Engine cutting out whilst driving

[Cockey]

Sure I've read this happening before but the search function is (still) not working!

The engine has decided to start dying whilst on the move. Only happened a few times so far, first being a couple of months ago, but it's happened twice today. It fires up immediately (don't even bother attempting to stop now) when restarted. All the electrics still work and there's a diagnostic code L displayed on the pod when it happens. This is erratic road speed error which I've no idea what it means.

Any ideas?

[nawarne]

This is the list of the error codes:

A - Speedo sensor not activating zero switch
B - Speedo sensor not releasing zero switch
C - Water level sensor not activating zero switch
D - Water level sensor not releasing zero switch
E - Fuel level sensor not activating zero switch
F - Fuel level sensor not releasing zero switch
G - Water level sensor open circuit
H - Air temp sensor open circuit
I - Oil temp sensor open circuit
J - Oil pressure sensor open circuit
K - Fuel level sensor open circuit
L - Erratic road speed sensor input
O - No communications between analogue and control

I'm not certain, but wonder if the ecu requires 'road speed input'?
Might be worth cleaning the toothed wheel and the speed sensor near the diff?
Nick

[ericgreveson]

I've had diagnostic code L while stationary (with engine running) a fair few times, and it hasn't affected anything. Also had a continuous diagnostic code L while driving in very cold temperatures over winter, and again it didn't seem to affect anything other than the speedo display! Perhaps the diagnostic code appears due to an electrical blip when the engine cuts out, and there's a different underlying (electrical?) cause for both issues...

[Cockey]

Thanks for that. Yes, I think the code appears after the engine cuts out. Maybe it doesn't like me rolling with the engine not running?

I'm in gear as this happens, therefore it's the equivalent of trying to bump start a car but it not firing. Guess this means it can only be either the fuel or an electrical issue?

[JnP]

Happened to me once, I refueled too much.
Now if it happened following you refueling the car, I guess you can be reassured. If not... I'm sorry I can't help you much.

[nelly1]

Possible causes (in order of likeliness / easiness to check):-

• Crank sensor - connection suspect, sensor faulty, excess metallic debris on magnetic pickup face.

• Ignition supply fault - ignition relay loose / dirty contacts, loose connection to passenger's footwell fuse, bad loom connection at bulkhead connector, etc.

• Bad earth connection.

• Dodgy ECU connection at connector or faulty ECU.

[Cockey]

nelly1 said:

Possible causes (in order of likeliness / easiness to check):-

• Crank sensor - connection suspect, sensor faulty, excess metallic debris on magnetic pickup face.

• Ignition supply fault - ignition relay loose / dirty contacts, loose connection to passenger's footwell fuse, bad loom connection at bulkhead connector, etc.

• Bad earth connection.

• Dodgy ECU connection at connector or faulty ECU.

Thanks Nelly, that's really great. Car is also running a little rough at lower revs which seems to have coincided with this cutting out. Only really been happening since the steering rack was taken out and refitted, but maybe that's just a coincidence,

[nelly1]

Cockey said:

Only really been happening since the steering rack was taken out and refitted, but maybe that's just a coincidence,

IIRC there are a couple of major looking earth connections looking down into the engine bay at one of the chassis crossbeams at the front in the region of the steering rack?

Edited by nelly1 on Friday 15th June 22:25

[Cockey]

Whilst not getting to the bottom of this problem yet, I have worked out a new way to search the Tuscan forum and have found loads of decent posts about this.

Sounds very much like it could be the fuel pump relay switch. At least my symptoms appear to be near enough identical to others who have had my problem.

Btw, to search properly you you need to open Google and type siteistonheads.com/gassing followed by what you're looking for. The PH search only uses siteistonheads.com and this doesn't seem to ever throw up any decent results. Half my recent posts could've been avoided had I realised this!

[Cockey]

Just to conclude this thread, I've managed to sort the problem out

Turns out it was the fuel switch relay (it's the tallest relay sticking out of the fuse board) which was playing up.

Whilst not having exactly the same symptoms as others to begin with (because I was able to restart the engine immediately), as of last weekend the car started to cut out and refuse to start for a little while.

The TVR part number is M1317. Otherwise you can can buy a Durite 0-723-23 relay or call a Vauxhall dealership and quote one of these part numbers: 90225811, 90230894, 90240698, 90378651 (think they're all the same item in their system). Despite some previous threads stating that it's a £12 part, the cheapest I could find was ordering through TVR Power at about £37 incl delivery. Most places have it at approx £30 incl vat plus a huge delivery charge. Picking up from Vauxhall would've come to £45

The other day my mechanic mentioned how my steering felt a little heavy, and it might be in my mind, but it suddenly feels a little lighter since fitting the new relay. Did I read somewhere that the power steering has something to do with this relay too?