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'79 OUTLAW
 
Join Date: Apr 2018
Location: Toronto
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Trouble shooting my Cold Idle Issues...

Hi everyone,

Day 02 with my '79 SC and we're getting to know one another well. Other than finding my way around her here is my first issue:

Cold start she fires up fine, idles to about 2000rpm for a couple of minutes and off we go. First stop sign she dies. Fire her up again, off we go. Second stop sign she dies again. After about 5-10mins there is no problem and idles nicely at around 950rpm when stopped.

I've been reading through the forums and looks like I have a CIS issue on my hands (whatever that is.... learning as I go). So I have lots of reading ahead of me and Pelican and its community are proving absolutely awesome in all your help.

I understand a first check would be my fuel pressure so time to invest in some gauges. Before I do so could you guys let me know if these will do the job:

01: http://a.co/659QbQ0
02: http://a.co/9s6V5fQ
03: http://a.co/bbM9PSO

thanks!
dK

Last edited by thefaculty; 05-21-2018 at 03:24 PM..
Old 05-16-2018, 06:23 PM
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Quote:
Day 02 with my '79 SC
Sheesh, what's happened to this board? Pics man, pics! Everyone likes pictures...

Seem to recall I bought the CIS tester from our host, long time ago, after running a CIS car for years: https://www.pelicanparts.com/More_Info/TOLSGT33865.htm?pn=TOL-SGT-33865&SVSVSI=787

Used it precisely once and sold it on a few years later...

Pretty likely any of the ones you linked would work too. You really don't need much; just adapters to connect the gauge to your fittings, a bypass valve to read the system pressure, then check the cold and hot pressures as controlled by the WUR.

But you may not even need one, because it sounds like it runs fine once warm. Which points to the warmup cycle on the WUR (Warm Up Regulator - a complete misnomer, because that's only part of what it does) not doing what it should.

This is a little alu box with a little tower on top at one end with some fuel banjos bolted on it, located on top of the motor (try tracing fuel lines from the fuel distributor, fuel filter/accumulator that don't go to the injectors - you'll find it). It also has an electrical connector.

Check is that the plug side of the connector is powered with the ignition on. If it isn't, that could be the problem. Motor runs fine after a while because the WUR leeches the heat from the motor block itself. But the block will take (much) longer to impart any heat to the WUR than the internal heating coil would do it. And all the time the WUR is colder than it should be, the mixture isn't correct (CCP too low == too rich).

If the plug is powered with ignition on, use a multi-meter to check the resistance across the pins in the socket; the internal heater coil wrapped around the bi-metallic strip that adjusts the mixture can go out of spec - or break completely. Open or shorted is bad - something like 28-30 ohms is probably ball-park/fine, but there's a few CIS gurus who can tell you the exact correct spec if you provide the WUR and engine type #

I'd start there; easy to check and seems to fit the symptoms.

2000 also sounds kind of obnoxiously high for cold idle; but that may be correct for an SC. At least it drops when hot, so you know the AAR (auxiliary air regulator) seems to be working fine.

Good luck!
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Old 05-17-2018, 12:37 AM
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In this photo is the CIS pressure test kit that I purchased - as recommended by a CIS guru - Tony. It is S & G Tool Aid #33800. You can find it for about $90 US

As well are publications relating to CIS that I found.

BTW, 2000 RPM on start-up is what my '79SC typically reaches



Jason
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Last edited by LIRS6; 05-17-2018 at 05:15 AM..
Old 05-17-2018, 05:10 AM
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'79 OUTLAW
 
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Brilliant! Thank you both. Yes - sorry for the pictures posting I actually did post pics of all 3 but I am finding the forums do not always work in displaying them so far. I'm following guides but no luck on this post I'm afraid. Thanks so much for the info though. I'll order one of your recon for sure instead of chancing it.

Cheers guys!!
dK
Old 05-17-2018, 07:07 AM
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'79 OUTLAW
 
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Quote:
Originally Posted by spuggy View Post
This is a little alu box with a little tower on top at one end with some fuel banjos bolted on it, located on top of the motor (try tracing fuel lines from the fuel distributor, fuel filter/accumulator that don't go to the injectors - you'll find it). It also has an electrical connector.

Check is that the plug side of the connector is powered with the ignition on. If it isn't, that could be the problem. Motor runs fine after a while because the WUR leeches the heat from the motor block itself. But the block will take (much) longer to impart any heat to the WUR than the internal heating coil would do it. And all the time the WUR is colder than it should be, the mixture isn't correct (CCP too low == too rich).

If the plug is powered with ignition on, use a multi-meter to check the resistance across the pins in the socket; the internal heater coil wrapped around the bi-metallic strip that adjusts the mixture can go out of spec - or break completely. Open or shorted is bad - something like 28-30 ohms is probably ball-park/fine, but there's a few CIS gurus who can tell you the exact correct spec if you provide the WUR and engine type #

I'd start there; easy to check and seems to fit the symptoms.

