1982 SC Wants to Idle at 1400!!

[Vincent Hill]

With the Idle Air Screw all of the way "IN" Timing set correctly and A/F set so the car starts with no Stalling, it wants to Idle between 1400 to 1600.

I made sure the Throttle stop screw is down and the Linkage has free play.

The "ONLY" Way I can lower the Idle is to Retard the timing and richen the fuel to the point that the car starts rough when starting it up, it eats more fuel and I have less Power due the the retarded timing!

The Only thing Non Stock is the Permatune high Out-Put Ignition box and I did not open the Plug Gaps to .065 as suggested. Could that cause the extra 500 RPMS??

This is a New Problem for me! It is usually a problem trying to get an Idle!

[equality72521]

Sounds like a major vacuum leak to me. Double check everything.

[crustychief]

I second the vacuum leak thingy that Mark said. Does the idle change when you remove the oil cap?

[Vincent Hill]

It almost Stalls out when I remove the Oil Cap even with the reducer!

I guess I will Spray Some Carb Cleaner everyhwere. I found some Loose screws in rhe Air Box near the Pop Valve!

[equality72521]

Look for cracked/loose hoses.

[boyt911sc]

Originally Posted by Vincent Hill

With the Idle Air Screw all of the way "IN" Timing set correctly and A/F set so the car starts with no Stalling, it wants to Idle between 1400 to 1600.

I made sure the Throttle stop screw is down and the Linkage has free play.

The "ONLY" Way I can lower the Idle is to Retard the timing and richen the fuel to the point that the car starts rough when starting it up, it eats more fuel and I have less Power due the the retarded timing!

The Only thing Non Stock is the Permatune high Out-Put Ignition box and I did not open the Plug Gaps to .065 as suggested. Could that cause the extra 500 RPMS??

This is a New Problem for me! It is usually a problem trying to get an Idle!

Vincent,

While most of the suggestions that you received refer to vacuum leak, using a good method is the key. While a lot of guys use propane or carb cleaner to locate air leaks in a running engine, I prefer using low pressurize air (5 - 10 psi). Simply because you could locate conveniently sources of air leak/s even in a non-running engine. Air leak coming from the air box is not easy to find specially if the engine is installed in the car. Whichever method you choose, keep us posted of your progress.

Tony

[stlrj]

I would suspect a cracked air box.

[Vincent Hill]

The Carb Cleaner is what I use when I remember to "Think" about Vacuum Leaks!

I first sprayed the Injectors and 4 out of 6 raised the Idle! I sprayed the Base of the Inlet Runners and no change. I sprayed the Rubber Tubes that mount the AirBox to the Runners, 1 place left side and do not know which one or ones but when I sprayed Under the AirBox Right side the Idle Raised. I sprayed in Back of the AirBox and no Changes. Around the Oil Cap and no changes. I also noticed the Charcoal Cannister had no tube facing the Oil Cap?

Looks like I need to get a new Set of Injector "0" Rings and New Hoses to the AirBox, PLUS Check the Airbox! WORK Work work!! I am too Old for this! I just Finished getting the 1976 apart and out of the Yard, Cleaned up my GT40 Kit Car and Moved the 2003 Mini Cooper S in the Yard to replace the entire Front end (Steering Rack, Both Axles, Control Arm Bushings, Camber Plates (Top of the SHock) Radiator Fan, Cat I made to Fit the Headers and who knows what else??

[Flat6pac]

It sounds like you have the vacuum lines to the distributor reversed and doing the wrong thing. The idle should vacuum retard by having the butterfly closed and the vacuum go from 5 degrees before TDC to 7 to 10 degrees after TDC.
If youre set to advance your spark with the idle hose you will advance and idle higher.
Bruce

[tcar]

Originally Posted by stlrj

I would suspect a cracked air box.

+1, especially with the loose screws near the POV.

[Daviboy]

+1 on cracked airbox especially if there are loose screws!

[Vincent Hill]

When I get New "0" rings for the injectors and Rubber Hoses I will remove the AirBox and see Everything. Right Now I think I have Vacuum Leaks at the Injector 0 Rings and loose Hose Clamps. For Grins I will verse the Vacuum Lines But do not think that is the Problem. Tonight I will spray WD 40 and then Belray Chain Lube at each Injector to see if I can get a Temp Seal!

