Will buy pizza, beer, strippers (joke) to get a fellow D owner to come out to tinker

[artisticent]

Hi all,

I live in Moorpark, ventura county. I am in the process of removing the interior on my D to get it all upholstered but there are some wiring repairs, general learning on my part that I really need. My car runs very well except I think now that I have removed some interior parts and disconnected a few things, the engine fluctuates in idle. There is also something that is causing a drain on the battery. When the car was at DMC last they confirmed the charging system is good but there is a drain which will cause the battery to die in a week or so. Anyway Id love a visit and some help. If this is at all possible on a weekend on whenever is convenient I would be so very grateful. Please contact me anytime.
Thank you
Nathan
818 203 7471

[Jonathan]

Do you park it indoors somewhere that you could turn off the garage lights and get the room dark enough to then look over the car to see if any lights are staying on while it is sitting there?

Sounds to me like maybe your door lights are staying on or perhaps your glovebox light.

For the fluctuating idle, if it's related to removing interior parts, maybe you dislodged a vacuum line, like the one going to the HVAC mode control switch behind the dash?

[vps3922]

Darn, no strippers? I am out! :biggrin:

Back to topic: I agree with Jonathan. These door switches can be a pain in the backside. I recently installed a new door seal and the plunger switch would not connect properly. I hope that the seal is setteling soon so the switch is working again. This would keep my dome lights (easy to switch off) and door lights on (not so easy unless you disconnect the plunger switch and have no lights come on at all). I guess that you do not have LEDs installed. My friend Dave G. (sdg3922) had his LED lights on for a weekend before I stumpbled into his garage, picking up some of my parts from the restoration, asking him why they are on via text message. He totally forgot about them, but they were still bright and shining.
But that would not solve your problem. You have a power drain somewhere. You could also check if there is a life cable among the ones floating around. Not sure if this idea floats as it would probably trigger a fuse to shorten.

[sdg3205]

Nathan,

Check the glove box light as well.
Try unplugging your door lock module. They will drain your battery in 2 weeks.

Also - don't trust your alternator. Put a meter across the battery at idle and be sure you're getting a little over 14v. I've seen new and rebuilt alternators fail within days.

[vps3922]

Darn, no strippers? I am out! :biggrin:

Back to topic: I agree with Jonathan. These door switches can be a pain in the backside. I recently installed a new door seal and the plunger switch would not connect properly. I hope that the seal is setteling soon so the switch is working again. This would keep my dome lights (easy to switch off) and door lights on (not so easy unless you disconnect the plunger switch and have no lights come on at all). I guess that you do not have LEDs installed. My friend Dave G. (sdg3922) had his LED lights on for a weekend before I stumpbled into his garage, picking up some of my parts from the restoration, asking him why they are on via text message. He totally forgot about them, but they were still bright and shining.
But that would not solve your problem. You have a power drain somewhere. You could also check if there is a life cable among the ones floating around. Not sure if this idea floats as it would probably trigger a fuse to shorten.

Darn, I need a coffee: it is not sdg3922 but sdg3205. I just made Dave the owner of my car. :wave2:

Anywho! What he said! I had a rebuilt Ducellier alternator and we found out that the voltage would first be around 14V, then fluctuate between 14V and 17V when getting warmer and jump to 17-18V when warm. We pulled the alternator and I replaced it with a Motorola from DMC NW. The Ducellier has a defective voltage regulator. That can screw up your system as well and cause damage in various areas. Toby Peterson from DMC NW told me some stories about owners with the same issue that nearly fried several parts of their car and had weird electrical issues.

[artisticent]

Great advice guys.

In fact the car is in my garage with 24/7 fluorescent lighting so I guess I wouldn't have noticed any light but it makes perfect sense to check. Im assuming the alternator is good as DMC Garden Grove checked that not that long ago in a general motor "go over" but I suppose that is just an assumption. I just took the battery to Auto Zone and they read the battery as 6v lol.
I will try turning off the power to the lights later to check for light.
In the old days I would check a short by connecting a volt meter to the battery and remove one fuse at a time to record the results with one circuit out. I wonder if that would be a good way to check for the main source of battery drain?

[Rich]

I wonder if that would be a good way to check for the main source of battery drain?

You make a fuse jumper and measure the current in each fused circuit.

Fuse jumper pair of wires with a spade lug on one end and a banana plug on the other. You wire those up to each numbered fuse holder with the banana plugs going to a multimeter set to measure DC current (amps), then work your way, circuit by circuit, up and down the fuse block.

That covers everything except the loads that aren't fused.

Before you do all that work be sure to remember Dave's advice to pull the connector off of the door lock module and see how much longer your battery lasts. You probably need a new battery (should last about 2-3 weeks between starts). Eventually you will want to consider getting DMCH's solid state door lock module, the one that doesn't drain the battery.