2000 also sounds kind of obnoxiously high for cold idle; but that may be correct for an SC. At least it drops when hot, so you know the AAR (auxiliary air regulator) seems to be working fine.

Good luck!
Thanks so much for this - I just had some time to read it in full and I will follow all your advice here and report back. Really grateful to you! Thanks Spuggy!
Old 05-17-2018, 12:43 PM
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I have access to the tech instruction book electronically.

The Probst book is a profoundly powerful learning tool.
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Old 05-17-2018, 01:01 PM
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I have the exact same gauges as pictured by LIRS6. I've owned 3 CIS cars and the gauges work great
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Old 05-17-2018, 06:20 PM
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These guages:

Quote:
Originally Posted by thefaculty View Post
Before I do so could you guys let me know if these will do the job:

01: http://a.co/659QbQ0
02: http://a.co/9s6V5fQ
03: http://a.co/bbM9PSO

thanks!
dK
I have the set in the first link. Everything you need is included with that set, as well as a lot of stuff you don't need. It has connectors for all types of cars, but you only need two of them - one to connect to the fuel distributor and one to connect to the WUR.

The photos below show the connectors needed. You'll need to use either the original crush washers or the plastic ones included in the kit. And check carefully for leaks, both while testing and especially when you connect things back up when you're done.






Old 05-18-2018, 08:45 AM
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'79 OUTLAW
 
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Quote:
Originally Posted by spuggy View Post
Check is that the plug side of the connector is powered with the ignition on.
Hi Spuggy - I feel very dumb asking this but how would I check that the plug side of the connector is powered. I have found the WUR and can easily see the electrical plug but I cannot figure out how to disconnect it.

This comes with a thousand thanks!!
Old 05-18-2018, 02:13 PM
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The Mighty Pieholio
 
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Quote:
Originally Posted by thefaculty View Post
...................and can easily see the electrical plug but I cannot figure out how to disconnect it.
I don't know if there is a simple way to dislodge the c-clip wire thingie in with your fingers.

I have always used a scriber or a scriber with a 90 degree bend on the tip to pull the clip off.

It will fly so have your other hand there or a rag stuffed around it to capture when it pops out.

I'll bet I have been doing it wrong for decades. Let others comment before performing procedure.
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Old 05-18-2018, 02:26 PM
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Quote:
Originally Posted by thefaculty View Post
Brilliant! Thank you both. Yes - sorry for the pictures posting I actually did post pics of all 3 but I am finding the forums do not always work in displaying them so far. I'm following guides but no luck on this post I'm afraid. Thanks so much for the info though. I'll order one of your recon for sure instead of chancing it.

Cheers guys!!
dK
No, no, no....

We want pictures of THE CAR!!!!!

As some would say, “THIS...”
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Old 05-18-2018, 02:32 PM
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'79 OUTLAW
 
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Lets try this:::
Old 05-18-2018, 02:42 PM
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Quote:
Originally Posted by Bob Kontak View Post
It will fly so have your other hand there or a rag stuffed around it to capture when it pops out.
Thanks Bob. That's what I was worried about. I can get the clip off I think but I was actually more worried about how I would get it back on again once off. I'm always trying to remember not only do I have to take something apart but I also need to return it to it's original (if not improved) state!!
Old 05-18-2018, 02:44 PM
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Quote:
Originally Posted by thefaculty View Post
Thanks Bob. That's what I was worried about. I can get the clip off I think but I was actually more worried about how I would get it back on again once off. I'm always trying to remember not only do I have to take something apart but I also need to return it to it's original (if not improved) state!!
Put the clip back on when it's off the WUR. It will snap back on with pressure.
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Old 05-18-2018, 02:57 PM
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'79 OUTLAW
 
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Hey guys reporting back on power to the WUR. I finally managed to get the electrical plug off and a multi-meter to it:

• Ignition off: 0V
• Ignition on: 11.28V
• Engine running: 11.28V

Then check resistance at the terminals. I hope I did this correctly, never done it before: switched meter to Ohms, touched positive and negative to the terminal ON the WUR (not the Wire). The numbers danced around rather erratically (is that to be expected?) and then settle on 28Ohms. Can we deduce from this that the WUR is good and the problem lies elsewhere?

Cold idle issue still remains. Starts perfectly, idles well until we actually go somewhere, then rpms drop and engine dies at first stop sign. This repeats for about 8-10minutes after which we are good to go all day long.

With engine bay open doing this I noticed a long high-pitched beep coming from something on the left of the engine, is that usual? It is there constantly and did not stop.

What would be the next test? Get a set of CIS gauges and check pressures?