[flat6pilot]

+1 on the cracked airbox. Exact same thing happened to me.


Make sure you check that your AAR is closing before changing the air box though. It should close by applying 24VDC to it. You can hook it directly to the battery if you can get it out and look at it on the bench. Should take ~approx 5mins or so to close.

[Vincent Hill]

OK, When my wife came in, I had her leave the car running. I sprayed each Injector 1 at a time first with a shot of WD-40, Immediately followed by BelRay Motorcycle chain Lube (It is a light liquid that turns into a thick sticky White Grease. I figured the WD-40 would lube the way for it to coat everything. When I got finished, Advanced the timing to where it should be and leaned out the A/F a little and then turned off the engine. I let everything set up for a few hours and restarted the car and drove to the gas Station. When Colder it Idled at 800 and when Hot 950. This is after an 6 to 8 mile drive.

Monday I will get New Inserts and the "0" rings for the Inserts and Injector "0" Rings. Once I replace these things, It should give me a little breathing space until I have time to completely remove the Airbox and Runners and replace the Rubber there and take apart the Airbox and Reseal it and Clean up the threads then put a serious Plastic Glue into the threads so that the Screws will have NEW Plastic to bite into.

Equality. Crusty Chief & BoyToy Thank you, I have never thought about using Propane over Carb Cleaner? Since Propane is a Heavy Gas I am also a little afraid of it also! Nothing like this place, so this MUST be the Place

[Vincent Hill]

Up-Date! Dead Cold this morning I started the car. For the First time in my memory the car did not go to a High Rev ever! It started and was at about 1200 and then down to 800and I had to hold the throttle if I wanted it to run steady. After a few minutes I drove it up the street and the Power was OK. By the time my wife got to work the Idle would be 11 to 1200 and then it was steady Idle at about 1000.

I ordered New Injector 0 Rings, New Inserts and 0 Rings and new Rubber Hoses that connect the Intake Runners to the Airbox. Hopefully this weekend I will change all of the 0 rings and inserts which I hope will make it run well enough to allow me a few weeks to catch up on a few other things.

My thought is, 100 degree heat with (Most Likely) original parts (125,000 Miles) took the seal out of the 0 rings and hardened them.

[Vincent Hill]

Up Date! Yesterday I pulled out the Injectors and Several "0" Rings "Broke"! Then when I removed the Inserts, There were "NO" 0 rings in tact! I was able to remove the Inserts by using a Motorcycle Spring installation Tool made by Hindle Exhaust



I "KNOW" I have more work to do but, just this helped 95%. I now have the Timing back to where it should be and the Fuel is very close!

I have new Rubber for the Airbox to Runners and will check the Airbox but at least now I have TIME! Anyone with an SC or older that use this kind of Fuel system should take a SERIOUS look at these parts!

[Vincent Hill]

How about the answer to my problems! "All of the Above".

I took everything apart and first realized that I had not seated the Injectors Sleeves and when I sprayed them some raised the RPM. ALso one base gasket for the Inlet runner was leaking. and of course it was either the Airbox or the rubber connectors (I replaced all of them with new ones) that were leaking.

I spent a lot of time trying to seal up the Airbox and fix the loose screws. I was putting everything back together and was having serious fun getting in the last runner on the right side and heard a Pop. I cracked one of my repairs and when I started the car up, the area under the Airbix leaked like a Seive.

I bit the Bullet and got a friend of mine at the Porsche dealer get me a new AirBox which I am now installing a new Pop Valve. The #1 thing I see with the New AirBox is that Porsche did not try to hide the fact that they seriously need to be glued between the Upper and Lower.

I hope to finish the Mini Cooper this weekend (Steering Rack, Control Arm Bushings, Inner Ball joints, New Camber plates on top of the Struts, Left & Right Drive Shafts, Braided cable Brake lines, New Radiator Fan and lower adjustable Links in the rear slong with a new Catalytic Converter I just made. Neat cars but nothing is made to last any length of time over 75 to 100K Miles. I have already replaced the Head because the short valve guides wore out at 100K. I would not buy another one but my wife likes it so you do what you must do!