V6 no spark

[Jack]

Right, the V6 (B308i = X30) currently refuses to start. Scratchy head time.

We have fuel, but no spark. Before fitting in the saloon, the engine started up Ok.

Effectively all we've done is tidied up the loom (all sensors are still attached!) and extended the part that goes to the dispack - however, these wires have good connectivity so no shorts or dodgy joins there.
Replaced: ECU, Dispack, Cam Sensor, Spark Plugs. Haven't replaced the crank sensor (yet) but Lee has checked it and it seems to be Ok.
Everything is earthed Ok, all appropriate wires from the ignition components to the ECU are good.

Lee took a plug out and earthed it on the slam panel, good earth but no spark when turning over.

Is it possible that if the timing was a little out (as in one tooth max) from where we did the cambelt, that either the cam or crank sensor would stop the car from starting? I thought it would start but just run like a bag of nails...

[Ernie]

It would probabaly still run then bend all the valves then sound like a sewing machine then stop imho.

Have you got Dave Marshalls number as he is a bit of a god with these engines.

[ck]

have you checked your coil pack for 12v+?

[Southie]

Any ecu fault codes coming up?

[Southie]

You probably already printed them out, but now you have them backed up here too :D


BOSCH Motronic ECU Fault Codes
This fault code chart shows the Bosch Motronic fault codes for the following systsms:
1.5, 1.7, 1.8, 2.5, 2.7, 2.8, 2.8.1, 2.8.3, 3.1, MP3.1, 3.2, 4.1, 5.1, 5.1.1, First Generation and MPi.

Fault:
12 Initiation of diagnosis. n/a
13 Oxygen sensor No change in voltage/open circuit.
14 Coolant Temperature Sensor (CTS) Low voltage
15 Coolant Temperature Sensor (CTS) High voltage
16 Knock sensor 1 No change in voltage
17 Knock sensor 2 No change in voltage
18 Knock control unit No signal, Engine Control Unit (ECU) fault
19 RPM signal (crankshaft sensor) Incorrect signal
21 Throttle position sensor High voltage
22 Throttle position sensor Low voltage
23 Knock sensor module n/a
24 Vehicle speed sensor (VSS) No signal
25 Injector valve 1 High voltage
26 Injector valve 2 High voltage
27 Injector valve 3 High voltage
28 Injector valve 4 High voltage
28 Fuel pump relay Low voltage
29 Injector valve 5 High voltage
31 Engine RPM signal (crankshaft sensor) No signal
32 Injector valve 6 High voltage
32 Fuel pump relay High voltage
33 Inlet manifold pressure sensor Voltage too high
34 Exhaust Gas Re-circulation (EGR) valve Voltage too high
34 Manifold Absolute Pressure (MAP) sensor Low voltage
35 Idle Speed Control Valve (ISCV) Poor or no idle speed control
36 Incorrect RON/Octane setting Damaged RON plug or bad connection.
37 Engine self-diagnosis (fault code light) Low voltage
38 Oxygen sensor Voltage low (1990 model year on)
39 Oxygen sensor Voltage high (1990 model year on)
41 Vehicle speed sensor (VSS) Low voltage
41 1 gear ident switch (C20LET systems) Low voltage
41 EST Line coil cylinder 2&3 (M2.8/XEV systems) High voltage
42 Vehicle speed sensor (VSS) High voltage
42 1 gear ident switch (C20LET systems) High voltage
42 EST Line coil cylinder 2&3 (M2.8 / XEV systems) High voltage
43 Linear EGR system (XEV systems) Faulty
44 Oxygen sensor Air/fuel mixture too lean (weak)
45 Oxygen sensor Air/fuel mixture too rich
46 Air pump relay High voltage
47 Air pump relay Low voltage
47 Linear EGR Position (XEV systems) Faulty
48 Battery voltage Low voltage
49 Battery voltage High voltage
51 ECU Programmable memory PROM error, hardware failure
52 Engine check light; final stage (fault code light) High voltage
53 Fuel pump relay Low voltage
54 Fuel pump relay High voltage
55 Engine Control Unit (ECU) fault Renew Engine Control Unit (ECU)
56 Idle Speed Control Valve (ISCV) Short to earth
57 Idle Speed Control Valve (ISCV) Interruption
59 Inlet manifold valve 1 Low voltage
61 Fuel Tank Vent Valve (FTVV) Low voltage
62 Fuel Tank Vent Valve (FTVV) High voltage
63 Inlet manifold valve 1 High voltage
63 EST Line coil cylinder 2&3 (M2.8 / XEV systems) Low voltage
64 EST Line coil cylinder 1&4 (M2.8 / XEV systems) Low voltage
65 Carbon Monoxide (CO) potentiometer Low voltage
66 Carbon Monoxide (CO) potentiometer High voltage
67 Throttle valve switch - idle position switch Low voltage - switch not opening
68 Throttle Switch (TS) - idle contact Idle switch not opening
69 Air Temperature Sensor (ATS) Low voltage
71 Air Temperature Sensor (ATS) High voltage
72 Throttle Switch (TS) - full load contact High voltage - Full load switch not running
73 Air Flow Sensor (AFS) Low voltage
74 Air Flow Sensor (AFS) High voltage
75 Transmission switch - torque control Low voltage
76 Automatic Transmission (AT) torque control Engaged long, ignition retard long
79 Traction control unit Incorrect ignition/injector cut-off
81 Injector valve 1 Low voltage
82 Injector valve 2 Low voltage
83 Injector valve 3 Low voltage
84 Injector valve 4 Low voltage
85 Injector valve 5 Low voltage
86 Injector valve 6 Low voltage
87 Air Conditioning (AC) cut off relay Low voltage
88 Air Conditioning (AC) cut off relay High voltage
89 Oxygen sensor heater Low voltage
91 Oxygen sensor heater High voltage
92 Camshaft sensor failure (XEV systems) Faulty
93 Hall Effect Switch (HES) Low voltage
94 Hall Effect Switch (HES) High voltage
95 Hot start valve Low voltage
96 Hot start valve High voltage
97 Traction control unit - ignition/injection cut off Incorrect signal - high voltage
98 Oxygen sensor Open circuit, wiring break
99 Code unknown n/a
113 Turbo boost control Boost presure high, out of range
114 Idle boost valve Above upper limit
115 Full boost pressure Below lower limit
116 Boost pressure Above upper limit
117 Wastegate valve Low voltage
118 Wastegate valve High voltage
121 Oxygen sensor 2 Lean exhaust, weak mixture
122 Oxygen sensor 2 Rich mixture/exhaust
123 Inlet manifold valve 1 Blocked
124 Inlet manifold valve 2 Blocked
132 Exhaust Gas Re-circulation (EGR) valve Incorrect signal
133 Exhaust Gas Re-circulation (EGR) valve 2 High voltage
134 Exhaust Gas Re-circulation (EGR) valve 2 Low voltage
135 ‘Check engine’ lamp (fault code lamp) Low voltage
136 Engine Control Unit (ECU) n/a
137 Engine Control Unit (ECU) box High temperature
141 Secondary air pump Not enough air
142 Secondary air pump Air without pump
143 Immobiliser function in ECU No or incorrect signal
144 No immobiliser signal recived Faulty unit or break in wiring
145 Incorrect immobiliser signal received Faulty unit or break in wiring

