Engine Electrical Problem

[Guest Ian & Carole]

http://www.rimmerbro...CFY_KtAod3TYATw

 

 

I'll get my coat !!!! TAXI !!!!!!!!!!!!

[speedtripledan]

Set fire to it then....I,m gutted really thought we had it at marks bloody car

[Guest MarkB]

Told you my garage is the Bermuda triangle.

[sj-bradley]

Ok Richard. I can bring round a few bits to see if we can trap this signal down.

 

Did you add the capacitors that were shown in one diagram? I have a fair few of these to try if you want to.

 

(firstly though - must get my car Mot'd)

 

Simon.

[richardm6994]

Cheers simon but I'm going to leave it alone for a few months and get some other jobs done. I'll come back to it when I'm in the right frame of mind.

 

I've not added the capacitors as I've read a couple of websites saying not to fit them?

 

 

 

[sj-bradley]

No problem. Let me know when you want to have another go at it.

 

The capacitors should make the 12 volt supply to the coil packs smoother by taking out the large voltage spikes from the back emf induced when the coil is "switched off". You don't really want these spikes going back into the EDIS unit drivers. (They should be protected by internal back emf diodes anyway.)

 

Why do the other sites suggest NOT fitting them and which sites are they? (interested)

 

Simon.

[Longboarder]

Every diagram I have seen shows the shielding for the VR sensor connected to terminal 7. Most show shielding for PIP and SAW also connected to 7 also but some add that connection to 10 as well and most instructions say the shielding must be earthed. Interestingly some label 7 as VR shield earth or ignition earth and 10 as power earth. It does seem that these two terminals have different jobs and linking them is wrong. I would still go with 7 as VR shield earth. I would link 10 to earth with a substantial wire, say 25amp. Where to link the PIP/SAW shield. It must carry a signal very different to the VR shield and I would not want to link the two, nor would I want to link it to the power earth so I would give it a separate earth,16amp wire to the car body. That should make it difficult for funny signals to get back and interfere.

However I don't hold great hope that this will solve the problem but you never know.

 

Another way of looking at it. You have said that this problem was starting to appear in the pinto days, has been getting steadily worse and has persisted despite an engine change and a major change of ignition components.

Suppose this is indeed the same problem? If it is then the same faulty component is still there in the system. It's not in the pinto or V8, not in the edisses (edi?), not in any of the bits you changed. It's a persisting/worsening problem in the rest of the car. There's loads of bits you haven't changed, bits like the fuel tank, pump, filters, fuel-pipes or ignition switch to guess at a few that were there in the pinto days and are still there. It must be one of them.

 

It's just possible I might have mentioned the year it took me to discover that the bullet filters on facet square pumps can block and unblock randomly leaving you coasting or misfiring for seconds or even coming to a halt on motorways or the big circuit breaker I fitted as a safety precaution that left me stranded when it corroded(found that fairly quickly as all the electrics failed at the same time). How about the ignition switch. After all it works the pump. Pump connections in the fuse box? Fuse connections in the fuse box? Have you whipped the top off a float chamber instantly a misfire happens to confirm it's filled with fuel to the correct level?

 

All I'm saying is go back to basics. Assume for a while you have a misfire/cutting out problem that is not the edis/megajolt/coils/leads/plugs. What else would you check? That's where you go from here IMO. Good luck.

 

Nigel

[Guest robinj66]

Sorry to hear you're still having problems.

 

On the basis that it must be something common to both the Pinto & RV8 systems, I reread the whole thread again.

 

I notice from your diagram @ post#56 (when you swopped the coil packs around and made the fault move from one to the other) that one of your plugs (labelled as "new plug") is also common to the fault.

 

Could this be the source of your fault?

[richardm6994]

Robin,

thats a very good point and well worth a look as.

The "new" plug was bought from trigger wheels during the megajolt installation on the pinto.....so this is the only component left from the pinto-days that is common with the rv8 installation.

I have checked the plug with a multimeter and it seems fine, but as I've just bought 2 new coil pack plugs it will do no harm by changing it.

 

Nigel,

I appreciate your response.

We have spent some time looking at mechanical problems that could be effecting it and have come up with nothing.

From the Pinto day's it was a mech fuel pump with a plastic inline filter before the carbs, whereas the rv8 has the facet red-top pump with a one-way valve just after the tank, a glass prefilter before the pump and a filter king filter/reg between the pump and carb.

When the fault happens, there is fuel in the carb.

 

The carb was also brand new.

 

I'd doesn't feel like a mechanical fault as it's not an engine stutter, its a split second engine cut out.

 

 

 

This problem really has gone into the last seconds of injury-time now. If changing the coil pack plugs doesn't fix it, I'm just going to remake the entire ignition loom from scratch!!

[speedtripledan]

Let us know when you do the plugs I might pop over

[Guest zerorace]

just a thought have you tried one of the old style timing lights the sort that flash all the time the engine is running and just have that plugged in then that would show the total loss of spark if it is a full ignition cut

 

 

zerorace

[sj-bradley]

I now have a road legal car again (Thanks Mark B - great service) and can pop over with some kit and see if I can help you.

 

Can't do Weds nights or Thursday though.

 

Simon.

[Guest mower man]

Having watched this from the begining and spoken with you at various times I understand your frustration , you have replaced numerous parts , rewired ,repositioned and generaly been through the system ,I may have missed it and it is not a simple stepbut but have you /can you try a different Megajolt pack,if I 'm talking bull crap ok but it seems that its the only thing you havent changed /replaced apologies if I'm out of line regards mick

[Guest MarkB]

I now have a road legal car again (Thanks Mark B - great service) and can pop over with some kit and see if I can help you.

 

Can't do Weds nights or Thursday though.

 

Simon.

 

I need to do the thanking Simon, you walked in as I was about to launch our computer due to it refusing to print, you sat down did your bit and had it working in minutes.... Top man

[richardm6994]

Zerorace - bl00dy good idea! Thanks

 

Simon - Thanks again for the offer however I've thrown the teddy out of the pram with it at the moment so I'm getting on with other projects like Terry's supercharger.

 

Mick - When I had this same problem on the Pinto, I was running a different megajolt box becasue it was a TPS setup. When I did the V8, I sold the TPS megajolt box and bought a new MAP megajolt box. Both megajolt boxes were bought new from triggerwheels.

Also the problem still happens when the Megajolt is unplugged and the engine is running in "limp" mode directly off the edis. I'm confident both Megajolt boxes are fine.