Electrical Fault?

[siwebster]

Hi, got an interesting one for you all. Well, I say interesting...

I've had an intermittent electrical fault with my Chim, it has symptoms similar to the hot start problem some people experience, except this happens at any time, hot or cold and completely randomly. Basically, when I try to start the car the fuel pumps prime but then the starter won't engage. When this first happened many months ago I had a look at the fuse board, etc and by simply moving the ecu out of it's position it started and ran fine...for a bit. When it stopped again a few weeks later it made me think that something near or to do with the wiring connecting the ecu might be have a bad connection, so I removed the ecu, checked and cleaned the connections, plugged it all back in and everything worked fine... for a few more months. Last week it happened again (after it sitting in my work car park all day, so not hot) so I fetched everything out from behind the kick board, checked connections were tight everywhere, wiggled things about a bit and after about half an hour of this it worked again. I left everything out in the passenger footwell as I thought that maybe putting it all back would cause it to stop again, with the thought I'd have a closer look this weekend. This morning I've driven in to work, everything working ok, just gone to move it (after it being sat for 4hrs or so) and it won't go.

Has anyone else experienced anything like this? If so can you point me in the right direction please? Is it a possible broken wire (if so, which one)? Could it be a bad earth somewhere? Any help will be much appreciated... Cheers, Si

[StreetDragster]

Sounds like the starter motor solenoid sticking to me, time for a refurb/replacement. Its happened before to me, and hot/cold/wet/dry didn't effect it.

To test it, when it happens again, is there a click and then nothing happens? Tap the side of the solenoid on the starter with a small hammer, and try again.

Thanks

Matt

[Ribol]

Someone recently posted on here that their immobiliser was playing up and that caused a similar problem.
To test it they thumped the dash where the alarm is(above passenger's knees) and that got the car going.
Whilst I am not suggesting that to get a TVR going you need to thump the dash, it got them home until they could fix it properly. Worth a try?

HTH

[siwebster]

StreetDragster said:

Sounds like the starter motor solenoid sticking to me, time for a refurb/replacement. Its happened before to me, and hot/cold/wet/dry didn't effect it.

To test it, when it happens again, is there a click and then nothing happens? Tap the side of the solenoid on the starter with a small hammer, and try again.

There's no clicking which I would have thought the starter solenoid would have done if there was a problem there - is it possible to have a fault with starter or solenoid like this without any without any noise?

Cheers

Si

[siwebster]

Ribol said:

Someone recently posted on here that their immobiliser was playing up and that caused a similar problem.
To test it they thumped the dash where the alarm is(above passenger's knees) and that got the car going.
Whilst I am not suggesting that to get a TVR going you need to thump the dash, it got them home until they could fix it properly. Worth a try?

HTH

That could be a possibility - I had the top off the dash last weekend I might have moved something, but I guess that wouldn't explain why it didn't work previously. I've got to take it out again to improve/upgrade the dash so that might be a job for this weekend... oh joy.

[steve-V8s]

One of the several things that are normally disabled by the immobiliser is usually the starter solenoid. In my experience whatever it is in the immobiliser box of tricks is no longer able to pass the required current to fire the starter solenoid, the supply can either become intermittent or give up completely. Easy way to prove this if it is intermittent is to attach a wire to the starter solenoid and a wire to the switched output from the starter switch and bring them both to a point where you can get at them. When you have the fault condition measure voltage between each point and –ve (outer of lighter socket). I suspect you will find a good 12v at the switch and a lot less at the solenoid.

[siwebster]

steve-V8s said:

One of the several things that are normally disabled by the immobiliser is usually the starter solenoid. In my experience whatever it is in the immobiliser box of tricks is no longer able to pass the required current to fire the starter solenoid, the supply can either become intermittent or give up completely. Easy way to prove this if it is intermittent is to attach a wire to the starter solenoid and a wire to the switched output from the starter switch and bring them both to a point where you can get at them. When you have the fault condition measure voltage between each point and –ve (outer of lighter socket). I suspect you will find a good 12v at the switch and a lot less at the solenoid.

Thanks Steve, if this is the case what's the best route to fixing it - would I need a new immobiliser? If so do you know how much/where I can get one from? Cheers for your help, Si

[bam50]

Simon, it sounds like one of the alarm immobiliser circuits/relays is playing up. I've found these comments from another entry, credit to the original posters:-

mark TVR-loud said:

I would give Carl a call on 0772 0723407 who is a specialist in these alarms (Car & Bike Installations Ltd - Advertises in Sprint too). He's a very knowledgable and helpful guy, knows the meta system inside out. Sure he will be able to help.
Good luck :-)

and

Big Al. said:

Give Carl "The META man" a bell, he'll probably tell you the fix over the phone.

http://www.tvruk.tv/

Carl's name is mentioned on many/most of the alarm problem posts. HTH

[siwebster]

Thanks for the number Brian, if things get really bad i'll give him a shout.

Managed to get it started, not 100% sure whether this is an immobiliser problem or not now. I went through all the wiring I could get my hands on - I was at work but luckily had a screwdriver and a 10mm spanner in the car, so managed to open up the left hand side of the dash top to have a quick look through, everything seemed fine so I was kind of resigned to the immobiliser fault - but as a last resort I went through the wiring by the fuse box again and moved the wire running to the 100amp fuse from the battery out of the way to have a look if there was anything missing, didn't touch anything else and tried it one last time just out of desperation. It fired up straight away! My theory now is that either the connection of this wire to the battery is bad or the wire is broken and this is causing the fault. Going to explore this at the weekend and trace the wire through and see if this is a feasible answer - unless in the meantime anyone out there knows better! Cheers for your help so far everybody, I'll post up what i find out.

Cheers
Simon

[Pasco]

Have you changed the 100 amp fuse ?

Sometimes this can cause symptoms similar to yours if it is corroding

[shake n bake]

almost definitely a starter motor fault.

[bigdods]

shake n bake said:

almost definitely a starter motor fault.

Could be a sticking solenoid, try turning the key to the start position a few times in rapid succession (but dont hold it at start if it doesnt fire). When I had a bad sloenoid that would sometimes kick it into life. ALso get a hammer and give the solenoid a tap then try it again.