BMW 325i running then dying

Post Sun Nov 15, 2015 1:52 pm

I've got a 325i just bought guy said fuel pump is knackered so ordered one up I'm 90 per cent sure that is the problem.the car starts on the button but idles terrible and won't let you rev it at all then will cut out can't here the pump making any noise at all. Done a resistance test on the pump 27 ohms which would tell me knackered pump checked there is power there and that's fine. Got a genuine bmw one coming so take it that's plug and play also got fuel filter as well coming tue

Post Sun Nov 15, 2015 3:26 pm

cookster wrote:idles terrible and won't let you rev it at all then will cut out can't here the pump making any noise at all.

These aren't the usual symptoms of a duff fuel pump, but aren't impossible. A check on the fuel pressure with a £10 gauge kit from ebay would confirm or otherwise.
Fuel pump only runs when the crankshaft is turning, so you don't normally hear it because of engine noise.
Whether or not your new pump is plug and play depends on whether you have bought just the pump, or the pump and frame assembly.

Post Sun Nov 15, 2015 3:40 pm

Thanks for your reply the guy who I bought it off said the aa man done a fuel pressure test and checked and there was no pressure and even with back seats out and everything you can't hear nothing from the pump. The aa man said it was pump and I've got the whole assembly complete thanks Ben

Post Mon Nov 16, 2015 3:15 pm

Well got pump on and new filter and fired straight into life need a battery now but hopefully that's it all good running rich tho big time

Post Mon Nov 16, 2015 6:54 pm

Well now not starting

plugged diagnostic machine in came up coolant temp sensor would this make the car run rough and stink of fuel big time

Post Mon Nov 16, 2015 6:55 pm

Just basically starting then flooding itself to cut out

Post Mon Nov 16, 2015 7:13 pm

What age is the 325i? Don't take info. from diagnostic machines at face value.

Post Mon Nov 16, 2015 10:20 pm

87 bud well looking through forums and stuff seems like a common problem

Post Mon Nov 16, 2015 11:37 pm

'87 is the answer I didn't want to hear! That's the changeover year between pre and post facelift.
IF your car is post facelift there is a round plug and socket fixed to the black metalwork under the inlet manifold, where the injector loom plugs into the main engine loom. There is a water trap under the rubber boot of the lower half of this connector which results in corrosion of the wires inside. The thinnest of these wires is the wiring to the coolant temp. sensor, and if this rots through, you get the symptoms you describe.

Post Tue Nov 17, 2015 10:09 am

i think mind is the facelift model but i shall go and have a look now.the plugs are totally black and the idle control valve seems to be running constantly even without the key in it so have unplugged that for time being.thinking about maybe handing it over to specialist soon as i dont wanna spend lots of money on it.im in the reading area if anyone nos of anyone thanks guys

Post Tue Nov 17, 2015 10:58 am

Took off connector had lots of green stuff in cleaned it all out with electrical spray put it back in now even worse

Post Tue Nov 17, 2015 2:08 pm

It's under the rubber boot of the lower half that the worst of the damage occurs and electrical cleaner won't reconnect a severed wire.
The plug and socket wasn't fitted on the pre facelift models, and the easiest way to solve a bad case of the problem is to splice in wires to revert to this arrangement. You may have to strip back the damaged wires some distance to be able to find bright copper that can be soldered to, so you may end up needing two joints in each wire, with a new piece of wire between them.

Post Tue Nov 17, 2015 2:13 pm

ok i see well i may have disturbed some thing there when i took it off then ive literally just got our recover driver to take it to a specialist dont really have the time to be doing it as everything else is backing up now so ill let ya no what the outcome of it is thanks

Post Wed Nov 18, 2015 10:18 am

cookster wrote:ok i see well i may have disturbed some thing there when i took it off then ive literally just got our recover driver to take it to a specialist dont really have the time to be doing it as everything else is backing up now so ill let ya no what the outcome of it is thanks

right update the guy has looked at the car and this is a list of the things he wants to do remove clean adjust throttle housing reset switch check adjust valve clearances replaced fouled spark plugs re pin that dodgy muliplug and sort wiring out under the inlet he said no guarantee it will sort the issue but its a starting point 300 pound which for all that work i didnt think was to bad

Post Wed Nov 18, 2015 10:25 am

That lot should sort it, but you'd be about £250 better off and gain a whole lot of knowledge and skill if you did it yourself. Getting the injectors rebuilt (see our traders' forum) would be money well spent as well.

Post Wed Nov 18, 2015 3:20 pm

yea i would like to give ago myself but i just dont have the time i already have a mk1 escort that im rebuilding from scratch ive done all the pistons and head on that but only a 1700 crossflow nothing like the m20 engine.i will let you no what the outcome is thanks guys

Post Wed Nov 25, 2015 4:43 pm

Brianmoooore wrote:That lot should sort it, but you'd be about £250 better off and gain a whole lot of knowledge and skill if you did it yourself. Getting the injectors rebuilt (see our traders' forum) would be money well spent as well.

right so update the guy has done all that work and still no difference unfortunately he is now saying there is 2 bolts snapped off the inlet manifold and he wants to take that off to check the spray pattern of the injectors.saying that they could be like water pistols instead of a mist and then replace the 2 bolts that have snapped off aint said a price yet

Post Wed Nov 25, 2015 7:00 pm

Not too late to roll your sleeves up and get the tools out!
Measure the coolant temperature sensor resistance AT THE ECU PLUG with the engine stone cold and again at full working temperature (if you can get it to run that long.)

