Idle Problems with Pertronix

[yellowbeard]

Hi guys, I have changed my points and condenser out to the electronic. off of ebay, ever since then my gt will not idle, and backfires out the exhaust. (pertronics) thanks Joe

[kwilford]

Originally Posted by yellowbeard Hi guys, I have changed my points and condenser out to the electronic. off of ebay, ever since then my gt will not idle, and backfires out the exhaust. (Pertronix) thanks Joe

Did you:

1) re-time the ignition? (it WILL be wrong otherwise!)
2) switch a plug wire on the cap or spark plug
3) wire the Pertronix correctly (non-resistor power supply to the Pertronix, either resistor wire to the stock coil or internal-resistor coil, etc etc...)
4) make any other changes?

[Anonymous D]

There are "knock off" units often sold on Ebay. These resemble the Pertronix kits, but are actually cheap Asian substitutes (and have received complaints of not working well, right out of the box).

Did you buy your kit from a reputable dealer, or did you shop instead for the lowest price?

[P.J. Romano]

Originally Posted by yellowbeard Hi guys, I have changed my points and condenser out to the electronic. off of ebay, ever since then my gt will not idle, and backfires out the exhaust. (pertronics) thanks Joe

Your electronic ignition is likely not Petronix but a copy. Still, this is not bad system for the price. Before I installed Compufire, I was using that ignition from eBay for two years without any problem.

- The symptoms that you described are often the result of improper timing. Dropping electronic ignition instead of points, disturbes the timing even if you did not move the distibutor. With classic ignition system (points), it is easy to set-up the timing. With electronic ignition you need proper timing strobelight gun.

- If the distributor is not in a good shape, electronic ignition will not work well as maintaining the proper gap between distributor cam and ignition sensor is crucial. If this gap is constantly changing due to loose distributor shaft, the igniton will not work properly, even if this was not so obvious with the old (points) ignition.

- Also, if your spark plug cables are not in a good shape, electronic ignition will exaggerate the problem due to higher voltage.

These are the facts that are important for any electronic ignition conversion.

[tekenaar]

Originally Posted by kwilford Did you: 1) re-time the ignition? (it WILL be wrong otherwise!) 2) switch a plug wire on the cap or spark plug 3) wire the Pertronix correctly (non-resistor power supply to the Pertronix, either resistor wire to the stock coil or internal-resistor coil, etc etc...) 4) make any other changes?

. . . sorry to disagree, Keith, but timing is not affected by changing from points to Pertronix trigger. Timing may be fine-tuned slightly after the fact, but there is no change from what it was with the points . . . if they were timed properly, that is!

[kwilford]

Originally Posted by tekenaar . . . sorry to disagree, Keith, but timing is not affected by changing from points to Pertronix trigger. Timing may be fine-tuned slightly after the fact, but there is no change from what it was with the points . . . if they were timed properly, that is!

Well Otto, then we will agree to disagree. Even simply changing the gap of points will change ignition timing, as "timing" (when the coil actually fires) is dependent upon the exact event when the coil primary voltage is grounded. That is why the timing has to be set after replacing, or simply adjusting the points, even if the distributor itself is not moved. Installing a different triggering mechanism MIGHT not change the timing, but in most cases it will, even if the ignition was timed properly with the points. The timing will only stay the same IF (and only if) the Pertronix trigger HAPPENS to be set in such a place as to fire the coil at EXACTLY the same place as the mechanical points. I'm not talking 20 degrees here, but it's certainly within a few to ten degrees.

[First opel 1981]

Originally Posted by yellowbeard Hi guys, I have changed my points and condenser out to the electronic. off of ebay, ever since then my gt will not idle, and backfires out the exhaust. (pertronics) thanks Joe

When you installed the Pertronix did you use the gauge included to set the gap? It needs to be (I believe from memory) .030 which is the exact thickness of a standard credit card.

[Aardvaark]

Originally Posted by kwilford Well Otto, then we will agree to disagree. Even simply changing the gap of points will change ignition timing, as "timing" (when the coil actually fires) is dependent upon the exact event when the coil primary voltage is grounded. That is why the timing has to be set after replacing, or simply adjusting the points, even if the distributor itself is not moved. Installing a different triggering mechanism MIGHT not change the timing, but in most cases it will, even if the ignition was timed properly with the points. The timing will only stay the same IF (and only if) the Pertronix trigger HAPPENS to be set in such a place as to fire the coil at EXACTLY the same place as the mechanical points. I'm not talking 20 degrees here, but it's certainly within a few to ten degrees.

Plus if you had set the old points gap with a dwell meter before final timing, dwell meters read an average of all points openings per dizzy revolution and not as consistent as the electronic trigger would be most likely. I'm tending to agree with Kieth at this point. Final timing should be set after any spark plug gap or dwell settings have been made. Jmo.

[wrench459]

Also you might try hot wiring the B+ side of the coil.
A test light on the negative side might also help to see if its triggering some what properly.

[hrcollinsjr]

I think we're nitpicking here. Changing the point gap/dwell changes the timing but changing the timing doesn't affect the timing. When changing to the Pertronix there is a good chance the timing will be affected. How much? My guess would be less than 5 degrees probably closer to 2 or 3. Enough to argue about, not unless you just want to. I do remember someone admitting to "fine tuning" aftet the installation. Hint: They know there is a chance it may affect the timing slightly or maybe it wasn't perfect to start with.

