'86 930 CIS Ignition Issues Seemed To Start When Alarm Issues Started
 

Over the weekend, the alarm on my '86 930 started beeping when the driver door was wide open. Seemingly at the same time, I had a little trouble starting the car. At that time the alarm was not going off.

Engine is CIS with Permatune.

Ran great for a day then on a 1 hour drive, I lost idle halfway through the ride. Engine would die immediately when left to idle although would still run great when on the throttle.

After the ride and engine cooled down, it was very hard to start; had to try about 15 times before I could get it to start. This was with opening the throttle like starting a carbed car. I opened the idle screw to get it to idle at 1k RPM but was running rough.

Wanting to eliminate the alarm from the issue, I bypassed the alarm as detailed in many threads (61-61 and K1-15). Now the fuel pumps run any time the car is on. The car was still very hard to start.

Got it started and let it idle for about 10 minutes to warm up. Then the engine started idling very rough and the tach was bouncing crazily all over the place. I jumped on the throttle to try to rev the engine and it died and wouldn't restart. Tried squirting starting fluid and still no start.

I think it's ignition related. I have Peratune with a standard Bosch blue coil. Also found the advance can on the distributor is leaking and doesn't work. Not sure if this is new or not.

Questions:
1) Where can I get a new/used advance can? Philbin in Oregon won't repair it.
2) If I want to put a different CDI unit in, which one to purchase?
3) Is the Bosch blue coil ok in the car (been in there 3 years) if not which coil to purchase.

Car will start now but a couple of times after starting, I revved the engine to 2-3k and after a 10-20 seconds the engine died and the tach needle fell like a rock like the spark died.

Any help/advice is greatly appreciated.

http://forums.pelicanparts.com/uploa...1532363451.jpg

http://forums.pelicanparts.com/uploa...1532363451.jpg

dump the permadoom and blue coil.

at min put a MSD 6al and coil in there.

if interested I can post pics of how mine is mounted,..
I also mounted the coil right side up in the original location.

could be fuel related.
I would check fuel pressures
if no gauges at least check for power at the WUR.

alarm wont cause this,. the alarm disables it completely or it should. don't know much about the alarm.

I think it's ignition related but I'll check anything right now. Dumb question: where is the WUR located? Not sure I've looked at it before.

A note about when this no-idle situation (and hard starting) happened, I was half way through a 1 hour drive; lots of stop-n-go for the first 1/2 hour, then 3 miles of open highway and I went WOT through 2nd and 3rd gears. At the next traffic light turning red>green, I down shifted 3rd>2nd and the engine had died instead of idle. Popped the clutch in 2nd and it started and took off. No idle after that.

starting right back up is not "usually" ignition related. heat usually makes a marginal ignition system go bad and it will not work again until it cools. then the car runs fine until hot again.

you could also have an air leak. when cold the rich mixture covers it up, once hot and the mixture leans out it wont idle.
check the big Orings on the IC and check the up pipe form the turbo.

the WUR is located to the right of the TB, about its 2 oclock position. it has 2 fuel lines going to it and an electrical connector.

Alarm beeping usually means low battery.
Firing up again right after running awhile, usually indicates a weak battery that holds a charge for a short time frame, before bleeding off to a hard start situation.
Won't idle but runs at higher rpms, usually means low voltage to ignition at low rpm's.
Dancing tach usually means dying alternator.

For what it's worth...but that doesn't mean your ignition isn't acting up as well.

Mark

Whatever is happening with the engine, it seems to have happened in an instant. At one traffic light the engine was idling smoothly; three miles down the road at the next traffic light, the engine dies and will no longer idle.

One thing about that 3 miles is I went WOT throttle through 2nd and 3rd. I wonder if I could have blown off a fitting such that there's a massive air leak. My buddy said it sounds like an air leak but I couldn't tell with all the 911 engine noises. I sprayed carb cleaner on all the intake components except the turbo or any hoses under the engine tin and didn't suspect a leak.

you need to check/remove the IC orings.
if the IC is not bolted down it will blow off.

Thanks for the info. This alarm beeping was in direct coincidence to the positioning of the driver door. Wide open door and alarm goes off. Close it by 3 inches and alarm off. Open by 3 inches and alarm on.

I've measured the resistance of the alarm wire at the alarm and now for most of the door travel the resistance is infinite (open circuit). For wide-open door, it's zero resistance (short to ground). And somewhere in between I get a reading of about 4.7kohm. When the key is turned to on, I read 3.32kohm. These reading are correct for the resistors across the key contacts.

Well that's more info.
So the problem is most likely in the door or door jam, depending on where your door alarm sensor switch/contact is actually located. If the switch/contact is in the door, it could simply be a chafed wire short, caused by the movement of the wires connected to the door switch/contact as the door is being opened and closed.

