Idle & Off Throttle Hang - Sometimes

[brindo]

I don’t really know much about Nuclear Powered Modules theory surrounding separating the brown coil wire out of the loom, but this would seem to be the perfect opportunity to either prove or disprove his claims. Wouldn’t cost much to run a separate wire from the coil to the ignition module as opposed to some of the alternatives and would be easy to do while you were replacing the coil. If it doesn’t fix it, you’ve lost nothing, and if it fixes it, all good.

[Monarols71]

I was going to run another coil wire and see what happened (nothing to lose), but now we've got a very slight miss occasionally
Nothing has been done to the car yet, as the laptop has been reclaimed and we have no way of logging.
Any more testing will have to wait a while.

[Monarols71]

Whilst doing some more research, I came across this, on another forum relating to a VT 5.0L.

"ok so here it is, at the end of last week we had a high end diagnostics tech visit and check over the car. neways long story short what he found that the variable pressure solenoid was creating a noise along the est(electconic spark timing) circuit which was upseting the ecu giving us the intermittent injector pulse. the way in which he fixed this was to make up a basic noise supressor which on his scope aressted 99% of the noise and instantly the car ran better.

goes to show sometimes you can change so many different things but without the right tools you will never find the problem. the scope this guty bought with him was worth over $40k and looked like something you would only ever see in a specialist brain surgery clinic by far amazing and a good learning curve"

I'll definitely be looking into the wiring "fixes", at least the ignition ones.

[Monarols71]

We finally bought a cheap laptop with a usb port so we can keep logging, but we're having trouble connecting to tunerpro. We have to turn echo off, save, connect, disconnect, and then have to turn echo back on, save and connect to get it to read properly. The laptop won't connect first time with echo on.
We have put a new ignition module in the car, but we still get the DTC49, even though it has been cleared and the cam signal seems to be present without any misses.
Here is a log with echo off. Definitely not correct with all the DTCs flashing on and off.
Regards

[antus]

is this with the latest (1.25) version of the plugin? if so, can you try with v1.24 which is archived at the bottom of the first post in the plugin thread and let me know if the older one works any better?

[Monarols71]

Thanks antus. I'm not using the plugin. I do not have an nvram setup. I didn't think it was needed for standard type ECUs, but I'm not real clever with these things??
Regards

[VL400]

Yeah wont need to use the plugin so can leave TP using internal data acquisition. Which ADX are you using? The VS 3 PCM will need to use a slightly different A5 XDF to the VT.

[Monarols71]

Thanks VL400. I've been using $A5 Engine and trans TP5v103.adx. Maybe I should try the VX s-c Engine and trans TP5 v101.adx.
Thanks

[Monarols71]

The DTC49 has disappeared. We put a new OEM distributor in, and now we don't have any more cam sensor signal missing problems. We'll try and get the old distributor checked, as the module in that is only six months old. We'll still do the coil and the leads when our funds are better. I might still rerun the distributor signal wires in shielded cable to the ignition module and PCM for extra insurance.
Thanks for all your input. Half way there, now.
Now for some more logging to try and stop this slow return to idle problem.

[Monarols71]

Hi again all. Had a slack couple of months and now re-energised a bit . We finally got around to dismantling the old distributor and taking the module back to the seller. They sent it back to the big island somewhere for testing, and after a few weeks they contacted us. I don't think they believed me when I took it back and said it was possibly faulty. Sure enough, it was.
Missing cam signal definitely cured, with no wiring mods.
The miss we had got worse, so in went a new set of decent leads and a new coil. Runs extremely well now, with no DTCs or misfiring, and seems "crisper" (If that makes sense) with the throttle input also.
Still has that same problem, but now that mechanically the old girl is back to where it should be/was, I can start to get some more logging done and some more fiddling and learning.