[Ron]

In the old days I would check a short by connecting a volt meter to the battery and remove one fuse at a time to record the results with one circuit out. I wonder if that would be a good way to check for the main source of battery drain?Try the same thing but put a small bulb (eg tail or brake light) in series with the battery and look for it to burn or glow. Note a large drain would blow the bulb and you have to disconnect the things others have mentioned first...

[artisticent]

Well after being out there this evening, there aren't any rogue lights on in the car but ill try the suggestions below. My bettery is almost new and took a full charge no problem. Ill try disconnecting the door lock module (where ever that is lol) Yes the solid state sounds like the way to go. Sorting out the wiring behind the console is interesting. What a mess from owners over the years. Cant wait to clean it all up as I go.

Thanks
Again

[artisticent]

Oh and Johnathan, in regards to the vacuum line check, I have a small plastic open vacuum tube coming from the engine over the center console that stops by the armrest and i have a 3way intersection behind the stereo that has a 12" piece of vacuum line that isn't connected. and so the search begins lol.

[NightFlyer]

Oh and Johnathan, in regards to the vacuum line check, I have a small plastic open vacuum tube coming from the engine over the center console that stops by the armrest and i have a 3way intersection behind the stereo that has a 12" piece of vacuum line that isn't connected. and so the search begins lol.

The small plastic one that runs along the center console is the vacuum line for the heater control valve (hot water shut-off). It butt splices into a rubber vacuum hose that hooks up to the mode switch octopus on that end.

Sounds like you have your work cut out for you - best luck :thumbup:

[Jonathan]

The small plastic one that runs along the center console is the vacuum line for the heater control valve (hot water shut-off). It butt splices into a rubber vacuum hose that hooks up to the mode switch octopus on that end.

Sounds like you have your work cut out for you - best luck :thumbup:

Josh, would a vacuum hose disconnected or loose up towards the HVAC mode control switch or centre console be included in the places you could have a vacuum leak and affect your idle? I wasn't sure if the HVAC vacuum lines originated somewhere that would or wouldn't affect engine idle, or whether it came off before or after the control of that vacuum to be considered "unmetered."

Like the hissing some of us hear behind the mode switch. If a car had this bad enough, would it affect your idle? You would think this is a pretty small amount of air flow, but it would still contribute.

[alexwolf1216]

Josh, would a vacuum hose disconnected or loose up towards the HVAC mode control switch or centre console be included in the places you could have a vacuum leak and affect your idle? I wasn't sure if the HVAC vacuum lines originated somewhere that would or wouldn't affect engine idle, or whether it came off before or after the control of that vacuum to be considered "unmetered."

Like the hissing some of us hear behind the mode switch. If a car had this bad enough, would it affect your idle? You would think this is a pretty small amount of air flow, but it would still contribute.

I just charged up my AC, and after it started working my idle is rough. It was rock solid prior to the AC repair. Now it bounces around 750-950. The needle is constantly moving.

[artisticent]

Ok so a little update. I bought some vacuum tube and reconnected the small plastic hose to the 3way vacuum connector behind the stereo. It didnt make any difference to the idle. HOWEVER when I pulled the vacuum plug connector away from the fan control knob causing me to hear the vacuum leaking out of that connector, the idle leveled out and stayed almost perfect. Obviously I can leave this disconnected. Does this help with trouble shooting my rough idle?

[Jonathan]

Making progress, good.

Which connector did you mean, by the way? Are you saying when you move around the connections on the back of the HVAC mode control switch the idle got better?

At the very least, it sounds like this is where your focus might need to be (barring anything odd and coincidental that was happening at the same time). You may need to gain access to that mode control switch behind the console and ensure it's got all the vacuum hose lines connected well and the switch itself is all nice and lubed up internally.

We'll see if there is a how-to on the switch, either rebuilding it or at least showing how it all connects...

EDIT: http://dmctalk.org/showthread.php?9758-AC-blowing-only-on-0

Videos in this thread. Caveat emptor on those... :) I don't see that they show the vacuum hose connections unfortunately though but you can see the inside of the switch and how it would get rebuilt.

[artisticent]

Hi Johnnathan,

Thanks for the response, its not so much when i jiggle or move around the mode control switch but when I actually disconnect it completely the car begins to idle so much better. I can hear the main vacuum line feed hissing and when I turn the car off I can hear the vacuum release for a second or two. It just seems odd that with such a huge vacuum leak as the mode control switch plug being disconnected, the car would really be struggling to run. Instead it runs better than to connect the plug where it belongs. Does the car have a stabilizer of some sort that is making the adjustment due to detecting such a big vacuum leak ? Hmmmm

[Jonathan]

I'm not quite sure myself, but that's kind of why I mentioned it. I'm chasing my own idle hunt issue and think it could be related to a vacuum or air leak.