Or it could be that your door sensor switch/contact is located on the door jam, very close to the door pivot point, so the actual working travel of the switch itself is the culprit.

Very doubtful the problem is in the alarm control itself.

Just a thought.

Mark

I’m terrible at diagnosing issues so I’ll save you from that.

But what I can tell you is be methodical in your approach to checking each system. I had similar problems and I tried a hodge lodge of fixes instead of being systematic and it took me months to find a clogged fuel injector was the issue.

I’d suggest starting with the easiest system. (Maybe checking for air leaks). Then move to the most likely (fuel or ignition) then if nothings been found check the last (fuel or ignition). But when you check a system focus on it and go from top to bottom. Don’t skip something thinking that’s not it.

I checked the hell out of my fuel system, but skipped checking the injectors because it hadn’t been listed as the possible cause. I even checked that each cylinder was getting even amounts of fuel but didn’t pull the injectors.

Do you ever get down towards Philly? I have a set of cis gauges I could lend you for a week or two. I wish I was a tad closer and could swing by and help.

Rich

It happened to me.....
On the way to a car show one early Saturday morning I pulled up at a light next to the wife in the Z4. Couldn't resist a little race....blew her away. When I took my foot off the gas the Porsche would no longer idle. Spent some time looking for the problem but couldn't find it. Left the Porsche in a parking lot and went on to the show with her (another 20 mi). Stopped on the way home to check it one more time before calling the tow truck. I had blown the hose off of the blow off valve causing a massive vacuum leak. Wasn't obvious because it is under a cover. 5 minute fix.:confused:

Thanks Rich,

It may get to that level of testing. If I get there, I may take you up on the offer.

This parallels my experience. Idle ok at one traffic light; after WOT in 2nd and 3rd, no idle at the next. I'll keep looking this weekend.

Found a vacuum leak at the inlet of the turbo. The crack in the hose where the screwdriver is inserted is about 2 inches long. Not sure if this is the culprit but it definitely needs replaced.

http://forums.pelicanparts.com/uploa...1532722437.jpg

Removed the coupling to the turbo. It had 2 large cracks in it. Not sure if this would cause loss of idle but it certainly could contribute to it.

I had to cut off the turbo coupler since the inlet tube doesn't move around that much.

Question: Is it possible to get the new coupler on w/o removing the engine? Doesn't seem to be that much clearance to install the coupler.


http://forums.pelicanparts.com/uploa...1532892137.jpg
http://forums.pelicanparts.com/uploa...1532892137.jpg
http://forums.pelicanparts.com/uploa...1532892137.jpg
http://forums.pelicanparts.com/uploa...1532892137.jpg
http://forums.pelicanparts.com/uploa...1532892137.jpg

[QUOTE=spoke;10124300]Removed the coupling to the turbo. It had 2 large cracks in it. Not sure if this would cause loss of idle but it certainly could contribute to it.

I had to cut off the turbo coupler since the inlet tube doesn't move around that much.

Question: Is it possible to get the new coupler on w/o removing the engine? Doesn't seem to be that much clearance to install the coupler.

Yes, you have to start by removing the elbow from the fuel meter allowing you to move the down pipe far enough to get the hose (coupler) in there. It is really tight but will go. Trim it to length before trying to install. I used something like this:
https://www.ebay.com/itm/2-75-4-PLY-TURBO-INTAKE-INTERCOOLER-PIPING-SILICONE-COUPLER-HOSE-T-CLAMP-BLUE/191378734610?hash=item2c8f0fbe12:g:3oAAAOSwonBaMYP m:sc:FedExHomeDelivery!79424!US!-1
http://forums.pelicanparts.com/uploa...1532949742.jpg

Got the new turbo hoses installed. Engine still having issues. It seems there is no spark at times.

Several times now the car has started right up and ran for a 1/2 minute or so then just shut off. The tach drops like a rock and the engine winds down to a stop.

I swapped coils with my 914 which uses the same Bosch blue coil and the same performance was observed. I'm ready to put in a new spark unit.

An MSD 6al and coil has been suggested. Where is the best place to purchase this spark unit and coil?

I see there's an MSD 6AL-2 with programmable distributor curve.

"The Programmable 6AL-2 lets you lock out the distributor and program a timing curve via a PC."

Since the vacuum advance can on the distributor is leaky and apparently not repairable or replaceable, would the AL-2 programming feature allow "bypassing" of the vacuum advance?

Looks like I can purchase a new distributor for $1800. Yikes!

just get the basic 6al. about 250.
I mounted mine on the left side above the relay panel. had to relocate a relay to the side but it looks better there.

you need to verify fuel pumps are running when it stops. I would remove the connector on the top rear of the AFM. this will run the pumps all the time with the key on.

check for spark

you need to swap the + and - from the dist that goes to the MSD. you can get a connector that will mate to the factory one. swap it there. that way if you want to plug in a bosch unit you still can. I carry my bosch as a spare.