Thanks so much for any advice you are able to impart! The car so far runs perfectly aside from this (and me occasionally stumbling around 5th gear!).
Old 05-21-2018, 03:12 PM
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Quote:
Originally Posted by thefaculty View Post
Hey guys reporting back on power to the WUR. I finally managed to get the electrical plug off and a multi-meter to it:

• Ignition off: 0V
• Ignition on: 11.28V
• Engine running: 11.28V
That battery voltage would lead me to check voltage across the battery terminals themselves and work backwards. It's almost certainly not your warmup problem, but it's low.

Quote:
Originally Posted by thefaculty View Post
Then check resistance at the terminals. I hope I did this correctly, never done it before: switched meter to Ohms, touched positive and negative to the terminal ON the WUR (not the Wire). The numbers danced around rather erratically (is that to be expected?)
Entirely normal for an auto-ranging DMM, especially on a very sensitive scale and/or when the connectors are slightly oxidized or grubby.

Quote:
Originally Posted by thefaculty View Post
and then settle on 28Ohms. Can we deduce from this that the WUR is good and the problem lies elsewhere?
Sounds like the heater coil is intact and should be powered.

Next i'd say you need to find your motor type #, the # on the WUR and the # on the AAR. Without that information, no-one can look them up to find out a) if they were intended to work together and b) what the correct specs are for WUR control pressure(s).

Quote:
Originally Posted by thefaculty View Post
Starts perfectly, idles well until we actually go somewhere, then rpms drop and engine dies at first stop sign.
Wait, the high idle stops as soon as you start driving it - e.g. the first stop sign it stalls?

That's weird.

Quote:
Originally Posted by thefaculty View Post
With engine bay open doing this I noticed a long high-pitched beep coming from something on the left of the engine, is that usual? It is there constantly and did not stop.
That's the CDI (capacitive discharge ignition) unit - it sounds like a old school camera flash charging, and for the same reason... The noise doesn't necessarily mean it's working properly, but it certainly isn't if you can't hear it...
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Last edited by spuggy; 05-21-2018 at 11:51 PM..
Old 05-21-2018, 11:47 PM
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Quote:
Originally Posted by spuggy View Post
That battery voltage would lead me to check voltage across the battery terminals themselves and work backwards. It's almost certainly not your warmup problem, but it's low.

Wait, the high idle stops as soon as you start driving it - e.g. the first stop sign it stalls?
That's weird.
Brilliant - thanks again spugggy.
No, sorry I may not have been clear in my explanation. From cold the car idles high (2000rpm) for a couple of minutes and then lowers on it's own to around 950rpm. It will sit there quite happily until we go anywhere. We drive away but it is then at the first stop sign, we are in neutral, that the rpms drop and the car dies. This continues for 8-10mins each time and then we are good to go for the day with no more issues unless we stop for long enough for the car to cool again.
And sorry, what should the voltage read at the battery? 12V?
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Old 05-22-2018, 03:21 AM
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Quote:
Originally Posted by thefaculty View Post
Brilliant - thanks again spugggy.
No, sorry I may not have been clear in my explanation. From cold the car idles high (2000rpm) for a couple of minutes and then lowers on it's own to around 950rpm. It will sit there quite happily until we go anywhere. We drive away but it is then at the first stop sign, we are in neutral, that the rpms drop and the car dies. This continues for 8-10mins each time and then we are good to go for the day with no more issues unless we stop for long enough for the car to cool again.
And sorry, what should the voltage read at the battery? 12V?
I have the same issue, will do pressure tests when I have a chance. I suspect WUR.
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Old 05-22-2018, 05:13 AM
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Quote:
Originally Posted by LIRS6 View Post
I have the same issue, will do pressure tests when I have a chance. I suspect WUR.
Keep us posted - I'd be very curious to know what you find.
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Old 05-22-2018, 07:02 AM
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Quote:
Originally Posted by thefaculty View Post
Brilliant - thanks again spugggy.
No, sorry I may not have been clear in my explanation. From cold the car idles high (2000rpm) for a couple of minutes and then lowers on it's own to around 950rpm. It will sit there quite happily until we go anywhere. We drive away but it is then at the first stop sign, we are in neutral, that the rpms drop and the car dies. This continues for 8-10mins each time and then we are good to go for the day with no more issues unless we stop for long enough for the car to cool again.
Most AARs close up after 5, 7-8 minutes, depending on type - they're normally matched to the warmup cycle on the WUR.

2 minutes seems kind of short. AAR type should match the WUR type, or the warmup curve will be mis-matched.

You need the motor, WUR and AAR type to ensure the correct complementary parts are fitted and then to look up the specs for those parts and check your units against spec.

It could also be something else entirely.

Quote:
Originally Posted by thefaculty View Post
And sorry, what should the voltage read at the battery? 12V?
12.5V across battery posts, car not running. Old batteries can read lower but still work fine - sometimes for years, and usually right up until they don't...

Right on 14V for car running.
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Old 05-22-2018, 10:20 AM
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