vw passat 2004 tdi saloon
Water under the drivers seat, carpets all wet through, where is water coming from, any ideas?
Read more

I've got a 65.000 mile MX-5 I've owned for 5 years. Previously (say 10,000 miles ago) I had a intermittant failure of 1 of the 2 coils when it would run on 2 cylinders from time to time. Replacement of that single coil solved it, but I also changed the HT leads and plugs prior to the coil.

I've never had any other engine problem with this car until recently. Symptoms have varied a bit, but there is a sort of pattern. Generally it will fire and start, but it will either stop within a few revs, or idle and hesitate every few seconds, and then stop, or idle OK for longer, hesitating occasionally, and then stop, or it might run perfectly. If it decides to run, I can drive it and have driven it for 10-20 miles without a problem until I try to start it again. It does not seem to be any different when hot or cold, except that it seems less problematic starting if it had just been running OK. So it seems a bit different from the other threads here.

When it does stop this way, it makes an unusual sound rather like a rattling relay or mechanical valve which seems to be coming from the front of the inlet manifold area. When it stops by switching it off normally (by switching off with the ignition key), this sound does not occur.

I've asked lots of local garages for help and suggestions. Generally I was advised to look for electrical connector problems. I have removed, dried, re-connected and sealed every engine-related connector I can find in the engine bay apart from those at the bottom of the coils (lazy me, they are difficult to access) but I didn't believe they could be the problem as it either runs or doesn't run, never running on 2 cylinders. Sometimes after doing one I've tried it and it started OK and I thought I'd solved it. Sometimes I could stop it and restart it OK, but on leaving it a few minutes the problem has come back, so clearly it was a red herring. This has happened several times so I no longer think any of these was problem.

I have a fuel pressure guage fitted to the injector gallery and know that my fuel pressure is OK.

I have removed the ECU from the footwell and found it dry and not corroded in any way.

In desperation I took it (it started and drove on that occasion) to a local garage earlier this week, which has a range of engine diagnostic computers as they do rally tuning. They failed to find any fault (apart from seeing it perform its new tricks). They had the computers on its diagnostic port and diagnostic oscilloscope on various sensors and reckon they saw normal waveforms. They believed it is the ECU but were unable to test it. For 4 hours of failed diagnostic work I got charged £230. Ouch!

My local Mazda dealer offered little hope here, saying they could not test the ECU, and replacement for a test is difficult as the ECU is linked to the immobiliser and they had an MX-5 that had been in there for 7 weeks with an ECU problem that they couldn't solve! They suggest leaving it until the car fails to start at all, thus making it easier to find (they hope). So I've avoided taking it to them at least at the moment.

The previous owner fitted a Cobra Thatcham 1 immobiliser which might be the problem I suppose, although I doubt it. Circumstantial evidence here is that the passenger door central locking has not been working for about a year and it is a signal problem because I've tested the door solenoid and it works fine. However since it went to the garage I've noticed that the central locking causes this door to lock, but won't open it still. The driver door locking works fine. They claimed not to have touched the immobiliser, so maybe that's another red herring.

As a final piece of information, I fitted a Jackson Racing supercharger to it soon after I bought it which has been faultless (and extremely good fun!) and is believed not to be part of the current problem.

From other threads I see that replacing a "coil pack" might be a sensible move in view of comments in one thread about one coil affecting the other one. Given that I replaced one coil as mentioned above, what does this mean? Both of the coils situated right at the back of the engine next to the firewall, or something else?

Usually, when it is being troublesome which is maybe 95% of the times I try to start it, if I open the throttle with it idling, it will stop immediately, although sometimes it picks up a few 000 revs whilst coughing, barking and backfiring badly. When it stops on its own from idling, there is sometimes a slight backfire.

Before I go out to do some random chequebook engineering, can anyone please help with these symptoms?

Many thanks. Read more

Our 1.4tdci wouldn't start after having been left overnight. I checked that there were no lights or electrics left on and it seems that nothing was. We jumped it and got it back home but the headlights appeared dim and the battery light was still on after five minutes of running the engine above tickover.

I checked the voltage across the battery with the engine running but it was only 9.5V making me thing that there is a problem with the charging system. I'd went to check the hand book but then remembered that I'd found it in the spare wheel well soaked with water and basically a solid block of paper . So I checked my Haynes only to find out after reading half the book that it was for our old R reg fiesta not this one.

Any ideas what I should check next? Battery terminals appear to be fixed ok. Is it easy to check continuity between the battery and the alternator? Remember I don't have access to diagrams to see where items like the terminals on the alternators are.

Any help appreciated.
Thanks
CJ Read more

Next car to come onto our radar is a 2007 Fabia (newer shape) 1.4TDi 5dr. I wonder if anyone has experience of these? All I've really found on a site search is someone who found the ride was so hard they traded it back in... that might be an issue for us if true. Read more

Hi there

My Mondeo Mk2 (2000) is giving me a bit a grief so hopefully somebody on here can help.
On Sunday night, I had travelled about 4 miles, I was quite close to home when the engine (1.8L) cut-out and refused to start again. I have had no problems before that. The engine turns over but won?t fire

This is what I have done so far:
Checked the fuel pump, it is priming
Checked there is fuel getting into the cylinders (wet plugs and vapour when plugs are out)
There is no spark (plugs out and earthed, cranked engine)
I checked the coil and it had no continuity between 1 and 4, 2 and 3 are ok, so I?ve replace the coil. Still nothing
I have checked all the fuses, they?re fine
The alarm/immobiliser seems to be behaving itself. Red light flashes as it states in the handbook when arming / disarming
I?ve checked the crank sensor, resistance as per manual, and it increases when cranking. I?ve also checking continuity back to the ECU connector
I?ve checked the feed to the coil (3 wire connector). With ignition on, its 12v on the centre cable and 0v on the outer ones. When cranking the centre cable drops to 9.5v but still nothing on the outer 2. So it looks like it isn?t getting a signal from the ECU. I have checked the continuity back to the ECU connector and that?s ok for both the outer cables
I have now drawn a blank. What do I check / do next? Read more