Post Thu Nov 26, 2015 3:47 pm

Relay

Post Thu Nov 26, 2015 3:50 pm

Fuel pump relay

Post Sun Nov 29, 2015 8:39 am

You can here the relay working and it's throwing in fuel massively so think that's all good

Post Sun Nov 29, 2015 11:57 am

Brianmoooore wrote:Measure the coolant temperature sensor resistance AT THE ECU PLUG with the engine stone cold and again at full working temperature (if you can get it to run that long.)

Will also posted this request near the start of the thread, and we still haven't seen the results.
Both Will and I diagnose on the results of tests, not indulge in wild guesswork. If you want our help to sort this, do the tests and post the results.

Post Fri Dec 04, 2015 10:30 am

Yes this is being done along with the injectors will let you no when all is hopefully ok

Post Sat Dec 05, 2015 2:34 pm

Brianmoooore wrote:Not too late to roll your sleeves up and get the tools out!
Measure the coolant temperature sensor resistance AT THE ECU PLUG with the engine stone cold and again at full working temperature (if you can get it to run that long.)

Well injectors done coolant temp sensor done still not running right the guy has now told me that previous owner has the wrong air flow sensor it's for a 320i the one that is on it.so now need to get 325i one that would cause rough running

Post Thu Dec 10, 2015 5:31 pm

Brianmoooore wrote:
Brianmoooore wrote:Measure the coolant temperature sensor resistance AT THE ECU PLUG with the engine stone cold and again at full working temperature (if you can get it to run that long.)
Will also posted this request near the start of the thread, and we still haven't seen the results.
Both Will and I diagnose on the results of tests, not indulge in wild guesswork. If you want our help to sort this, do the tests and post the results.

Right car is running but still a bit rich guy said he has done a check it'd defo the return is blocked on the tank coursing it to over fuel what is best way round this guys can take tank out no problem

Post Thu Dec 10, 2015 9:12 pm

Difficult to see how the return to the tank could be blocked, if the regulator has been declared OK.
On the 62 litre tank the fuel returns to the tank via a stub pipe low down on the front left, and is used to prime the internal syphon tube that transfers fuel from the LH side of the tank to the right.
Still haven't seen the coolant sensor test results.

Post Fri Dec 11, 2015 6:26 am

Coolant test has been done the guy who is a specialist changed the sensor cause I had it anyway and tested it all working fine.he took the fuel return off and put it into a separate tank and car ran lovely.looking at the Internet it's a common fault with these fuel return blocked increasing the pressure pushing more fuel in just wondered if there was a quick fix

Post Fri Dec 11, 2015 9:58 am

willnz wrote:Common fault? really?

Can you provide some internet references to this "common fault", since it's a new one on me!

Post Fri Dec 11, 2015 10:20 am

Oh really I just put in BMW e30 fuel return blocked and loads of stuff comes up most saying put a new tank in because the rust and bits and pieces blocks it up.some saying use a coat hanger to push through the tank and get a blower and acid wash the tank or new tank lots of stuff on the Internet

Post Sun Dec 13, 2015 8:09 pm

Brianmoooore wrote:
willnz wrote:Common fault? really?
Can you provide some internet references to this "common fault", since it's a new one on me!

Have you guys not heard of this then does anyone no of a quick fix or is it a new tank the fuel return is under a lot of pressure can't even squeeze the pipe stinks of fuel out the back of the car broke down today when I put fuel in it towed him home.just went to start it started fine ran poor until warm then ok bug still stinks of fuel

Post Sun Dec 13, 2015 8:29 pm

No, I've never heard of this, although I can see it's possible for rust to be drawn up from the LH side of the tank into the syphon tube. I would have thought it unlikely that the pipe would block, with the fuel flowing in continuously from the return line, even if the syphon action did fail.
However, if that's what's happened, the first thing I'd try is an air line on the tank stub pipe. If that fails, access to the inside of the tank to try and 'rod' the pipe with a filament of some kind, is only by the pump flange on the RH side and the identical hole for a level sender on the LH side, which is going to require someone with a very small hand.

Post Mon Dec 14, 2015 6:58 am

Yea it's the actual tank that is blocked pipe is fine I will give this ago see if I can unblock it

Post Fri Dec 18, 2015 6:55 pm

Brianmoooore wrote:No, I've never heard of this, although I can see it's possible for rust to be drawn up from the LH side of the tank into the syphon tube. I would have thought it unlikely that the pipe would block, with the fuel flowing in continuously from the return line, even if the syphon action did fail.
However, if that's what's happened, the first thing I'd try is an air line on the tank stub pipe. If that fails, access to the inside of the tank to try and 'rod' the pipe with a filament of some kind, is only by the pump flange on the RH side and the identical hole for a level sender on the LH side, which is going to require someone with a very small hand.

Right so changed the tank completely blocked put new tank in runs like a dream now which is good the idle control valve is constantly running tho even with engine off which drains battery if not disconnected over night always something with these