Car won't start - Electrical Fault - No spark or Fuel

[jlgrosvenor]

Threads relating to this one are available here (http://www.volvoforums.org.uk/showthread.php?t=53584) (flywheel sensor) and here (http://www.volvoforums.org.uk/showthread.php?p=414094) (relays). Keeping everything in this one thread makes it even more of a monster.


The car is a 440 1.8si
B18U engine - 1995
I have a Fenix 3B computer.

I have removed the engine from my car, stripped down and overhauled the head, new oil seals on the block and head, new clutch.

Upon refitting it started 1st time. Great I thought.
After about 1 minute of idling fine, it cut out. Topped up with fuel just to make sure. Connecting a spark plug to the main input for the distributor was giving no spark when earthed on the engine.
I fiddled about with the connection on the crank sensor, and it was sparking again. Connected the main lead back to the distributor, and the car started.

About another 1 minute later, the car cut out. Fiddled with the crank sensor - car working again.....

....and repeat.

Several times

I read that the hall sensors can get gunked up a bit, and that and cleaning them can ressolve the problem. I did this, and it seemed to be fine. I checked the resistance which was around 225 ohms.

Car was running for about 4 minutes after I plugged it back in, then it dies. Same problem with no spark again, so fiddled with the connection and it worked again immediately. This time, it idled for about 10 minutes and I gave it some revs to get hot enough for the radiator fan to come on. The temperature returned to normal and another minute or so idle until I turned the car off. False sense of security obtained!

I thought I would brave a run in the car. After 10 miles, and just after a round-about, you guessed it. The car cut out, which was a fortunate place to do so, because there was a lot of on-street parking available. This time, a simple fiddling of the connections did not help. I tried unplugging the crank sensor, and the other two similar style plugs that come out of the side of the ignition unit that the king distributor lead joined to it. I had almost given up hope, but the car eventually started. I then managed to do 20 miles over the rest of the day with no problems. Concerned about a possible temperature related issue (worn out crank sensor loosing ability to detect magnetic field at higher temperatures) I ran the rest of the distance with the windows down and heaters on full-hot.

I decided to stump up the cash for a new crank sensor. £22 for an identical Siemens unit. I replaced this last night, and the car started immediately, on the button (a rev or two of the engine). The car was running fine for about 3 minutes, and then died again. New crank sensor is 242 ohms.

The spark is no longer present from the king distributor lead. No amount of fiddling with the previously mentioned cables has had any affect. All other electrics in the car appear to be working fine.
The battery is at 12.5 volts. The alternator had a relatively new regulator a few weeks before the strip-down, but the car was running fine with this before work started.
Mechanically, when running, the engine sounds fantastic.
I have replaced the coolant temp sensor on the front of the head.
When I turn ignition to position III I can no longer hear the fuel pump. Disconnecting the fuel lines from the top of the engine and cranking the engine over does not deliver fuel.

Fault codes 1-1-3 and 1-3-2 were present with the LED check. Translation of the fault codes were open circuit in injector wiring and incorrect battery voltage.
After clearing the fault codes, after trying (and failing) to start the engine again, no more fault codes are present.

All (3?) earths on the chassis give 0 ohms resistance when measuring a point on the chassis and the other end of the cable.

Not managed to work out how to check the oil temp sensor, but this is unlikely related.

Coolant temperature sensor on head shows 3500 ohms. This is the same as the old sensor that was replaced (I checked this too).

Disconnecting knock sensor makes no difference.

All earths show 0 to 3 ohms, but this could be due to corrosion on the metal surface. The result should be low enough.

Ignition signal produces a constant LED when connected to earth and terminal B of plug II from the ignition module. The LED then flashes if the engine is cranked over - as it should. There is no change in polarity recorded on the LED tester.

Resistance between pin A and terminal 1 on the ignition module reads as 1 ohm. It should be zero. Might be my multimeter is only accurate to 1 ohm.

Ignition coil secondary windings (once removed from the front of the ignition module) read 6554 ohms between the pins 1 and 3 (connection for king HT lead). Specification is 4000, +/-1500 (typical) so this is 1054 ohms out of specifcation. Ignition coil primary winding read 1 ohm (ish). Should be 0.6 +/- 0.2 ohms.

As the coil is out of specification, I got another from the scrap yard. The new coil measures 5330 ohms between pins 1 & 3. Not sure if this is still getting a bit on the high side, and could be a sign that this coilpack is also shagged. If it were JUST the coilpack, should I still be getting fuel pump priming at ignition postion III? and if I remove the fuel feed line, should it still pump fuel when cranking over?

