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> High idle 2.0 djet, Been working on it for a little
Brasil914
post Mar 7 2017, 08:02 AM
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Hey all my name is John. I have been using 914 as a resource for a while but just registered (I have questions). So I have a 73 2.0 hand me down from dad. And I have idle issues. History: 86 dad snapped spark plug. Got what he could out of it and then tried to vacuum the head thru the spark hole. Was worried that not every thing was out so never started it again, and forgot to drain the tank. It sat in garage and storage until 2008 when he gave it to me. First thing I did was run a borescope in the cylinder , couldn't see jack. So dropped the motor pulled the head and the cylinder was clean as a whistle. Did some work over about three years sourcing parts and such. And got it to run in 2010. Then moved to SC. Got it here six months later and started on it some more. No I have had down time from work and have started tinkering again after 2 years. I have replaced all hoses,injectors and seals, yesterday I opened and freed up the aar. All this I and I have gotten the idle down from 4K to just under 2k. I can get it down to about 1100 but I have to remove the hose from the MPS? ( the Can on the right wall). The second I get the hose near or on the nipple the engine throttles up th 2 k. And runs smoother. At 1100 it sounds rich a lot of back firing. ( exhaust ignition). Any ideas gents?
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Brasil914
post Mar 7 2017, 08:10 AM
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QUOTE(Brasil914 @ Mar 7 2017, 09:02 AM) *

Hey all my name is John. I have been using 914 as a resource for a while but just registered (I have questions). So I have a 73 2.0 hand me down from dad. And I have idle issues. History: 86 dad snapped spark plug. Got what he could out of it and then tried to vacuum the head thru the spark hole. Was worried that not every thing was out so never started it again, and forgot to drain the tank. It sat in garage and storage until 2008 when he gave it to me. First thing I did was run a borescope in the cylinder , couldn't see jack. So dropped the motor pulled the head and the cylinder was clean as a whistle. Did some work over about three years sourcing parts and such. And got it to run in 2010. Then moved to SC. Got it here six months later and started on it some more. No I have had down time from work and have started tinkering again after 2 years. I have replaced all hoses,injectors and seals, yesterday I opened and freed up the aar. All this I and I have gotten the idle down from 4K to just under 2k. I can get it down to about 1100 but I have to remove the hose from the MPS? ( the Can on the right wall). The second I get the hose near or on the nipple the engine throttles up th 2 k. And runs smoother. At 1100 it sounds rich a lot of back firing. ( exhaust ignition). Any ideas gents?

Attached Image btw here is my beauty.
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BeatNavy
post Mar 7 2017, 08:22 AM
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The two most likely causes of a high idle in D-Jet, when everything else is adjusted and working, are vacuum leak and advanced timing. With a car that's been sitting for a long time, however, you REALLY need to go over everything -- all the sensors, all the wiring, valves adjusted, timing, fuel pressure, all potential seals/hoses, etc. etc. D-Jet works well and is not too hard to troubleshoot - except when it's been neglected for a long period of time. Then it can be a lot of "fun" to track down issues.

I know you said you replaced hoses and seals, which is good, but start trying to identify which ones maybe you didn't replace. Nothing is more frustrating (and fruitless) than chasing a symptom randomly or one with multiple root causes. So do your best to eliminate the variables:

1. Confirm timing.
2. Check to make sure there really are no vacuum leaks.
3. Connect that MPS again - can't really run without that, things go super-rich -- make sure it's functional
4. Verify ALL the sensors and various D-Jet components are serviceable and functioning correctly.

and most of all:

5. Read this website: http://members.rennlist.com/pbanders/djetparts.htm. That will help put a lot of this together so you can understand how things work. Good troubleshooting info there.

And (IMG:style_emoticons/default/welcome.png)
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Brasil914
post Mar 7 2017, 08:28 AM
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QUOTE(BeatNavy @ Mar 7 2017, 09:22 AM) *

The two most likely causes of a high idle in D-Jet, when everything else is adjusted and working, are vacuum leak and advanced timing. With a car that's been sitting for a long time, however, you REALLY need to go over everything -- all the sensors, all the wiring, valves adjusted, timing, fuel pressure, all potential seals/hoses, etc. etc. D-Jet works well and is not too hard to troubleshoot - except when it's been neglected for a long period of time. Then it can be a lot of "fun" to track down issues.