Harold

[tekenaar]

Originally Posted by kwilford Well Otto, then we will agree to disagree. Even simply changing the gap of points will change ignition timing, as "timing" (when the coil actually fires) is dependent upon the exact event when the coil primary voltage is grounded. That is why the timing has to be set after replacing, or simply adjusting the points, even if the distributor itself is not moved. Installing a different triggering mechanism MIGHT not change the timing, but in most cases it will, even if the ignition was timed properly with the points. The timing will only stay the same IF (and only if) the Pertronix trigger HAPPENS to be set in such a place as to fire the coil at EXACTLY the same place as the mechanical points. I'm not talking 20 degrees here, but it's certainly within a few to ten degrees.

. . . well, I can tell you from personal experience and having done this at least two or three times over the last 31 years, ever since my first Perlux (now Pertronix) installation on my then just completed '75FI installation in my '73 GT, my very first Opel. I disconnected the vacuum lines from the distributor, plugged them and checked 'points' idle timing with timing light . . . I was curious, some would say . . . anal.

Then installed and wired Perlux/Pertronix trigger, adjusted to .030" gap, changed nothing else and checked timing again with timing light . . . every time I tried this, always measured within 1-2° of points timing. Have to admit that I haven't felt the need for this check in the last 10 years or so. Do still verify the Pertronix timing after each installation though . . . just don't bother with the prior points check any longer.

[Ray Morley]

I hope the disk was installed correctly over the cam lobe. It would be very easy to intsall this improperly especially if the lobe has worn down a bit.

[american opel]

i bought one of those once.when i was checking the gap{which i do believe is .030"}as i turned the distributar{i put it in a spare points dis.}the plate was out of center or worped.it would change the gap by .014".i sent it back to summit and bought a new distributor insted.

[Aardvaark]

Originally Posted by hrcollinsjr I think we're nitpicking here. Changing the point gap/dwell changes the timing but changing the timing doesn't affect the timing. When changing to the Pertronix there is a good chance the timing will be affected. How much? My guess would be less than 5 degrees probably closer to 2 or 3. Enough to argue about, not unless you just want to. I do remember someone admitting to "fine tuning" aftet the installation. Hint: They know there is a chance it may affect the timing slightly or maybe it wasn't perfect to start with. Harold

Hey! This is a major controversy! Lets not just blow it off!

I checked and maybe fine adjusted the final timing on both Pertronix installs I did.
But honestly don't recall if I re-adjusted it.

[Kadett Rescue]

Keith is absolutely correct on timing comment. You can bet it will be off and you wont know till you check it.

[markandson]

Great argument but we haven't heard if yellowbeard got his problem solved.

[kwilford]

Originally Posted by markandson Great argument but we haven't heard if yellowbeard got his problem solved.

Otto and I aren't "arguing", merely fully discussing the issues at hand

But yes, what is REALLY the issue is yellowbeard's back-firing problem. Any updates on that?

[Kadett Rescue]

Please don't call me crazy but I ran into a similar problem as Yellowbeard once after changing to a higher output coil. Ran my self nuts and finally replaced my ( already recently replaced ) plugs. They still looked very clean but after changing them for new it ran perfect. It was the only changei made on that step. Just a thought..............

[Aardvaark]

So, if all else fails, here is a link to the Pertronix .pdf installation instructions.

Step 17, the last step, clearly states that after starting and warming up the engine, timing should not be not checked probably because they think it might not, not change, or maybe they do and it will, or maybe so it can just be checked and adjusted if not needed.

http://pertronix.com/support/manuals...itor12vpos.pdf

[hrcollinsjr]

Originally Posted by Aardvaark ... or maybe so it can just be checked and adjusted if not needed.

Mark stop it please!

Harold

[RallyBob]

I've done more of the Pertronix installs than I care to remember. IF the car had points that were not perfectly adjusted previously, then YES, the timing almost always needs to be adjusted after the Pertronix installation.

Sure, if the dwell was 50° previously it should be 'dead nuts', but in reality points are a consumable item and are in a state of decay from the moment you install them.

JMTCW

[hrcollinsjr]

Originally Posted by RallyBob IF the car had points that were not perfectly adjusted previously, then YES, the timing almost always needs to be adjusted after the Pertronix installation. Sure, if the dwell was 50° previously it should be 'dead nuts', but in reality points are a consumable item and are in a state of decay from the moment you install them. JMTCW

Interesting, in that the specs for dwell are in the 2000+rpm range but initial timing is set at a much lower rpm. No differences there.

Harold

[Kadett Rescue]

Harold,
Doesn't the Pertronix (like most Elect. Trigger Ignitions) have a dwell altering circuit that increases coil saturation?? I have to agree with your last post. The timing should be set idle speed. The dwell is "decided" by the module (p-tronix) and cant be adjusted. The issue of dwell degrees doesn't really matter AFTER the Pertronix is installed does it or am I just totally off on my thinkin?? : )

[hrcollinsjr]

Originally Posted by Kadett Rescue Harold, Doesn't the Pertronix (like most Elect. Trigger Ignitions) have a dwell altering circuit that increases coil saturation?? I have to agree with your last post. The timing should be set idle speed. The dwell is "decided" by the module (p-tronix) and cant be adjusted. The issue of dwell degrees doesn't really matter AFTER the Pertronix is installed does it or am I just totally off on my thinkin?? : )

When I was referring to checking the dwell, I was talking about points. The dwell isn't adjustable on any of the Elec. Ignitions that I've seen. I've checked the dwell on the Pertronix units before out of curiosity but can't remember what it was, but I do remember it wasn't 50+/- 2 deg.

As far as your first statement it sounds like you understand it better than I do. From a logical standpoint I would say your assumption is correct. How can the spark voltage be greater with just the addition of a different triggering mechanism UNLESS the coil saturation is increased.

Harold

[yellowbeard]

I adjusted the timing and it helped, but still did not idle like it did with the points. And it would miss going down the road. Also backfire when slowing down.