I'm not aware of any sort of stabilizer that would detect the vacuum leak and adjust. Mostly it seems if there is any kind of vacuum leak, it will compete with the engine and it's needs and if either aren't consistent, you get this hunting. A couple operational things change in the car as the temperature warms up, but then so too can the size or existence of the vacuum leak. I think that is what makes them hard to find. Inconsistent or intermittent.

The part about them being described as unmetered is where the leak is. If you are leaking air (in or out) prior to it going through the throttle plates, I don't think it has that big or bad of an effect. But if there is a leak after this point, then it can't be compensated for because the controlling piece is upstream. That's why I think you hear mention of the gaskets on the W pipe or that rubber/NLA part on the connection just before that section.

I don't honestly know how much a vacuum leak up at the HVAC mode control area could affect an engine idle hunt. I was hoping someone that did know for sure might chime in. There are plenty of things we can do to the cars which seem like they affected something, but were really just coincidental and actually had no impact on the problem we're seeing but we get fooled into thinking they do. The vacuum lines up at the console might be something like that. Or at least plugging it in versus not. Sometimes we've changed something else in doing so and don't realize it.

[thomasuncles]

I'll come out with my DeLoran just to hang out ;) I'm no help mechanically at all, but send me a PM whenever you pick a day and I'll join you all for the day. ;)

Thomas



Hi all,

I live in Moorpark, ventura county. I am in the process of removing the interior on my D to get it all upholstered but there are some wiring repairs, general learning on my part that I really need. My car runs very well except I think now that I have removed some interior parts and disconnected a few things, the engine fluctuates in idle. There is also something that is causing a drain on the battery. When the car was at DMC last they confirmed the charging system is good but there is a drain which will cause the battery to die in a week or so. Anyway Id love a visit and some help. If this is at all possible on a weekend on whenever is convenient I would be so very grateful. Please contact me anytime.
Thank you
Nathan
818 203 7471

[artisticent]

Hi Thomas,

Sounds great and thanks for the reply. Because I am getting in to some console/dash redesign, Id love to see your D in its complete state. I am well in to ripping my dash apart at this point. Hows this weekend for you? sunday perhaps?
818 203 7471 call anytime
Nathan

[NightFlyer]

Josh, would a vacuum hose disconnected or loose up towards the HVAC mode control switch or centre console be included in the places you could have a vacuum leak and affect your idle? I wasn't sure if the HVAC vacuum lines originated somewhere that would or wouldn't affect engine idle, or whether it came off before or after the control of that vacuum to be considered "unmetered."

Like the hissing some of us hear behind the mode switch. If a car had this bad enough, would it affect your idle? You would think this is a pretty small amount of air flow, but it would still contribute.

Sorry - I must have missed this previously.

Long story short, yes a leak on any of the vacuum operated systems on the car could be significant enough to alter/effect the operation of the engine, as un-metered air would be introduced into the combustion process and thereby cause a lean running condition. The lambda system will effectively counter the effects of such a small leak once it engages, provide that it's working properly of course.

Here's a little something that I put together regarding the vacuum operated systems on our cars:

http://www.dmctoday.com/showthread.php?892-Vacuum-Systems-on-a-Stock-OEM-Engine&p=17615&viewfull=1#post17615

[NightFlyer]

I just charged up my AC, and after it started working my idle is rough. It was rock solid prior to the AC repair. Now it bounces around 750-950. The needle is constantly moving.

Did you ever get this resolved, or are you still idle hunting?

[artisticent]

Well ironically it idles almost perfectly with the selector dial (that has all the vacuum tubes) disconnected in the center console. When it's connected it runs horribly. As if it's gonna die. but I love your diagrams. I'll check it all out tomorrow hopefully

[NightFlyer]

Vacuum for the HVAC controls is tapped off the passenger side intake runner and is shared with the brake power booster via a 'T' fitting/connector.

The fact that your car idles better with a vacuum leak being present suggests that there may be an issue with the idle air (CIS) system, which includes the idle speed motor (ISM), the idle ecu, and the idle micro-switch. It's also possible that your CO/AFR is mis-adjusted and is running the engine rich, which is why the introduction of unmetered air to the combustion process is smoothing it out.

I'd start by making sure the the CO/AFR is properly adjusted and go from there in diagnosing the CIS if necessary.

Best luck :thumbup:

[artisticent]

The frustrating part is that dmc in garden grove did quite a bit of engine work and I would've thought that would be checked. Which tells me the problem would be inside. Maybe even something I may have accidentally disconnected. I've only really checked the vacuum lines at the center console area. where is the CO/AFR?

