Non starter

[Gavank]

Hi,
First post on the forum and could with a bit of help with a Z3 2.0i
Had to lay up during covid and have a fail to start.
So far.
Drained all the old fuel out and changed the fuel filter.
New plugs
Had a lumpy idle on and off prior to laying up so changed the throttle control valve and intake hoses at the same time.
Does run lumpy for a short time pumping accellerator pedal then cuts out.
Was ok when I laid it up.
Suspect fuel supply problem/pump or relay.
Any ideas beyond this would be appreciated.
Only done 70k.

 

[Robert Hill]

welcome from alloa scotland

 

[t-tony]

Pumping the accelerator is a red herring will make no difference as there is no throttle pump like on a carburettor engined car. Try getting a can of carburettor cleaner and get someone to crank the motor while you spray the cleaner into the inlet behind the air filter. Check for big splits in the intake bellows too. Are you anywhere close to me (Lincoln area?)

Tony.

 

[Gavank]

Hi
North Wales near Llangollen.
I'm away at the moment.
Plan on checking fuel to rail when I get home.
Mine is a 2.0i
Would you know if the pump relay is in the engine bay or behind the glove box.
I suspect the fuel pump is not primong.
On the 2.0 there from memory a drum like canister on the left that makes a sound on switch on.
Is this a second pump/priming pump?
The one in the tank I'll need to check.

 

[t-tony]

If you try the carb cleaner trick and it readily fires it does point to the lack of fuel. I thought the fuel pump relay was in the box under the bonnet near to the bulkhead. Having said that it is 8 or 9 years since I sold my 2.0 Z3.
Have a look at this,

View: https://youtu.be/hKpIhjNyvTM


Tony.

 

[Andyboy]

Is this the silver one with a hardtop bought from near Rhyl a year or so ago? It had a bad throttle body iirc.

 

[colb]

The round item in the engine bay that makes a noise on a cold start is the secondary air pump fitted for emmission control, it only runs for a few moments from a cold start and allows extra air into the exhaust to lessen the emmissions. It can be removed and a blanking plate fitted, @t-tony makes these if you want to delete yours. Here in the UK removal will not affect anything, the electrical connector can be left tied up out of the way. As to your non start issue, has the fuel filter ever been changed, often cars are found to have trhe original still in place, never changed when serviced by BMW in the early life of the car. Might be prudent to fit a new one if you dont know the history, it could be blocked and the source of fuel starvation other than the pump in the tank going bad.

 

[t-tony]

A valid point re the filter Col. I changed one for a member a few years ago after it dried out I cut it open and it was packed with crud.

Tony.

 

[Gavank]

The round item in the engine bay that makes a noise on a cold start is the secondary air pump fitted for emmission control, it only runs for a few moments from a cold start and allows extra air into the exhaust to lessen the emmissions. It can be removed and a blanking plate fitted, @t-tony makes these if you want to delete yours. Here in the UK removal will not affect anything, the electrical connector can be left tied up out of the way. As to your non start issue, has the fuel filter ever been changed, often cars are found to have trhe original still in place, never changed when serviced by BMW in the early life of the car. Might be prudent to fit a new one if you dont know the history, it could be blocked and the source of fuel starvation other than the pump in the tank going bad.

Hi
Thanks for your advice.
I changed the filter when I first got the car about six years ago. Put another new one in after I drained the bad /sour fuel out this time. Had half a tank in ,standing for three years so thought it best to change again.,

A valid point re the filter Col. I changed one for a member a few years ago after it dried out I cut it open and it was packed with crud.

Tony.

but no change to the non start up issue.
I'll check for fuel to the rail.
Initially thought it might be gummed up injectors but lets see how the pump is.
Cheers
Dave.

 

[Gavank]

Is this the silver one with a hardtop bought from near Rhyl a year or so ago? It had a bad throttle body iirc.

Hi,
No.
Bought this 6 years ago. Only done 10k in it.

 

[Gavank]

If you try the carb cleaner trick and it readily fires it does point to the lack of fuel. I thought the fuel pump relay was in the box under the bonnet near to the bulkhead. Having said that it is 8 or 9 years since I sold my 2.0 Z3.
Have a look at this,

View: https://youtu.be/hKpIhjNyvTM


Tony.

Ok Tony.
When I get home I'll check the relay.
It's the green one as far as I can tell. I've ordered a spare just in case.

 

[Gavank]

I spoke to a Garage that I use for MOT. He said check the fuel pump. Quote.Hit it with a rubber mallet. It might be a stuck diaphram.
Does that make any sense??

 

[colb]

Giving cmponants a wack sometimes works, starter motors usually respond to a wack if they are stuck but probably a sign its on its way out had that with mine on the Z4, replaced it which solved the issue. Now to use the same treatment on the fuel pump its going to be difficult to get at it as its under the firewall carpet behind the passenger seat backrest. Might be doable if you give the actual fuel tank a wack with a rubber mallet from under the car if its stuck maybe it will jolt it into working if it is indeed the pump at fault. Pressure test at the fuel rail might be an option if you can connect a guage and see if there is any pressure, if the pumps at fault you wont see much of a reading.

 

[Shelly]

 

[Gavank]

Giving cmponants a wack sometimes works, starter motors usually respond to a wack if they are stuck but probably a sign its on its way out had that with mine on the Z4, replaced it which solved the issue. Now to use the same treatment on the fuel pump its going to be difficult to get at it as its under the firewall carpet behind the passenger seat backrest. Might be doable if you give the actual fuel tank a wack with a rubber mallet from under the car if its stuck maybe it will jolt it into working if it is indeed the pump at fault. Pressure test at the fuel rail might be an option if you can connect a guage and see if there is any pressure, if the pumps at fault you wont see much of a reading.

Hi
I might have a connector to go to the rail.
I have a compression tester I've used in the past to check for cylinder compression.
Cheers
Dave.

 

[t-tony]

A compression tester won’t be any use as it is used to measure gas pressure. For fuel pressure you need a gauge for liquid pressure.

Tony.

 

[Gavank]

1999 Z3 2.0i
70k

Acomression tester won’t be any use as it is used to measure gas pressure. For fuel pressure you need a gauge for liquid pressure.

Tony.

Hi,
If I just use a rag or a jar to catch the fuel would that show enough to decide if the pump is working or not.
A failed pump would give nothing would that be right?

 

[t-tony]

It would tell if the pump is doing anything but would be better if you put a piece of tube off the outlet into a bottle or other container. A clear 2 ltr pop bottle would be ideal.

Tony.

 

[Gavank]

Ok
I've the fuse and relay to check and I'll go from there.
I'm away at the moment so don't have it's vin number. I've struggled to find the pump part number for the 2.0i. All coming up for the 1.9