel pump clearly turned on and I could hear a buzz in the engine bay.

does this mean that the fuel relay is the cause of my no start situation?

so i went and bought a fuel relay for $10 (waiting for it to come in), and I took the little blue cover off the old relay and it looks perfect inside, so could it be the relay or is there something else that would keep the pump from running?

[bbig119]

I seem to remember the Bentley saying that pin 4 is +12V and pin 5 is ground. You could also test fuel pressure.

[dt8068]

with everything connected except for the fuel relay removed, I jumped pins 30 and 87 (which made the fuel pump run) and tried to start the car but it just cranked and cranked. Is it even possible that the car would start this way, as in by running the pump by jumping the pins?

Also I have nothing to check for fuel pressure so I started to undo the clamp for the fuel out hose from the top of the metal fuel pump cover thing and fuel started to squirt out before I even removed the hose, so I assume the pump is working and there is pressure.

could it be possible that one of the two fusible links under the rear seat would keep the car from starting, and where exactly are each of them and how do i tell if they are bad.

I really need to get the car running so any help is greatly appreciated.

[dt8068]

anybody?

I also forgot to add that after I drove from PA to FL I had the car off for maybe 20 minutes as I unloaded stuff, then I went back out to go put more gas in it. When starting it took about 10-12 cranks which it has never done before even when cold.

After driving to the gas station which is less than a half mile away, I filled it up and when I went to start it after filling it took probably 20 cranks. I drove it back to the parking space and about an hour later I went to start it and it just cranked continuosly.

[TC535i]

I had ALL that on my 318... cranking, fuel pressure, spark...

Turned out something in the main relay was bad, and it wasn't opening the injectors. So even tho I had fuel as far as I could tell... I didn't, in the cylinder.

[dt8068]

yea, but would it make sense that its the main relay when the last two times it started IT DID fire up but it took forever to turn over (which i think might have something to do with the reason its not running). I would think the main relay would just all together die and one day it would just refuse to start. Or is it possible that the main relay slowly dies hence the last two very long starts which it has never done before in the 18 months I have had the car.

If it is the main relay is there anyway to test it aside from buying a new one?

[TC535i]

Yup, mine had starting issues too. Nobody around you can grab a relay from? Check the relay pattern, it may be a standard style relay... take it out and compare it to others at your local pep boys.

[632 Regal]

take the realy apart and see if its sticking or burned or something

[dt8068]

I took out the main relay and took it apart and the inside looks perfect, and I put a battery up to it and it operated perfectly (no sticking).

so what should I look at next?

Like I asked before, can one of the fusible links under the rear seat be causing this and exactly where are they and how do I find out if they are bad?

[Tiger]

I would say crank position sensor is bad. Can you pull any check engine code with the stomp test?

[Johntee540]

while we are on the topic of sensors.. How about the Cam Position sensor? Wouldn't that also feed the ECU in terms of when to fire the injectors? - JT

[dt8068]

ok, so after replacing the main and fuel relay the car still just cranks wiithout starting, so today I'm going to pull the spark plugs to check for spark and fuel. My question is, if the crank or cam sensor is bad will it allow spark and fuel to the plugs and injectors respectively?

another thing I don't understand is when jumping the fuel relay (30 and 87) the fuel pump ran, but with a new fuel relay the pump still won't run when the key is in position 2 or when cranking.

also if the spark plugs are getting spark is it possible that they are still bad and would prevent starting? although this doesn't make sense because the car just got 23 mpg going from philly to melbourne FL in 13.5 hours.

[dt8068]

anybody?

[Spasso]

You can waste time and money for weeks chasing a gremlin like this or you can bite the bullet and have the codes pulled with the correct equipment and let the car tell you what is wrong.

Sometimes the codes aren't always correct but at least it gives you a point to start from.

A good independant German shop should have the proper code reader for your car.

[TC535i]

Put a screwdriver on the fuel rail and the other end to your ear... have someone crank and see if you can hear the injectors clicking.

[BillionPa]

check fuel pressure, check spark.

if you have fuel pressure, and the sparks are rotating through all 8 plugs, i have no idea.

[TC535i]

check fuel pressure, check spark.

if you have fuel pressure, and the sparks are rotating through all 8 plugs, i have no idea.
Even if you have fuel pressure... without the injectors opening, it won't run.

[BillionPa]

indeed, although on an M60, fuel pumps tend to be the #1 culprit.

[dt8068]

first of all there are NO codes via stomp test that is why I'm chasing every possible problem.

I pulled the plugs and they were bone dry so the injectors are clearly not opening and the plugs didn't get spark. On the other hand I started to loosen the fuel hose where it connects to the fuel rail and there is definately fuel pressure going to the injectors.

This leads me to believe the problem is either crank or cam sensor. I imagine that either bad sensor (crank or cam) will not open injectors or give spark, correct?

So my question how do I test for a bad crank or cam sensor?

Sorry for being such a pain but I'm trying to solve this without taking it to the dealer, and there are no BMW specialists in the area. and I'm in no hurry to get the car running.

[Tiger]

On BMW it is almost always the crank sensor... just change it.

[karmann]

mine did the same thing hopfuly your luckier than I am...I changed the cam and crank sensor 2x ,still when I plug it into a comp get crank sensor code
and its not reading any thing ,even if plugged bak in and motor running...its pretty easy to unplug the crank sensor on mine just allittle tight to reach but it starts after turnig over a few times never more than 3 seconds...I usualy have to warm the car up b4 plugging the crank sensor bak in ..but no one has been able to figure this one out not even the dealer...Hope it goez better for you ...doez sound like a cps though..

[dt8068]

I'm waiting for a crank sensor from BMA, the old one I pulled out had a resistance of 350,000 ohms between pins 1 and 2. Isn't it supposed to be like 500 to 550 ohms?, so yea I have no idea whats up with that 350,000 ohm reading.