Applying 12 volts directly to the fuel pump causes the pump to run normally.

I checked the resistance between pins 2 and 3 (the middle two pins) on the brown four-pin air temp/fuel injector connection for the single-point injection (underneath the black cover that sits over the top of the engine). Specification is 1.2-1.6 ohms, I get 2 ohms, but cannot read fractions.
Pins 1 and 4 are for the air temp sensor and show 3100 ohms, with a specification of 2500 ohms +/-300. Is 300 ohms too high going to make a difference?

Took me ages to get the ECU connection out in the passenger footwell, under the side cover. That is because this is a lie from the Haynes book of lies. It is under the side panel in the drivers footwell. After putting everthing back in the passenger footwell, I eventually got to what I was after on the drivers side (ECU connection looks like a humungous SCART lead connection).

Because the symptoms are so much like the crank sensor (although it is still not firing up tonight at all) I though I would rule this out. Checking resistance between ECU cable pins 11 and 28 (from the B18U wiring diagram) should show the same resistance as the crank sensor if I have understood the diagram correctly. Oddly, the resistance was 232 ohms, and at the sensor (detailed above) it shows 242 ohms. Pretty close, and I am hoping this is because I can get a better connection with the multimeter on the ECU cable terminals.

Are there any other checks I can do with the terminals on the ECU connector? Can you advise of item, pins and result looking for?

I have eventually conducted the ignition coil power supply (terminals 1 & 2 on the front of the ignition control module with the coilpack removed) test using a 12V, 5W bulb. This does not give a flashing bulb when the started is turned over. I checked the bulb works before the test. I have also used the newer ignition control module to test that I got with the coilpack from the scrap yard yesterday.

Working backwards (now I have the benefit of an assistant for the afternoon) I can now test the power supply to the ignition control module. HBOL says this should be a minimum of 9.5V, but I am suspecting that it should be about 12V inline with the power supply. The voltmeter is connected between pin A on connector I and earth. I am only getting just over 1 volt when the started is turned over, which ties in with the fault code 1-3-2 mentioned above (incorrect battery voltage). The inadequate supply of voltage here would be one reason I am getting no spark from the coilpack. The 1 volt reading sounds remarkably similar to a problem discussed in another post I have read in which the ECU was a suspect.

HBOL says, if there is NO voltage, check the supply lines from the ignition switch to the ignition module. If the voltage is too low check the battery.

Well, I get low voltage, but the battery is fine. Despite all the engine turning over I have been doing, it is still reading 12.3 volts. A bit lower than ideal, but it should still be enough to generate a spark.

Two of the three relays under the dash do not seem to be working correctly. See this thread (http://www.volvoforums.org.uk/showthread.php?p=414094) for more details on the relay tests I have conducted, and their individual locations. It may be that the relay in the red plastic holder is for the fuel pump, and this one is OK.

[jlgrosvenor]

Copied over from my relay and fuel pump thread here (http://www.volvoforums.org.uk/showthread.php?t=59736)

Did you check the mass connection on top of the engine, on the engine hoist eye. Connect an amp meter on battery mass connection behind the battery and on the hoist eye. Should read no more than 0.5amp.


There shouldn't be any amps to measure during the hoisting, the battery was disconnected and out of the car.

The hoist was manually operated hydraulic.

[Paul240480]

A monster thread indeed! Good luck, hope you get it sorted soon. Had'nt realised how complicated it had become!

[B20F]

The diagnostic box has a selfcontrol function for several functions. Some of them are of intrest to your situation. It activates the components and at the same time the LED on the diagnostic box flashes with the same intervals.
Put the sensor in socket #2, ignition on
Push the button on the diagnostic box 3x within 1 second.
Now a cyclic start
1. injectors LED flashes (and injectors should click) at 13hz (13 times a second)
2. Fuel carbonfilter valve at 2hz
3. Airco clutch 1hz (even without an airco fitted!)
4. System relay 1hz
5.Idle controler B18U 13hz
6.main relay 1hz.
Came across this in the original Volvo manual. Never tried this myself, so no idea if this and how this will work. But may be of help in diagnosing your problem with the relais.
Good luck hunting!

[jlgrosvenor]

After much electrical testing, it turns out that there is something wrong with the feeds to (at least) one of the relays under the dash.