I know you said you replaced hoses and seals, which is good, but start trying to identify which ones maybe you didn't replace. Nothing is more frustrating (and fruitless) than chasing a symptom randomly or one with multiple root causes. So do your best to eliminate the variables:

1. Confirm timing.
2. Check to make sure there really are no vacuum leaks.
3. Connect that MPS again - can't really run without that, things go super-rich -- make sure it's functional
4. Verify ALL the sensors and various D-Jet components are serviceable and functioning correctly.

and most of all:

5. Read this website: http://members.rennlist.com/pbanders/djetparts.htm. That will help put a lot of this together so you can understand how things work. Good troubleshooting info there.

And (IMG:style_emoticons/default/welcome.png)

Yeah I'm really not wanting to drop the motor again but probably need to do it just to Make sure fine tooth comb it. Thanks beat navy. Hooah. Prior army myself.
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BeatNavy
post Mar 7 2017, 08:32 AM
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You don't need to drop the motor to do any of this! In fact it's best if you don't. You need to be able to fire it up and test things.

Go through that website from Mr. Anders and familiarize yourself with all the D-Jet components, how they work together, and how you KNOW they are working. Everything from the "big kahunas" (MPS and CHT) that will screw everything up to the more minor stuff like AAR and Ambient Air Temp sensor.

Give us feedback and we'll help.

Very pretty car, too!
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JawjaPorsche
post Mar 7 2017, 11:51 AM
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Did you replace the manifold gaskets? Air intake gaskets?
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DRPHIL914
post Mar 7 2017, 01:15 PM
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QUOTE(JawjaPorsche @ Mar 7 2017, 12:51 PM) *

Did you replace the manifold gaskets? Air intake gaskets?


Welcome fellow SC resident!- just down the road in Bluffton- (IMG:style_emoticons/default/welcome.png)

When I first got my car 7 years ago - I had a high idle - it was 3 fold
1. vac leaks- will always cause high idle-
- common leaking points is open AAR, intake manifold leaks and throttle body leaks, and vac hoses connected to plenum and t.b.
2. lean running due to MPS was going bad or not calibrated correctly when rebuilt
3. timing set correctly- your advance is off and valves should be adjusted.

- a hunting idle is also sign of very lean running car- checking plugs can clue you in to how rich or lean your car is running.
- when an MPS fails it usually goes rich flooding the car out so it would not start. but I have had one go bad the other way so lean that when unplugged it actually ran, otherwise would not start it was so lean - that MPS I rebuilt and recently retuned it. and now runs great!!

nice color too btw! take a drive once its on the road and come down to 3rd Saturday cars and coffee at the Bluffton campus of USC-B near Sinn City!- sorry I mean Sun City

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DRPHIL914
post Mar 7 2017, 01:45 PM
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reading back thru it seems if you have evaluated all the hoses and seals that next thing is timing, advance etc- check the advance plate motion in the distributor- it could be sticking- if you pull the vac hose off the distributor it should speed up, put it back on and will slow down a few hundred rpm. if so its probably working fine, if not that's the next thing to check along with overall timing. you should be closer to 900 rpm- although mine is about 100-1100 right now when warm and my next project is setting valves and then rechecking my timing- but because ive been tuning the newly rebuilt MPS that may need a tweek or 2 yet as well. -

don't pull that vac hose off the MPS its going way rich and will flood out fouling up your plugs. - 2 things you cant do and have the car run 1. CHT cannot be disconnected(cylinder head temp sensor). 2. MPS connected.
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Dave_Darling
post Mar 7 2017, 03:41 PM
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Make sure that you don't have any hoses that go directly from the air cleaner to the manifold. There should always be some kind of component in between, like the AAR or the decel valve.