Fuel pumps are running. If I short out the alarm the pumps will run as long as the key is in the ON position.

I've tried putting the Permatune in the freezer to see if heat is affecting it and when out it seems to run good then starts deteriorating. The tach will at times jump a bit, maybe a few 100 RPM or more. At times the car will stall where the tach drops like a rock and the engine dies.

Can I buy a schematic for my '86 930? I have a schematic named "Wiring Diagram Type 911 turbo Model 86 but I've found a few places where the schematic definitely does not match the car.

One thing I think I want to check is the power to the Permatune. It looks like it's powered through a relay called the "Delay Action Relay". I wonder if the power to the Permatune is steady or not.

trash the permadoom!!!

if you put it in the freezer and it runs good then gets worse, defiantly trash it.

put in an MSD.

The MSD 6AL comes in several flavors as well as the coil. The 6425 is offered here on Pelican. Which flavor of 6A and coil would you suggest.

Also, I still have the broken vacuum advance can on the distributor. Any advice on how to get this corrected?

Many thanks for your help.

MSD 6AL2 6421
MSD 6AL2 64213
MSD 6AL 6425 - Offered on Pelican
MSD 6AL 64253
MSD 6AL2 6530 - programmable
MSD 6AL2 65303 - programmable

Coils offered on Pelican:
8200
8202
8207 - Different shape than the can type
8203
8222

I think I have the 6425.
it has a dial for adjusting the rev limiter and it has an LED to show you are getting signal from dist. can be very helpful in times of stress.

the blaster 2 coil is what everyone suggests.

programmable will get around the broken can, but then you have to program it.
whats wrong, does it leak?

Another good thing about MSD ignition parts is almost every auto parts store in the USA has some of their stuff in stock or can get it in a day or two. That can be a big help if you're on the road traveling.

If you want to mount a MSD coil in the original place on the fan housing the epoxy filled MSD high vibration coil is probably best. It's black and the same size as the Bosch coil and you can peel the MSD sticker off if you don't like it.

Yes, the vacuum side with the larger hose from deep inside the intake is leaking. I can't provide enough vacuum with a brake vacuum pump to make the can advance the plate.

I'm leaning towards the programmable MSD 6AL-2 assuming I can't find a working vacuum advance and a new distributor is $1800. I think I'll post a WTB to see if there's any unused vacuum cans around.

Thanks. So what's the difference between the high vibration Blaster and the Blaster 2? I do plan on putting the coil in the original location on the fan housing.

Most ignition coils are filled with oil to cool the wire windings inside. An ignition coil is sort of like a type of step up transformer.
Mount one upside down on the fan shroud like Porsche did subjects it to vibration and heat cycles. An oil filled ignition coil may eventually start to slowly leak out the oil when it's mounted like that and then the engine stops when it fails. It happened to me. It was a Bosch coil made in Brazil that leaked out oil and burned out.
Epoxy filled coils are more durable in high vibration environments when mounted upside down and will probably tolerate the heat cycles for a longer time too.

If I remember correctly Permatune replacement coils are epoxy filled too.
Mount the coil(s) over on the left longitudinal or somewhere away from engine vibration and an oil filled coil will work and last just fine.

I was using the standard Bosch blue coil with the Permadoom. It's about 3 years old. I swapped it with the standard Bosch blue coil on my 914/4. The 914 is running great and the 930 is still having issues.

I'm checking the voltage at pins 31 and 15 at the CDI connector. First start today the engine fired right up, stumbled a bit, then idled at about 1500 RPM. I have the idle screw way out from the earlier loss of idle. Voltage was rock solid at 14.05V. Ran the engine for a couple of minutes and had no tach jumping.

Came out 1/2 hour later and started it up. Ran great but the voltage was now 11.8V. After 10-30 seconds, the voltage went to 14.05V but bounced around slightly 14.05-14.00 and the tach was jumping a very little bit like less than 100 RPM. Now I'm thinking the relay driving the CDI is suspect. On my schematic it's called Delayed Action Relay.

The bouncing voltage was measured with a voltmeter. I think I want to pull the DAR and inspect, as well as put my oscilloscope on these pins to see exactly what is happening.

Checked in the incoming voltage to the Permadoom today. Trying to make sure the failure to start/run and running poorly is the CDI and not other things.

I put the oscilloscope on the pin 15 (VBAT) to pin 31/1 (GND). The first attempt started then died. It is shown below. The baseline is the bottom line, volts/division is 2V, and time base is 2sec/division.

The voltage rises from zero to 12V as the key is turned on the the fuel pumps run for a second. As the engine is cranked, the voltage drops initially to about 6V then rises to about 8-10V as the engine is spinning and starting up.

