HAD TO BE ON THE EVE OF CHRISTMAS!!

[bmania]

MERRY CHRISTMAS TO ALL FIRST OF ALL.

RIGHT, I WAS DRIVING THE CAR ALL DAY YESTERDAY WITH NO PROBLEMS. TODAY MORNING I WENT TO START THE CAR TO GO FOR SOME LAST MINUTE CHRISTMAS SHOPPING AND GUESS WHAT?

THE CAR TURNS OVER BUT IT DOESNT START. I FIRST THOUGHT THAT IT MIGHT BE BECAUSE OF THE COLD BUT IT WASN'T COS I TRIED A GOOD FEW TIMES. I QUICKLY TOOK OUT MY TESTERS AND CHECKED WHETHER THERE WAS CURRENT IN THE IGNITION COIL. POSITIVE AND NEGATIVE BOTH TEND TO HAVE CURRENT.

BUT THE PROBLEM IS THAT THERE IS NO CURRENT GOING TO THE SPARK PLUGS TO FIRE UP THE CAR. SO THEN I TRIED CHECKING IF THERE IS CURRENT GOING INTO THE DISTRIBUTOR CAP. I TOOK OF THE IGNITION LEAD THAT CONNECTS ON THE DISTRIBUTOR CAP FROM ON TOP OF THE COIL, HELD IT NEXT TO THE BODY OF THE CAR AND I SEE A LITTLE SPARK COMING ON AND OFF EVERYTIME I SWITCH THE IGNITION ON AND OFF, BUT WHEN THE CAR IS TURNING OVER THE SPARKS DISAPPEAR.

I ALREADY TRIED REPLACING THE IGNITION COIL (2ND HAND) AND THIS WAS UNSUCCESSFUL. I DON'T KNOW WHAT ELSE I SHOULD DO SO I CAME FOR THE E30 GENIUS'S ADVICE. I AM SERIOUSLY LOST AND PISSED AS I NEED TO GO VISIT FAMILY FOR CHRISTMAS TOMORROW.

SOMEONE HELP AS THIS PROBLEM MAY LEAD TO A BAD CHRISTMAS AND A DIORCE.......LOL

HELP MUCH APPRECCIATED THANKS IN ADVANCE

[tomislav]

take the dizzy cap off and check inside it, my 325 started one day and not the next because this was worn (and the rotor arm of course)

[bmania]

I TOOK THE DIZZY CAP OFF AND THE ROTOR ARM OFF AND CLEANED IT AND WAS'NT WORN AT ALL. ALSO CLEANED THE CONNECTIONS ON THEM FOR THE HT LEADS. I HAVE A CLIFFORD CONCEPT 300. COULD IT HAV ANYTHING TO DO WITH THE IMMOBILISER AS I IHAD ALARM PROBLEMS BEFORE BUT NEVER THIS SORT?

ALSO, SOME ONE TOLD ME IT COULD BE THE ECU UNIT OR THE CRANK SHAFT POSITION SENSOR? BUT THIS PROBLEM CAME ALL OF A SUDDEN. IF ANY OF THESE WERE THE PROBLEMS WOULD IT AFFECT THE CURRENT GOING TO THE SPARK PLUGS?

[stonesie]

The Crank Position Sensor would cause this because the ECU wouldnt know the engine was turning, so it wouldnt trigger the coil.

First i would check the wireing connector under the inlet manifold and the wireing around it for damage and corrosion.


And talking of takeing CAP's off......

[tomislav]

stonesie is right. If the crank sensors packed up it will just not start oone day

[bmania]

is this all a process of elimination or is there a way i can find out for sure what the problem is? because christmas has made me a lil skint.

[davidt]

There are some visual checks you can do, make sure the pulse sensor plug is connected, check the fuel pump relay is working, have a look for air leaks in the intake system.

[bmania]

ok the AA jus came down, they checked the currents at the spark plugs, fuel injectors and few other places and they reckon it is the crankshaft sensor. the crankshaft sensor is located next to the alternator, anyone know how to replace this, as i dont know where the other end of it is connected. all i can see is the sensor connected to the wiring loom? it is a 1987 325i manual convertible!!

[tomislav]

If i remember rightly its a 5mm allen key to get the bolt out that secures it but i don't know where the other end is. I know it seems to run up towards the dizzy cap but after that i'm not sure. Best thing to do is take it out then try to trace it back by wiggling it around. Not like you can really break anything... hopefully! Best of luck mate

[bmania]

ahhhhh these electrical problems are the worst. i know im being a pain but is there a way you can test the crankshaft sensor to see if it is knackered. the other end of it seems too go in the wiring loom under the port where the reset tool goes into, then goes into another wiring loom and then im lost.