I replaced the two dodgy relays I had with ones from the scrap yard that I verified to be working out of the car with the help of a voltmeter and 12V battery. After replacing the relays, the car started 1st time, on the button. I am still reluctant to just ignorantly assume this was the cause of the real problem, and drive around until the same thing potentially happens again.

To find out which of the three is the fuel pump relay,I turned the ignition to position II with a relay removed from each space in turn and listened for the fuel pump running. As it turns out, it is the relay on the right (which actually has a white base).

According to HBOL, with the relay removed the pins in the socket should read:

i) Pin 30 should register 12 volts. It does on mine :thumbs_up:
ii) Terminal 86 should register 12 volts when ignition is switched on. It does on mine :thumbs_up:
iii) Terminal 85 should register 0 to 1 volt for three seconds when the ignition is switched on (the time the fuel pump buzzes for) and then change to 12 volts. Mine just registers 0 volts all the time :thumbs_down:
iv) Terminal 87 should register 12 volts for three seconds when the ignition is switched on and then change to approximately 1 volt. Mine just registers 0 volts all the time :thumbs_down:

So it looks like the connection or components on pins 85 and 87 are causing problems.
I have put in another ECU to see if that made any difference. It doesn't and I get the same results.

According to the HBOL wiring diagram, pin 87 goes through the EVAP system for B18FP engines (mine is B18U), connects to pin 2 on the injector wiring and also possibly to the ignition control module.

Pin 85 seems to connect straight to the 15amp rail, but it goes through a box on the diagram that is labelled x7, and crosses three other lines. You can see this on the picture I have added.

I think all the rails labelled in red supply power. I have labelled them as per HBOL.

12292

[jlgrosvenor]

Are there any kind souls out there who can help me, with a few minutes to spare and access to a voltmeter?

A test with a known running 400-series Volvo should help find out if the measurements on my car are correct.

If anyone is kind enough to help with this, the procedure is as follows:

i) Check that when the ignition is turned to position II, you can hear the pump prime for about 2 seconds. You will need to do this somewhere relatively quite. At the side of a busy road, you probably won't be able to hear it unless lying on the back seat.

ii) Remove the under-steering column cover for the dash, and look up inside (to the right) to find either two or three square relays. These will be plugged in to sockets that are attached to a metal bracket.

iii) To free the relays from the bracket, little clips will need to be unhooked from the tops of the relays (holding them in position) and the big red connector to the right can be released by pulling out the locking mechanism in the bottom of the connector. Once this is done, the relays can be pulled away from the metal bracket.

iv) Put the big red connector back in the socket, and push the locking mechanism to fasten in place.

v) To test which relay is the fuel pump relay, remove a relay and turn ignition to position II. If you can no longer hear the pump buzzing as described in (i) it is the fuel pump relay.

Once the correct relay has been identified and removed, the following voltage checks can be conducted on the now exposed terminals under the dash where the relay should be. To identify which terminal is which, compare them to the numbers on the bottom of the relay. The relay will only fit one way round, so there is no chance of putting it back incorrectly.

vi) Terminal 30 should register about 12 volts all the time (ignition on and off)

vii) Terminal 86 should register 12 volts only with ignition on

According to HBOL
viii) Terminal 85 should register between 0 and 1 volt for three seconds when the ignition is switched on (the time the fuel pump buzzes for) and then change to 12 volts.

ix) Terminal 87 should register 12 volts for three seconds when the ignition is switched on and then change to approximately 1 volt.


If any one does have the kindness to try this check, I would be very, very, very grateful. I am starting to lose hope over this problem, and I have no experts I can ask about what should happen. I am thinking comparison with a known trusty Volvo would be an ideal test.
If you live near the Chesterfield area and have a 400-series Volvo, but don't fancy doing this check, I could also complete this check on your trusty car instead.

Thanks to everyone who has taken the time to read through these long posts, and also help with the other topics I have posted.

[jlgrosvenor]

Additional comments following a 20-mile run after relay replacement.

The two relays I have replaced are quite warm, although not too hot to touch. The relay next to them that didn't blow (plugged in to the red base holder) is ambient temperature. I don't know if this is normal considering these two relays are on the 30 Amp rail. Some of the relays of the same type that are accessed from the top of the engine bay (in front of the drivers windscreen) are of comparable heat after the run also.

