adjusting idle speed on FI ... almost bottomed out.
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- IAC Addict!
- Location: Metro Detroit
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adjusting idle speed on FI ... almost bottomed out.
I am only about 1/2 a turn from completely closing (tightening) the big idle adjustment screw to get my bus in the 900 rpm range. Loosing does a very good job of speeding the idle up (meaning the passage isn't blocked/the adjustment works).
What does this mean? What else may be out of adjustment to cause this to be so radically off?
Cheers,
Mike
What does this mean? What else may be out of adjustment to cause this to be so radically off?
Cheers,
Mike
1976 VW Bus aka tripod
FI ...not leaky, and not so noisy...and she runs awesome!
FI ...not leaky, and not so noisy...and she runs awesome!
hambone wrote: There are those out there with no other aim but to bunch panties. It's like arguing with a pretzel.
- BellePlaine
- IAC Addict!
- Location: Minnesota
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Re: adjusting idle speed on FI ... almost bottomed out.
Too much fuel pressure?TrollFromDownBelow wrote:What else may be out of adjustment to cause this to be so radically off?
Cheers,
Mike
1975 Riviera we call "Spider-Man"
- Westy78
- IAC Addict!
- Location: Stumptown OR
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Re: adjusting idle speed on FI ... almost bottomed out.
Faulty/lazy decel valve. Squeeze the hose from the S boot to the valve and see if the idle drops.
Sticky throttle body not returning to fully closed position. This was a problem on mine the other day.
Throttle cable adjusted to tight.
Just to name a few spots to check.
Sticky throttle body not returning to fully closed position. This was a problem on mine the other day.
Throttle cable adjusted to tight.
Just to name a few spots to check.
Chorizo, it's what's for breakfast.
- Amskeptic
- IAC "Help Desk"
- Status: Offline
Re: adjusting idle speed on FI ... almost bottomed out.
Add to the list, the very typical auxiliary air regulator not closing fully, and add VACUUM LEAK that has been compensated by a fuel mixture adjustment that now allows the engine run fine, but too much air to let the idle drop down.Westy78 wrote:Faulty/lazy decel valve. Squeeze the hose from the S boot to the valve and see if the idle drops.
Sticky throttle body not returning to fully closed position. This was a problem on mine the other day.
Throttle cable adjusted to tight.
Just to name a few spots to check.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles
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- Getting Hooked!
- Location: Gulf Breeze, Florida
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Re: adjusting idle speed on FI ... almost bottomed out.
Not to high Jack but I just fixed a tear in my EEC diaphram per Colin. Because my fuel ratio was running lean (1979 CA stock) I needed to get my head temps down. I got the glob of silicone out of the set screw on the wiper adjustment and moved it one tooth CCW. It is now running rich (13 MPG) with black sooty plugs. The idle pre set was 1 1/2 turns before bottoming out. I unscrewed it to 4 1/2 out.
If I set the tooth back to original setting does it stand to reason the head temps will go up some but the af ratio will also go up and go to a more factory default rich?
Thank
Jack
If I set the tooth back to original setting does it stand to reason the head temps will go up some but the af ratio will also go up and go to a more factory default rich?
Thank
Jack
- airkooledchris
- IAC Addict!
- Location: Eureka, California
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Re: adjusting idle speed on FI ... almost bottomed out.
jackstar wrote:Not to high Jack but I just fixed a tear in my EEC diaphram per Colin. Because my fuel ratio was running lean (1979 CA stock) I needed to get my head temps down. I got the glob of silicone out of the set screw on the wiper adjustment and moved it one tooth CCW. It is now running rich (13 MPG) with black sooty plugs. The idle pre set was 1 1/2 turns before bottoming out. I unscrewed it to 4 1/2 out.
If I set the tooth back to original setting does it stand to reason the head temps will go up some but the af ratio will also go up and go to a more factory default rich?
Thank
Jack
your talking about the idle mixture adjustment on the AFM though, and not the idle speed adjustment on the throttle body correct?
it should be noted here that you do have the O2 sensor disconnected at this point, otherwise none of those adjustment changes would have done anything.
I wouldn't assume that your temps will go back up. You can go too far to the rich side of things where leaning it out some could actually maintain your temps and get you better fuel economy.
question - when your at a stop light - if you pump the brakes, does the idle speed increase?
1979 California Transporter
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- Getting Hooked!
- Location: Gulf Breeze, Florida
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Re: adjusting idle speed on FI ... almost bottomed out.
Funny you should mention idle speed. Not long after making my adjustments I noticed my engine would have a high idle anytime I came up to a light, stop sign or to park. It would stay high even after tapping the gas pedal and would only return to a normal idle if I put in gear and let clutch out a bit to put under load. After that no problem until the next stop.
I don't know the significance of it but I am sure someone does. I think I am going check the mix with Randy in Maine's LM-1. And then put back to the original tooth location and see where that puts me. Yes Chris the 02 is very disconnected. When you get around to that toggle idea let me know I am interested.
Jack
I don't know the significance of it but I am sure someone does. I think I am going check the mix with Randy in Maine's LM-1. And then put back to the original tooth location and see where that puts me. Yes Chris the 02 is very disconnected. When you get around to that toggle idea let me know I am interested.
Jack
- dtrumbo
- IAC Addict!
- Location: Mill Creek, WA
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Re: adjusting idle speed on FI ... almost bottomed out.
Another possibility is your distributor is sticky and therefore not un-advancing (that's a word?) as the engine slows down. I had the exact same thing in my Beetle. I'd have to slip the clutch at a stop light to get it to idle properly. Getting the distributor overhauled fixed the problem immediately.
- Dick
1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.
... as it turns out, it was the coil!
1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.
... as it turns out, it was the coil!
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- Getting Hooked!