[davidt]

The connector is just below the diagnostic plug, the left hand one on a 325i

[bmania]

one part of the cps is connected next to the alternator near the crank, and the other is under the diagnostic plug?

[davidt]

Can only quote from the manual, Check the resistance at terminals 1 and 2 on the connector. if the resistance is not approximately 540+-54 ohms the sensor is faulty.

[Brianmoooore]

The first thing to check is if the fuel pump runs when you crank the engine. If it does, the problem is probably not the CPS.
If there is no fuel pump activity or sparks when the engine is cranked, either the engine ECU isn't being powered up or the CPS is probably faulty - assuming that a faulty alarm isn't sticking its oar in!
Since there is power at the coil but no sparks, and the engine cranks, you can probably assume that it's not an alarm fault.
Second thing to check is that the main ECU relay (white one) clicks when the ignition is switched on.
This relay is under a cover on the inner wing near the air filter. (You haven't said what engine, but I assume it's a six pot by the location of the diagnostic connector).

[bmania]

youre right, it is a 6 pot engine 325i 1987. there is no fuel pump activity and the current doesnt go to the spark plugs thats why i am assuming it is not the distributor cap. The ignition coil has got power in it though. The worker of AA put some kind of tool in the fuel injectors plugs and said its lacking some sort of pulse.

are you talking about the 2 relays under the black cover near the air filter? if you are then i checked them but none of them are white? one is blue 12v 30amp and the other is black also 12v 30amp but is a bit smaller in size. i replaced the blue one with another still no luck.

i dont really get cps thing though. when i plugged it out? i dint see any connectors on it nor can i find the other end to it so i dont know how to check whether it is knackered.

mr moore help me please...

[Brianmoooore]

The ECU main relay is one of the two under the cover - probably the black one. Definitely, if it has five pins.
The lead from the CPS runs around the front of the engine, in a cover behind the fan/water pump pulley, and then is one of two similar plugs and sockets fitted to the metal bracket under the diagnostic connector at the top front of the engine on the inlet side.

[bmania]

thankyou very much mr moore. i will try my luck early 2moro morning. if no luck i will be back to bother you later on this week. lol

[bmania]

and thankyou everyone else that helped me on CHRISTMAS EVE, but i have a feeling i will be back as me and electrics dont really get along

[jacko]

I sometimes get this problem on my Omega , After giving the knock sensor a couple of taps she fires up OK for a couple of weeks.

[Brianmoooore]

After giving the knock sensor a couple of taps she fires up OK .

Won't work with an E30, since no E30 had a knock sensor as standard.

[murran]

sounds like crank sens to me. had a running fault on mine, so replaced it as an elimination proc. turned out to be a failing icv.
but power to the coil but no spark.......... crank sens.
i have a new one here from ecp. cost £35 your welcome to it for £20 posted. pm me! other wise............ euro car parts open xmas day??

[bmania]

thanks for theoffer, i will 100% let you know by thursday. you lot have been very helpful

[bmania]

found the exact symptoms of the car which are:

No fuel injector switching and no sparks.

suspisions are:

Crank position sensor?
ECU unit?
Faulty relays? which ones apart from ecu?

What is best to replace 1st?

[Brianmoooore]

Second thing to check is that the main ECU relay (white one) clicks when the ignition is switched on.
This relay is under a cover on the inner wing near the air filter.

This relay switches power on the red wire to the red/white and red/blue wires. It can be bypassed by using wire to link together pins 30, 87 and 87a of its base.
Chances are that the CPS is the problem. Disconnect it under the diagnostic connector and measure the resistance across the two pins nearest the lead. Should be about 540 ohms, and stay constant if you wriggle the wire, especially near the sensor.

[bmania]

thanks so much for your help brian, i think i have the sensor that has no 5mm bolt on it and has the 3 wires on the othe side? so shud i measure the resistance across the yellow and black wire? and is this connection also under the diagnostic plug?

and the red, red/white and red/blue wires are the ones under the ecu relay near the inner wing like you said yesterday? i will make sure to check them tomorrow after your reply and advice. i hate it when it gets dark so early.

[Brianmoooore]

You've found the sensor, and are correct about the relay wires.
There are three pins in the CPS plug. One of them is just the earth connection for the screen on the cable, and the other two are connected to the coil. When you have the plug disconnected and look straight into the pins, the two nearest the lead are the two to measure across.