As the engine started and ran ok for about 1 second, the voltage rises to almost 14V. The engine started chugging at a very low RPM and the voltage drops down to 12V or so. The hash observed are negative going spikes as the CDI fires. After about 4 seconds, the engine dies and the voltage is a steady 12V until I turned the key off and the Delayed Action Relay turns off.

http://forums.pelicanparts.com/uploa...1534632928.jpg

After a couple of unsuccessful tries to start the car, I sprayed a bit of starting fluid in the intake and the car started up and ran for several minutes.

Again after turning the key to ON for 1 second, I started the engine. The voltage drops instantaneously to about 6V then recovers to about 8-9V before the engine fires up. During the first second the engine stumbles then idles nicely at about 1500RPM. The idle screw is still screwed way out. The voltage at pin 15 is about 14V minus the negative spikes.

http://forums.pelicanparts.com/uploa...1534632928.jpg

Here's the voltage at pin 15 expanded to 5ms/division. In this picture, there are 3 pulses in 43.5ms. This comes out to 1380RPM. The voltage when the CDI fires drops to 12V. The little quick humps in between may be from the alternator as each phase of the stator is energized.

The voltage drops to 12V may not be all that bad although it's not reassuring to see this. This may be resistance in the wiring and the relay.

http://forums.pelicanparts.com/uploa...1534632928.jpg

After running for a few minutes, I turned off the engine and let it sit for 10 minutes while I did some other things. Came back and restarted the engine. Started right up but after a minute the tach started jumping a bit then the engine started struggling and eventually stalled.

I was able to catch some of the last few CDI firings. This trace is when the engine was just about stalling. Notice how several of the firings are missing. The engine won't run well if the CDI is not firing the spark plugs.

This testing shows the supply voltage isn't all that bad and the CDI starts having significant trouble firing the plugs.

http://forums.pelicanparts.com/uploa...1534632928.jpg

After the engine stalled, I tried starting it right back up. Now the time base is set to 2sec/division. The engine starts up then begins to struggle and eventually dies.

After running for about 1 second, the engine starts to die, then recovers for another second but then really struggles and eventually stalls.

http://forums.pelicanparts.com/uploa...1534632928.jpg

The next test I'll do is to monitor the signal from the distributor to make sure it is always firing. This way I can be sure the CDI is at fault. For this test I'll use 2 channels so I can see both the distributor signal and the supply voltage.

Spoke, stick one of our CDI+ units on it with a Bosch black coil. Plug and play. Multi spark to 10000 RPM, fires 3 times faster than MSD. Made by 911 folks specifically for the 911.

You won’t be disappointed!

Being the spert in this area I thought you would help Spoke analyze his info.......not just try to sell your product.

He's already on it, either green wire or CDI box.

As was pointed out earlier in the thread he has the wrong coil. He needs a Bosch black coil and most likely an ignition box

What is wrong with recommending my own? I designed it as an enthusiast in the first place. Yes I make some $ out of it just like Spoke makes $ out of LED conversions.

Then advance the timing a hair to compensate.

When I've watched in car video during Nascar races I've seen MSD ignition units on the dashboard over on the right side. If it's good enough for them it's good enough for street cars and they have good phone and email support.

I'm ok with your recommendations. Like most owners with Porsche troubles, I'm happy folks with more knowledge than I are chiming in to help out.

I checked out your products and they look very well designed. Also checked out the video wrt performance. Very thorough work.

One question about your setup: As observed in my measurements there is considerable resistance between the voltage source and the CDI. You use a lab supply in your bench testing. Do you have resistance in series between the supply and the CDI to simulate the resistance observed in the vehicle?

Many folks recommend the MSD 6AL CDI. How does the 6AL compare to your CDI?

Looked at the CDI input voltage as before and now I'm monitoring the signal on pin 7 from the distributor on channel 2.

In the first trace the signal on channel 2 from the distributor peaks at just less than 20V and bottoms out at -10V. Engine running steady, no jumping on the tach.

Then like a switch was thrown, the engine stumbled at bit and the idle slowed down as shown in the 2nd trace. Notice how the distributor signal dropped a lot; hardly a signal now. Within 20 seconds the engine stalled.

After this I tried removing the CDI and measure the signal from the distributor as Johnny H suggested. Now I don't see any signal at all.

http://forums.pelicanparts.com/uploa...1534705735.jpg

http://forums.pelicanparts.com/uploa...1534705735.jpg

Have you checked the resistance/ohms of the distributor internal coil when it runs and then when it doesn't? Also " I sprayed a bit of starting fluid in the intake and the car started up and ran for several minutes" makes me wonder about it being ignition related. When it dies does it always start with starting fluid?

^. Where are you measuring this ‘considerable resistance’?