Fuel Pump?

Hi

just got my m535.

dont know much about mechanics but thought i'd try to fix it.

this may seem like a silly question.

Should i hear the fuel pump prime like on other cars when i turn the key?

also live in the UK. where is the best place to get parts online?

Originally Posted by complex_sk

Hi

just got my m535.

dont know much about mechanics but thought i'd try to fix it.

this may seem like a silly question.

Should i hear the fuel pump prime like on other cars when i turn the key?

also live in the UK. where is the best place to get parts online?

I honestly can't hear it in mine. There are two pumps though, one in the tank and one under the car. I have heard people complain about some aftermarket pumps being noisy. What is the problem you're tryong to fix? There's alot of sponsor sites that sell online and I'm sure some ship to the UK, but it maybe better to search the threads or start a new one in the General Discussions area.

The car won't start. It tries to turn over but I get nothing. Can't hear the fuel pump at all so wondered if that might be a place to start.

If you suspect the pump check the fuse for it first. I think it's fuse #1 (in the fusebox under the hood). The electrical connections can deteriorate on these older cars, check those, especially on the fuel pump in the gas tank. There's an access cover in the trunk under the mat. Three phillips screws. Are you sure you're getting spark?

Also are you getting spark? Have you tried puling the main relay and the fule pump relay. These relays are the ones on the left side of the fuse box and they are the first 2 they have a bad habit of going bad and they will cause the car to not run. You can switch out the horn relay for the fuel relay and see if that is the problem.

andy

You were right. No spark have tryed another coil no luck. Motronic ecu. Suspecting that. Could it be anything else?

Could be a crankshaft position sensor, bad rotor in the distributor cap, ignition switch, the wiring, etc? Check to see if you have 12 volts at the coil and check the battery connections.

Excellent will look into all that. But have to over come my latest bloody problem. Key won't open car anymore. No movement at all. Is it easy to open these with a coat hanger?

Don't know, haven't tried. Have you tried the other door? Don't you have any other keys? Maybe your Dealer can cut you a new one (if you bring him the proper ownership/registration documents)?

Finally got in driver door won't open. I'll sort that evenually.
As for the not starting. Am I right in thinking the euro spec car does not have a check engine lamp? If so can you get codes from the car without a reader.

I'm not aware of anyway to read the codes on these cars. Anybody? I know on alot of older American cars you could read a stored code by getting the check engine light to flash a certain sequence. I've looked in the Bentley manual and it doesn't have anything to say on the matter.

Have you tried cleaning up all of the fuses? Also have you tried looking at the two relays, the main and the fuel? As to codes, I have not heard about them and I have had 3 528e.

Andy

Main relay seems to be bad. Is there a way to hard wire the circuit without frying things. To see if it is definately that?

Originally Posted by complex_sk

Main relay seems to be bad. Is there a way to hard wire the circuit without frying things. To see if it is definately that?

There might be, but the Bentley and Haynes manuals don't have anything. You could experiment, but it could be risky.

I would suggest just buy one, they do not cost that much, do not hard wire it.

Andy

right seem to getting somewhere. took the main relay apart cleaned it up is working now. have tested all other relays and have power to the coil. still dont seem to have a spark. have removed the sensors and cleaned them up so will try that tomorrow.

anything else?

Originally Posted by complex_sk

right seem to getting somewhere. took the main relay apart cleaned it up is working now. have tested all other relays and have power to the coil. still dont seem to have a spark. have removed the sensors and cleaned them up so will try that tomorrow.

anything else?

Have you checked the distributor cap and rotor? What about the wire from the coil to the cap? That can deteriorate from corrosion sometimes and cause a starting problem. Check the ends in both the coil and the cap.

I have not checked the distributor yet. Have just had a thought? The ecu is hanging, has been removed from the mounts. Does it need to be grounded?

Originally Posted by complex_sk

I have not checked the distributor yet. Have just had a thought? The ecu is hanging, has been removed from the mounts. Does it need to be grounded?

I would think so. Worth a try, and hanging might put a strain on one of the connectors possibly affecting its performance.

Originally Posted by complex_sk

Hi

just got my m535.

dont know much about mechanics but thought i'd try to fix it.

this may seem like a silly question.

Should i hear the fuel pump prime like on other cars when i turn the key?

also live in the UK. where is the best place to get parts online?

I never hear mine. A great resource is pelicanparts.com

the fuel pump has a delay it wont turn on till the car is cranking over and trying to start it wont turn on with no spark

I am not sure if you are saying the car is not getting spark? Or you are just not happy because the car is delaying? I am going to guess that you have a slow fuel pressure leak, which is causing the fuel lines to loose pressure, which is why your car is not starting up right away. I have this problem and I have never been able to track it down so I just crack for 15 secs until the pressure builds up and the car turns over.

Andy

Originally Posted by south26

I am not sure if you are saying the car is not getting spark? Or you are just not happy because the car is delaying? I am going to guess that you have a slow fuel pressure leak, which is causing the fuel lines to loose pressure, which is why your car is not starting up right away. I have this problem and I have never been able to track it down so I just crack for 15 secs until the pressure builds up and the car turns over.

Andy

You might have a bad fuel pressure regulator.