Vectra cut out / stall at speed. | Technical matters | Back Room Forum

What is life like with your car? Let us know and win £500 in John Lewis vouchers | No thanks

Mon 27 Feb 2006 00:25

Vectra cut out / stall at speed. - johnslpg

Hi, I have recently bought a 16V Vauxhall Vectra Estate 1.8 Expression... with a big, mysterious fault.

I have experienced a "cut out" 3 times. I thought at first it was simply my fault for poor clutch control but it's not. The latest time was dangerous - dying on motorway in 3rd lane so I must sort this out before using the car again.

Previously it happened at 20mph going round a roundabout, and at 60mph on the slip road off the motorway. Both times I restarted the engine - no warning light, and off I went without hitch.

In the latest episode the engine light came on, the revs dropped to zero, and dropping the clutch had no effect in restarting the engine. I came to a stop. Turned the engine off, 5 minutes later started her back up and almost immediately the engine light came on, and it cut out.

When running on petrol it idles poorly. Idle control valve possibly blocked? When running on LPG it runs smoothly.

I called out the RAC and half hour later when chap arrived restarted the engine, and no engine light, he checked the engine etc and tried to replicate fault - nothing!

I persuaded him to plug up his fault reader, and it did read faults: injectors 1-4 voltage high (?), incorrect RPM (expected but unrelated?), hall sensor or crankshaft sensor voltage high. He was of the opinion that none of these faults would have caused the cut out. His advice was continue on my way - and I did (in first lane the whole way!!... and for the remaining journey 300 miles ... nothing)

So what caused the phantom cut out? Is it related to the rough idle? Are the fault code readings relevant? Are there faults that don't get recorded?

Help!!

Reply | Report as offensive | Link

Mon 27 Feb 2006 00:41

Vectra cut out / stall at speed. - Dynamic Dave

I realise that on initial start up it runs on petrol, then switches to LPG, but it's unclear from your note (well to me anyhow) that when it cut out on the motorway as to whether it was running on LPG or petrol?

If it's only doing it on petrol, then that *could* be the problem as unleaded petrol has only got a certain shelf life and has a habit of "going off" if it's left lying around for a period of time.

Reply | Report as offensive | Link

Mon 27 Feb 2006 08:06

Vectra cut out / stall at speed. - Number_Cruncher

Voltage high trouble codes would make me want to check *every* earth and connector block on the engine management system wiring. I would probably go to the lengths of undoing each and every one of them, cleaning and/or lubricating just to make sure.

Voltage high trouble codes are set when the ECU detects a voltage that is higher than could normally be expected. This usually is a break in the wiring either between the ECU and the sensor, or between the sensor and earth. It can also be a sensor failing open circuit, but, as you have more than one voltage high code, I don't think replacing sensors will solve your problem. A check of the wiring diagram will allow you to see if the wiring for the sensors which gave trouble code all pass through the same multi-plug, or all use the same earth. If you do find such a common point, there's the place to begin your search.

If it were the alternator overcharging, I would expect also to see a battery voltage high trouble code - so, I don't think it is the alternator at fault. However, checking the battery/charging voltage is only 2 minutes work.

Number_Cruncher

Reply | Report as offensive | Link

Mon 27 Feb 2006 09:35

Vectra cut out / stall at speed. - netlang

It sounds like the throttle body and idle control valve needs cleaning. Try looking at www.VVOC.com there is loads of information on this problem and how to clean the relevant parts.

Reply | Report as offensive | Link

Mon 27 Feb 2006 09:53

Vectra cut out / stall at speed. - Dynamic Dave

It sounds like the throttle body and idle control valve needs cleaning.

Also here:-

www.honestjohn.co.uk/forum/post/index.htm?v=e&t=39...4

Reply | Report as offensive | Link

Mon 27 Feb 2006 10:22

Vectra cut out / stall at speed. - Number_Cruncher

>>It sounds like the throttle body and idle control valve needs cleaning

Not if the engine cuts out in the third lane of the motorway, or while doing 60 as the OP says. Under those conditions, with the throttle at least partly open, the position of the idle speed control valve is quite irrelevant.

If the car were cutting out on the approach to junctions, as the clutch was pressed to change gear, then, yes, I would agree with your suggestion.

Of course, cleaning the throttle and idle speed control valve isn't a bad thing to do, but it won't clear this particular fault.

Number_Cruncher

Reply | Report as offensive | Link

Fri 3 Mar 2006 23:20

Vectra cut out / stall at speed. - johnslpg

Hi everyone, Thanks very much for all your suggestions and input.

I've figured it out - and it was really quite bizarre. There was a air sucking noise that I noticed and a pipe leading to top right side of the engine (distributor or inlet manifold?) that was unplugged. I reconnected and immediately the idle got an awful lot smoother and basically it hasn't happened again. The air/mix was all wrong - so explains the 70mph cut out.

I think that the idle speed control valve still needs cleaning, and thanks for the suggestions on that.

Re - petrol going off - I do run on petrol from time to time for exactly that reason, and to lubricate the engine (LPG is very dry and lacks those additives).

I'd tried the Vauxhall TIS programme and it came back with various parts that could be to blame.... I'm thankful that it turned out to be none of them!!!!!

Next challenge is to figure out why it runs on LPG with over 5% emissions (MOT Failure today) - running a "tad" rich methinks....

Cheers, John

Reply | Report as offensive | Link

Ask Honest John

Sell Your Car

Real MPG

Fuel Calculator