[bmania]

hello mr byan moore? i carried out what you adviced me to do today. the ecu replay port did not need to be bypassed as the relay was clicking when the ignition was turned on and off.

i carried out the CPS checks but i am not sure if i done it right. i left the sensor in its position and used the mini multimeter to check the resistance by using one point touching the yellow and the other point to the black that is wrapped round the other two wires and i was getting a reading that was going up and down rapidly from as high as 900+ to -100. when i inserted one point of the multimeter into the yellow and the other point into the other black wire i got a reading of 0 while the ignition was on and off. was this correct?

also from what i can see is that the yellow black and other black wire seem to only connect to the diagnostic plug? how is this connected to the ECU.

[bmania]

im sorry to ask so many questions but also if i was to replace the CPS do i just pull out the three wires from the diagnostc and plug the new three wires in. is it a simple job or will it need an auto electrician. i only ask these because any mechanic i call is not farmiliar with the E30's especially the electrics. will a diagnostic machine help to identify the problem to determine whether it is the ECU or CPS.

I noticed just today that there are couple of slits in the CPS leads near the alternator. it doesnt seemed to have cut through the wires completely but the rubbering aroung the wires have been slit so have a little bit of the wires. i do not know whether this was there prior to the problem or not.

thankyou very much in advance.

[bubbazenetti]

I had a concept 40 on my 89 325i with the same symptoms as yours, there was a dry joint at the battery terminal , I had to crimp a new conector onto it (it looked totally fine but wasnt) this sorted it.

I am sure you have looked at this already but the other thing to try ubless you are very certain it is the spark side of things, is the fule pump relay, always worth having one spare in the boot if its not that anyway.

John.

[bmania]

if it was the fuel pump relay this would not affect current going in to the spark plugs correct? so i doubt it could be the fuel pump relay? i swopped over the fuel pump relay with one in the fuse box just to test and it still dodnt fire up as long as the fuel pump relay is the one next to the ecu one on the inner wing.

could a dry joint of a battery terminal leads to the symptoms? fuel injectors not switching and no sparks?

[Brianmoooore]

If there is no fuel pump activity or sparks when the engine is cranked, either the engine ECU isn't being powered up or the CPS is probably faulty -

One of the two smaller red leads that come from the battery + terminal, (or the phantom battery + terminal, near the front battery tray, if the battery is in the boot), feeds power to the ECU, so, if there's a problem with this supply, then the ECU won't be powered up.
Use a 12 volt bulb 5 - 21W, NOT a meter, to check if there is a permanent 12 volts supply at the red wire on the main ECU relay.
To test the CPS, it must be unplugged from its socket on the bracket under the diagnostic connector, and its resistance measured by connecting a meter to the pins in the plug.
There are two similar plugs and sockets on this bracket, and if the wires from the one you're testing go to the diagnostic connector, then you have the wrong one.
The other connector is for a pulse sensor threaded on to number six plug lead, and the connections from this do go just to the diagnostic connector on early engines, but also to the ECU on later engines.

The clicking ECU relay only proves that the control circuit for it is working properly. It doesn't prove the relay is good!
You are quite right to discount the fuel pump relay at this stage.

[bmania]

i think i have been looking at the camshaft sensor all this time, this does just go to the diagnostic connector is that correct? and this does not have anything to do with the starting.

now i have to find the crankshaft sensor, the reason i thought that my camshaft sensor was my crank was because the man from the AA said so. this was my bad for listening to him an not researching it my self.

OK i will do this 1st thing tomorrow morning. it is right for me to discount the immobiliser at this stage as well?
and i will put a piece of wire on the red wire of the main ecu relay and touch this onto a 12v bulb?
and i will try to find where my sensor plugs onto tomorrow.

is there any pictures or diagrams i can find to see where both ends of my CPS fits onto.

[Brianmoooore]

and i will put a piece of wire on the red wire of the main ecu relay and touch this onto a 12v bulb?
.

Take a bulb with a single, central terminal on the bottom (e.g. 21W indicator/brake light/reverse light bulb) and a length of wire, stripped of 15mm at each end.
Hold one end of the wire onto the side of the bulb with your fingers each side, sit the bottom terminal of the bulb on a good earth (e.g. rear bonnet catch), and push the other end of the wire into the 30 terminal hole of the ECU relay's base (the one the red wire goes to).
Try the same thing on the + terminal of the ignition coil as well, with the ignition on.

[bmania]

ok will let you know tomorrow. thanks

[bmania]

thankyou everyone for the help especially brian, it was the CPS after all. if it helps anyone the later 1987 models cps plug is next to the starter motor. over here there are two plugs, the one with the grey plug is the cps and the one with the black is the speed sensor. the actual sensor itself in connected to the bellhouse.

i will be back after the weekend to get some info about steering rack and the master cylinder?