--DD
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cgnj
post Mar 7 2017, 03:57 PM
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Unmetered air. Check for leaks at the phenolic gaskets between the runners and heads.4K idle = a lot of air.
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Rand
post Mar 7 2017, 04:08 PM
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4k idle can only be a huge open hole below the butterfly (throttle body). Only so many places it can be. Timing, valve adjust, etc are important, but no way causing that high of an idle. It's a massive air leak, bigger than leaky injector seals, phenolic blocks, etc. Something is open.
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BeatNavy
post Mar 7 2017, 05:03 PM
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I think it WAS 4K before he started hunting down leaks and replacing hoses/seals. It's now about 2K, which still implies timing and/or additional leaks.
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Brasil914
post Mar 7 2017, 06:40 PM
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QUOTE(Rand @ Mar 7 2017, 05:08 PM) *

4k idle can only be a huge open hole below the butterfly (throttle body). Only so many places it can be. Timing, valve adjust, etc are important, but no way causing that high of an idle. It's a massive air leak, bigger than leaky injector seals, phenolic blocks, etc. Something is open.

It was a missing injector seal dut that was fixed. Before the post. Thank you all for the help. DD your every where haha. And when I do get it fully on the road I'll come done to bluffton. So as an update I was working on timing today. New points set the gap but noticed the primary copper wire was broke free of the plate so I sandwiched it between plate and points. Probably needs replaced. Put a timing light on it and was still off a little. Is the green or black hose the advance? (Newbie question I know ). I did pull a vacuum on the Mps and it held 18-20 psi for 10 min. Aar has been opened and freed. Throttle body and cold start have been resealed wit liquid gasket. Because I could find any. Just to let y'all know this is a 73 wit 26k original miles on it so never rebuilt never pulled apart (till now). Other than the hisses and fuel pump , oil and filter, and front clip. Everything is original. Shoot the four rubber rings on it are 83' rounded edge radials.
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Rand
post Mar 7 2017, 06:42 PM
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Do you know Gunn1? OU812? Your style is so similar. (IMG:style_emoticons/default/idea.gif)

83 feet of tire?

You can't just sandwich that wire between the plates. Good spark depends on that braided wire having a quality soldered connection.
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Brasil914
post Mar 7 2017, 06:51 PM
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I have to keep hunting for a leak I capped the throttle body and it kept running. So I think I'm gonna cap it and try a fog or liquid spray to see if I can't find it. All hoses on vacuum side are a kit from AA so routed per their cheat sheet that I still have . Do you guys recommend clamps on all?
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Brasil914
post Mar 7 2017, 06:56 PM
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QUOTE(Rand @ Mar 7 2017, 07:42 PM) *

Do you know Gunn1? OU812? Your style is so similar. (IMG:style_emoticons/default/idea.gif)

83 feet of tire?

You can't just sandwich that wire between the plates. Good spark depends on that braided wire having a quality connection.

Hahah no I don't. It was a Johnny on the spot fix. There was no way I was going to get a distributor today, so I made due. It was foreign pretty well. Plus got a wedding in less than a month. So new distributor will only be after that. 1983 rubber ! Dad worked for BFG.
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Brasil914
post Mar 7 2017, 06:58 PM
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QUOTE(Rand @ Mar 7 2017, 07:42 PM) *

Do you know Gunn1? OU812? Your style is so similar. (IMG:style_emoticons/default/idea.gif)

83 feet of tire?

You can't just sandwich that wire between the plates. Good spark depends on that braided wire having a quality soldered connection.

Of course I cold re solder it I suppose. I am a electrical technician. (IMG:style_emoticons/default/av-943.gif)
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Rand
post Mar 7 2017, 07:43 PM
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So your car is running ok (aside from the fast idle) with that braided wire just sandwiched between the distributor advance plates?
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Brasil914
post Mar 7 2017, 10:22 PM
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QUOTE(Rand @ Mar 7 2017, 08:43 PM) *

So your car is running ok (aside from the fast idle) with that braided wire just sandwiched between the distributor advance plates?

When I saw it loose my heart sank. But I tried a temp fix of sandwiching it between the points bracket and the top advance plate. And so far it's working. But I'm gonna solder it tomorrow.
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rhodyguy
post Mar 8 2017, 08:19 AM
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Did you only replace the ONE injector seal or all EIGHT of them?
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