[Jack]

have you checked your coil pack for 12v+?

Yup, Lee checked both coils which buzzed through Ok, but we've since been told that even if the coil appears Ok it could still be shonky when it comes to chucking a signal out to the leads.

Any ecu fault codes coming up?

Er, we've not actually connected the eng warning light yet as we were running on minimal stuff just to get the engine running first.

Anyone happen to know what wire/pin number on an X30 ECU plug is for the engine warning light? My haynes is in Lee's barn and he doesn't do wiring diagrams

I also read on a saab forum how someone unplugged the crank sensor and put an LED on it to visually check it was sending a signal back to the ECU.... would that work?

[Sloth]

Yup, Lee checked both coils which buzzed through Ok, but we've since been told that even if the coil appears Ok it could still be shonky when it comes to chucking a signal out to the leads.

true, it will buzz test but it can be faulty.


Er, we've not actually connected the eng warning light yet as we were running on minimal stuff just to get the engine running first.
gerrit wired up....
Anyone happen to know what wire/pin number on an X30 ECU plug is for the engine warning light? My haynes is in Lee's barn and he doesn't do wiring diagrams
it depends what ecu you have, motronic or siemens. if its motronic, its the same as an xe. and should be the same colour, unless its on the saab loom...
I also read on a saab forum how someone unplugged the crank sensor and put an LED on it to visually check it was sending a signal back to the ECU.... would that work?
yes, because an led pulls no resistance, or at most 0.000001ohm.

id say the crank sensor has had a fit, they have the same issues as an xe, so if ya wire it like an xe it should run. but remember it depends on which make of ecu jack. ill go find my motronic v6 wiring diag..

[Lee]

Anyone happen to know what wire/pin number on an X30 ECU plug is for the engine warning light? My haynes is in Lee's barn and he doesn't do wiring diagrams

I also read on a saab forum how someone unplugged the crank sensor and put an LED on it to visually check it was sending a signal back to the ECU.... would that work?

Cheeky beggar . I know my way around the diagram now seeing as I ripped the loom to bits and buzzed through every fecking sensor, live and earth!

LED on crank sensor? Not heard of that but ill give it a go, bar that ill grab a sensor from the scrappies. ctually unplug the sensor and plug an LED into it? or just bridge the terminals whilst its plugged in?

Chris you cheeky turd . Timing is spot on, it turns over perfectly, and we HAVE had the odd burp from it where its tried to start and then stop again.

Question. will a dodgy crank sensor still allow the engine to fuel? as we are getting wet plugs.

Also, this loom was a fecking mess when we got it, there was no diagnosis plug on it, therefore im fecked if I know how Im going to do a paperclip test, but then maybe i need Jack to look at the wiring diagram

[ck]

if its crank sensor the fuel pump will no switch on while cranking the engine over. if it were me i'd quickly wire in a bulb into the fuel pump feed so you will have a tell tale for when the fuel pump switches on.

you can run an LED on an injector plug to see if the injectors are firing. if they are then the ecu is powered up and crank sensor working.

i'd guess at ignition amp or coil pack. i have a coil pack here u can have with the same plug (from vectra and 1 has coil failed 5 working) may help
in identifying the problem

[ck]

where the wiring comes out from the ecu loom to connect to the car loom what colour wires do you have? which wires do you know are correct?