[alexwolf1216]

Did you ever get this resolved, or are you still idle hunting?

Its still rough, a little hunt, but now it pegged at 1500 with the cooling issue.....I guess the car, after sitting all these years, needs to get its crap out of the system ha.

[NightFlyer]

Its still rough, a little hunt, but now it pegged at 1500 with the cooling issue.....I guess the car, after sitting all these years, needs to get its crap out of the system ha.

Are you starting it and letting it idle with the A/C on or off?

IMHO, not good to start a DeLorean with any of the additional accessories (radio, A/C, headlights, HVAC blower motor, etc) in the on position, as that's really going to strain the electrical system (which wasn't the pinnacle of automotive electrical engineering - remember, we're talking about Lucas here). Always turn off all accessories before turning the engine off and make sure that they're off before attempting to start the car. This isn't like a new car.

That said, if you're starting and idling with all accessories off, are you still idling at 1500rpm. Is the idle the same even after the engine warms up, or is it different after a warm up vs from starting and idling cold?

[alexwolf1216]

Well I start the car with the ac on, it seems to start better....but ill stop doing that. The idle started with the nonsense yesterday.....so prob a different issue.its only when it's really warm, over normal operating temp.

OP, if anyone takes you up on the beer/food/stripper idea send them down my way. I have a guest room. Thinking about kidnapping someone smart for a few days

[NightFlyer]

The frustrating part is that dmc in garden grove did quite a bit of engine work and I would've thought that would be checked. Which tells me the problem would be inside. Maybe even something I may have accidentally disconnected. I've only really checked the vacuum lines at the center console area. where is the CO/AFR?

The CO/AFR (carbon monoxide / air-fuel ratio) adjustment that I'm referencing is located in a hole on the air mixture unit between the air metering plate housing and the fuel distributor. If it was never adjusted since leaving the factory in Dunmurry, then it may still have a protective anti-tamper plug over it (that was required by federal emissions regulations at the time). If it has been since adjusted, then there will be some sort of removable plug in the hole (golf tee, rubber plug on a metal fish eye ended handle, etc), as the hole would otherwise represent an unmetered air/vacuum leak.

To set the CO/AFR properly, an exhaust gas analyzer is necessary. But, as most tend not to have easy access to such equipment, most people tend to adjust by reading the dwell of the signal from the O2 sensor or the duty cycle of the frequency valve using a multi-meter. To adjust this way, the lambda system must be in functional condition/operation.

Here's a good thread which provides more information on this adjustment:

http://dmctalk.org/showthread.php?5760-Adjusting-CO-With-A-Dwell-Meter

If more information is required, let us know.

Best luck :thumbup:

[NightFlyer]

Well I start the car with the ac on, it seems to start better....but ill stop doing that. The idle started with the nonsense yesterday.....so prob a different issue.its only when it's really warm, over normal operating temp.

That's interesting that you say that it seems to start better - how so? Less cranking before it catches?

I'm trying to think of why that would be and a couple things come to mind - when the HVAC mode switch is otherwise set to off, you may be experiencing a vacuum leak, which would suggest a problem with the rubber maze/diaphragm on the mode switch itself. Another possibility is that idle computer is instantly going into running an enriched fuel increased rpm idle mode (to compensate for the extra load on the engine of the compressor running), which suggests that you may otherwise have an issue somewhere in the CIS (idle speed) system.

Starting with the A/C on puts a lot strain on both the fuel and electrical systems, which is really going to be taxing the electrical system - didn't you say that your alternator's regulator tested bad, requiring replacement of the alternator? Starting with accessories on also taxes the battery, deeply discharging it (more than usual), as it has to provide instant power to the cooling fans (which are one of the highest electrical draw components on the car, especially if they're the stock/OEM units, and draw a lot of power upon initial startup (activation energy)). When starting, the starter motor is also sucking a lot of power from the battery to operate. It's best to stagger and separate these draws out as much as possible (that's what gave birth to electrical system modifications such as the Fanzilla, etc).

Remember - you can either adapt the car to your habits/expectations (which can get VERY expensive), or you can adapt your habits around / to work with the known quirks of the car (which is what I prefer to do, but I'm admittedly a cheap ass, but I also like preserving the originality of my car as opposed to updating/upgrading/modifying things) :smile:

[alexwolf1216]

Touché. Will start with accessories off.

[NightFlyer]

Touché. Will start with accessories off.

Good man - your alternator, battery, and wiring will all thank you for it :thumbup:

[alexwolf1216]

Replacing alternator hopefully this weekend

[NightFlyer]

Replacing alternator hopefully this weekend

While doing that, have the battery tested and replace if necessary, otherwise trickle charge it full outside the car before reinstalling.