I am also a bit confused by the picture of the wiring diagram I posted. The fuel pump relay shows that terminal 85 should connect to pins 22 and 29 on the ECU. If you physically follow the thin, black cable from this pin it is a single strand and joins to pin 6 on the ECU. Oddly enough, the number 6 is shown at the junction with the wiring for pins 22 and 29 on the wiring diagram, but I didn't think this suggests that it connects directly to pin 6. How the hell do I interpret the wiring diagram following this discovery? :confused_smile:

[440driver]

Hi, I also have an intermittent electrical fault on my

440 1.8se (not si) B18U engined '94 car.

Unfortunately I am reliant on the RAC and garages to keep on the road.

The 1st time it died it, it restarted without the RAC man locating the fault.
It again died a mile or so later. A garage borrowed a sensor unit but the car stayed dead. They replaced the ignition module and the car started and ran very well for a fortnight. The same RAC man attended the next breakdown and again restarted the car without knowing what the problem was. I have been advised to drive the car until the fault recurs as (obviously) a fault cannot be detectedwhen its not there. On account of my age and the weather I do not relish a roadside breakdown and so am restricted to very short trips - very inconvenient.
If I get it sorted I will let you know what the problem was. Meanwhile I will follow your tale with interest.

P.S. I have only just joined this Forum and hope this note has not wasted anyones time.

[Paul240480]

P.S. I have only just joined this Forum and hope this note has not wasted anyones time.


No not at all & please do let us know the result when it comes.:thumbs_up:

[jlgrosvenor]

Well, the trusty Volvo seems to be running OK now.

As it turns out, changing the two relays (mentioned and linked to in my first post in this thread) has fully cured the problem. The two relays were broken, and after about 20 hours of electrical testing (including trying other ECUs which also worked fine), I am unable to find anything wrong that might have caused them to break other than the ignition coil (it measured about 6250 ohms instead of the 4000 ohms +/-1500 specified.

I don't know if a duff ignition coil is enough to break the two relays, and the relays seemed to work intermittently for a few runs before giving up the ghost.

Since replacing the relays, I have covered about 1200 miles problem free. The car is running fine, but I keep a couple of relays and my voltmeter in the glovebox. Still not a totally trusty Volvo yet after such a let down.

Fingers crossed.

[Paul240480]

Good news. The relays do have a life expectancy of about 12-15 yrs. The joints dry out & sometimes gives an intermittant fault first before faling completely.

Thanks for teh update, glad you're sorted.

[veegard]

Hello,

I think I have almost the same problem as you...

Car's been driving perfect, except for a very high fuel consumption. But it never stops, always starts - even if it's quite cold outside (live in Norway).

So, one day I was changing the stereo, parked it outside, it rained a bit, and my hood was open.. Don't think that should matter though!
After some hours, I was done, tried to crank it, didn't start. Assumed I had flattened the battery, I charged it until the morning after.
I crank it, starter turns, but nothing more happens.

I check if there's a spark, no spark.
I check if there's a spark in the plug cap, no spark.
I check if there's voltage to the coil. All connections read 0v.

I check the crank sensor (the one at the right side of the engine, way down there...).
I listen for the fuel pump running. No fuel pump.
I try to diagnose the car, but I only get a response from slot #7 (which is ABS or airbag or something)
Socket #2 only gives me a faded weak LED, which gets stronger when I push the button. But no response.
The two other sockets that there's something in gives no reaction other than the light lighting up as long as I hold down the button.
Socket #7 gives me code 1-1-1. No errors.

I shuffle the relays about a bit, the ones that are acccessible from the engine bay.
No change or effect.
I read this thread, read about the fuel pump relays. I try looking for them at the driver side, only to realize that they're at the right hand side, which isn't the driver side here.
I find two relays that look similar to the ones described here. I take them off, one for one and check them.

I ohm the two connected poles. 85 and 86, was it? I get 75 ohm.
When I feed the relay with +12v, the relay clicks. I assume it's working, put it back in. I check the next one, same reults, also appears to be working fine.

When i check voltage in the socket I get exactly the same results as forementioned in the post.
I switch them around in their sockets, to see if that has any effect. Still no go.

I unplug the ECU of the car (the humongous SCART-contact). It suprises me that I cannot see any difference in the behaviour of the car whether I have it plugged or unplugged. The same warning lights flash, the SRS light goes away when it should, oil pressure goes away when it should. As it is now, I don't know if I have a dead ECU, or if the ECU has no power or something.

Which leads am I supposed to check that gives power to the ECU (or other important needed cables)?


