Intermittent electrical cut out whilst driving

I drive my 91 cabriolet daily to and from work, a 20 mile round trip. Every day it cuts out at least once during my commute, the revs will drop completely, radio will lose power and have no acceleration until I jiggle the wires underneath the steering wheel when it will spring back into life and everything will come back and the car will drive fine again and the temp gauge light will flash like the ignition has been turned again. Many parts have been replaced including; distributor, dizzy cap, ht leads, fuel filter, no rust in tank, ignition switch, carb flange and im sure some more bits. Next option is to wire a direct live switch to the ignition so there is a constant live when I need it. I have scowled the forums but cannot find a solution. I'm steering towards perhaps a grounding issue but where should I be looking? Hopefully someone can enlighten what might be the issue?
TIA

bad new ignition switch….
Make sure that your steering shaft outer cover to ground is intact as well as the steering rack mount ground to steering gearbox is intact.

Cheers for the advice, this is the second new ignition switch as I wondered this from the first change over, this has been going on for a couple of years now. Where abouts are these grounding locations? Presumably along the steering rack somewhere?

There's an earth wire at the bottom of the steering column in the engine bay right near the steering rack.

Have you got a big bunch of keys hanging off the ignition key? If so try removing the keys and just use the ignition key to see if that makes any difference…

found this, I’m not great on electrics so there may be another one for the ignition?

https://vwgolfmk1.org.uk/forum/index.php?page=topicview&id=helllllpppp%2Fearth-strap-from

I tried removing all extra keys the other day and the problem still persists, I appreciate the suggestions though! I will take a look at the ground tomorrow and see if giving it a rub down helps.

Edited my post above   

Sounds like it has just got to be a bad connection under the dash if it works again when you jiggle stuff…..

I would try jiggling  stuff with my head under there and torch, while it's running - if it stops you have found the culprit

All this is making the supposition that your major earth grounds from battery to frame and frame to engine/tranny are good.  

If you feel around your steering shaft outer towards the bottom,  there is a Phillips screw that a ground is usually attached to, the other end is on the Start cluster riveted to the firewall high.

I have tried to simulate the cutting out many times by playing around with the wires but can never get it to cut out. I have sorted some grounding issues today, fitted the one from the carb to the rocker cover and cleaned up battery to body and body to gearbox. I also did the one at the bottom of the steering rack but could only get to the top one, the lower one I just had to spray some connection cleaner on and hope for the best. I'll see how it goes tomorrow and fingers crossed there are some improvements. Thanks for all your suggestions.

Does it do it in any pattern like always around 5 miles, or after 20 mins, revving hard up hill, coasting down hill etc?

No pattern unfortunately, it's totally sporadic. Change in weather makes no difference either. 😩

Drive to work this morning was awful, cut out about 10 times so nothing I did last night made a difference. Gonna pop out at lunch and fire it up and keep jiggling around with wires until I can simulate the cut out, if I can narrow down to where it is cutting out from that'll really make things easier. But for now i'm daffodil in the wind 😂

pedropedallo said

No pattern unfortunately, it's totally sporadic. Change in weather makes no difference either. 😩

bogger, one of those that makes you want to set fire to the chuffin thing. Assuming the tank and fuel lines are clear and fresh fuel does sound electric.

Have you checked the carb stop solenoid and its wiring/connectors?

Or a failing fuse box, has it been soaked in the past?

Does it have an immobiliser fitted? In your first post you mention jiggling wires under the steering wheel seems to do something. Is there possibly a wire that is breaking down or broken within its shrouding or loose within a connection? Also does it cut out on the straight or going round a corner?

Used to have an immobiliser fitted but the thing was on the fritz and going off at 2 in the morning, that went about 6 years ago. I'm starting to point towards a wire arcing out somewhere along the steering rack. I also got rid of the ignition switch plug and wired them all in separately as I thought it could be the plug being iffy.

pedropedallo said

Drive to work this morning was awful, cut out about 10 times so nothing I did last night made a difference. Gonna pop out at lunch and fire it up and keep jiggling around with wires until I can simulate the cut out, if I can narrow down to where it is cutting out from that'll really make things easier. But for now i'm daffodil in the wind 😂

Does it have the original carb and warm air hose from exhaust?

Got the 32/34 DMTL Weber fitted and pretty certain the warm air feed is connected too but will double check on lunch.

pedropedallo said

Got the 32/34 DMTL Weber fitted and pretty certain the warm air feed is connected too but will double check on lunch.

bit suspicious it's a nightmare in cold and damp which might lead to carb icing, it dying and then quickly restarting as the engine heat thaws it out and then repeats. Note it doesn't have to be freezing outside, its more the damp turning to ice in the carb.

The factory warm air gubbins/air filter system is often junked when a Weber is fitted. Also no experience myself but the original E2E vacuum reservior and pipe work are often left and casue weird running.

Wouldn't explain why it springs back into life when I jiggle the wires about though. I'm fairly certain it's something electrical. I'm sure i'll be kicking myself when I finally figure out what the issue is.

Went out to have a little fiddle on my lunch break with a colleague, he found that one of the spade terminals I had put in instead of the ignition switch plug was loose so I crimped it better and now it is firmly in place. Had no cut outs on the journey home so fingers crossed. However this would mean that I solved an issue and created another one by removing the dodgy plug and replacing it with a dodgy spade 😂 I'll see how it goes over the next few days and keep you all posted. I hate a thread with no conclusion…