The dashboard illuminates, the oil-light lights up, and disappears a second or so when I start to crank the engine.
The stereo works fine :p
Lights, turning signals, heater, everything works as it should when it's off.
When I crank it, everything dims as it should, and the starter sounds very normal.
Never had any problems the one month I have owned the car.
The car has previously had installed a DEFA 800-series alarm, but I think all of it except an unplugged siren and a glass-breaker microphone is left.. I can't find any immobilizer atleast.

Known problems with the car is that it has excessive fuel consumptions (1.4l per 10km, that's like 25mpg-ish, and it's with nice driving too!)
Thermostat probably broken, not showing engine temperature.

The car has gas, oil, coolant and plenty of power on the battery.

Help!

[jlgrosvenor]

Sounds like you car may have a few problems.

What engine do you have, B18U like mine? I am getting 35mpg around town, and 50mpg on very long motorway runs. Typical average consumption is about 450 miles from about 50 - 52 litres of fuel at fill up. For this issue, I would guess that it might be oxygen sensor in the exhaust, or the engine temperature sensor on the front of the head. Both can be checked for appropriate resistances with Haynes manual instructions.

Just a note, the temperature you see on the dashboard does not relate to the two sensors I have just mentioned. There is a separate sensor for the dash temp indicator, and this is on the back of the head on the left-hand side of the car.

As for the car not starting, have you checked the resistance of the windings in the ignition coil pack? I think it is mentioned in this thread.

Good luck.

[veegard]

I have a B20U.

I do think that for a fact, the engine is running very hot. I've noticed how water evaporates very quickly when I drive through puddles, and how the metal "ticks" when I turn it off. I think the engine is oversaturated with gas, but I'm gonna take that problem when I get the car running again..

I haven't, no. But I think I have the bogus connection in reach!

The pin 87 on the fuel injection relay (i have one black socket relay and one white socket relay) is split up into two different leads. One obviously going back to the ECU, and one going.. to somewhere behind my stereo, where it just hangs loose. It's a red and thick-ish wire (looks like it supplies power opposed to being a signal cable).
I have to figure out where it's supposed to be connected, then maybe I get lucky and get to start this thing again!

[jlgrosvenor]

A fast water evapouration and 'ticking' are not necessarily signs of an overly hot engine. If I were you I would be making absolutely sure the resistances on the TWO temperature sensors are correct. I would also be checking for continuity down the wires to the dash and ECU. If you look at the relevant Haynes manual wiring diagram, it will tell you which pins the engine temp sensor should be connected to. If you measure the resistance of the temp sensor, and then measure the resistance across the appropriate ECU scart lead wires, you should get the same resistance reading. I did this for almost all sensors on the engine whilst trying to find a fault.

You can do the same thing for the engine temp readout (dashboard) sensor. This does not connect to the ECU lead, but should be accessibly on the back of the dash (just about anyway).

I am sure you know, but running the car too hot will dramatically reduce it's life, but on the otherhand, I would expect better economy. As far as I can remember, the higher the difference between the air coming in, and the air going out, the more efficient the engine - hence racing cars using higher temperatures and jet turbines seeking better and better materials to push up operating temperatures for efficieny gains.

[veegard]

I'm going to try all that later, right now my main pri. is getting the thing started again.. Which has proven to be difficult.

As you can see in my thread here (http://www.volvo-forums.com/t24624-460-95-b20f-not-starting33.htm), I have a loose wire on the black-socketed relay at the right hand side in the car.
It's red, kinda thick, and goes nowhere. And I saw the same wire while swapping my stereo, maybe I've unplugged it while pulling cables.
And it doesn't seem to be placed very logically at all, I don't really know.. what it does.

[veegard]

Okay, done some more testing now.

Seems like the red wire I was talking about is an aftermarked one, and doesn't belong there.. If it touching anything could have ducked anything up, I don't know!

I have the Fenix 3B aswell, and I don't know where to measure and which values to expect.
I do however get +12v on a couple of the ECU plug connectors.
I could ohm my crank sensor fine from the ECU plug, 218 ohm.
Relays are apparantly working, but will test them again..

[gamel]

The vehicle owner who does his or her own maintenance according to the recommended service schedules should not have to visit and use this section. Modern component reliability is such that, provided those items subject to wear or deterioration are inspected or renewed at the specified intervals, sudden failure is comparatively rare. Faults do not usually just happen as a result of sudden failure, but develop over a period of time. Major mechanical failures in particular are usually preceded by characteristic symptoms over hundreds or even thousands of miles. Those components which do occasionally fail without warning are often small and easily carried in the vehicle.