- Location: Gulf Breeze, Florida
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Re: adjusting idle speed on FI ... almost bottomed out.
I will look at both situations. I need to do a search on testing the decel valve and if faulty I will start there. If that is not a solver, then onto the dizzy. Thanks guys for the insight.
Jack
Jack
- Gypsie
- rusty aircooled mekanich
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Re: adjusting idle speed on FI ... almost bottomed out.
This is the easiest way to see if the Decel diaphram is blown. Nuthin but a squeeze to block the flow. If the idle drops when you squeeze it it's a great indicator.Westy78 wrote:Faulty/lazy decel valve. Squeeze the hose from the S boot to the valve and see if the idle drops.
If it does drop, disconnect and block the hose and try a test drive.
All the other items can follow if this aint it.
So it all started when I wanted to get better gas mileage....
- Amskeptic
- IAC "Help Desk"
- Status: Offline
Re: adjusting idle speed on FI ... almost bottomed out.
Return, Dick, the word is "return" and you are spot-on.dtrumbo wrote:Another possibility is your distributor is sticky and therefore not un-advancing (that's a word?) as the engine slows down. I had the exact same thing in my Beetle. I'd have to slip the clutch at a stop light to get it to idle properly. Getting the distributor overhauled fixed the problem immediately.
Colin
(set warm idle for 950-999 rpm to not trigger the centrifugal advance > note: if you lubricate the advance weights and all, you will make the problem worse of course, so bend the spring post of the weight that has no slop to make sure it is exerting a slight pull)
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles
- airkooledchris
- IAC Addict!
- Location: Eureka, California
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Re: adjusting idle speed on FI ... almost bottomed out.
did you get it fixed?jackstar wrote:I will look at both situations. I need to do a search on testing the decel valve and if faulty I will start there. If that is not a solver, then onto the dizzy. Thanks guys for the insight.
Jack
if so, which was it?
1979 California Transporter
- airkooledchris
- IAC Addict!
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Re: adjusting idle speed on FI ... almost bottomed out.
Amskeptic wrote:(set warm idle for 950-999 rpm to not trigger the centrifugal advance > note: if you lubricate the advance weights and all, you will make the problem worse of course, so bend the spring post of the weight that has no slop to make sure it is exerting a slight pull)
does the above look/sound right? I still have the picture you drew for me, but looking through that little window is trickier than id expected.
one of the springs looks slightly longer than the other one, if that means anything.
I checked out my own decel but pinching didn't cause the idle to slow down and disconnecting it from the S boot and revving hard will create suction on that hose, so I think it's OK.
1979 California Transporter
- SlowLane
- IAC Addict!
- Location: Livermore, CA
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Re: adjusting idle speed on FI ... almost bottomed out.
It very much means something.Chris wrote:one of the springs looks slightly longer than the other one, if that means anything.
The two springs in the distributor are constructed quite differently. One has a circular loop in both ends, the other has a circular loop on one end and an elongated loop on the other. The one with both circular loops should be under tension under all conditions. That's the one for which you want to adjust the post until there is no slop.
The elongated loop on the other spring is there to prevent it from coming into play until a certain amount of advance is attained, then once it is in play, it will slow the rate of advance by providing more resistance to the weights.
That's why you see advance specifications like this example:
The 8-13 degrees @ 1600 RPM is entirely due to the action of the two-circular-loop spring. At that RPM, the elongated-loop-spring comes into play because the weights have moved far enough that the end of the elongated loop has been reached. From 1600 RPM to 3400 RPM, both springs are resisting the weights movement, so you get less advance per RPM increase. At 3400 RPM the weights should hit their hard stops and no more advance should be seen as engine speed increases over 3400 RPM.Old Volks wrote:Advance/Retard Range: Vacuum: 8.5-11deg Adv @ 7.9 In. Hg; Centrifugal: 8-13deg @ 1600 rpm, 20.5-24.5 @ 3400 rpm
'81 Canadian Westfalia (2.0L, manual), now Californiated
"They say a little knowledge is a dangerous thing, but it is not one half so bad as a lot of ignorance."
- Terry Pratchett
"They say a little knowledge is a dangerous thing, but it is not one half so bad as a lot of ignorance."
- Terry Pratchett
- airkooledchris
- IAC Addict!
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Re: adjusting idle speed on FI ... almost bottomed out.
I am going to try this sometime this week.
My issue is def the distributor and I was able to replicate it last night in my driveway.
Went for a cruise around town to get everything warmed up, then backed it into the driveway to check the timing. Timing was holding steady at 5* ATDC but when I went to rev it up to see where the max advance was it wouldn't come back down - then holding steady at 1* ATDC and blipping the throttle wasn't bringing it back down to 5* again - it was just stuck here. Shutting the engine off and letting it cool for a bit will set it back of course.
This has been sending me on a wild good chase of trying to get it to idle properly because it'll be running at 1200/1300 RPM and if I bring that down to 950 - it'll end up idling at 700 RPM the next time I start it up.
I can't say that im too excited to be trying to bend that metal post inside my distributor but ill give it a shot - but will keep the Philbin group in mind in case I want to have it professionally overhauled instead.
There is a federal coil and distributor in my tool box that I know works - but I read a thread over at TS earlier this year where someone had a lot of issues trying to just swap in the federal setup (for starters it's just a SVDA where my current is a DVDA unit)
My issue is def the distributor and I was able to replicate it last night in my driveway.
Went for a cruise around town to get everything warmed up, then backed it into the driveway to check the timing. Timing was holding steady at 5* ATDC but when I went to rev it up to see where the max advance was it wouldn't come back down - then holding steady at 1* ATDC and blipping the throttle wasn't bringing it back down to 5* again - it was just stuck here. Shutting the engine off and letting it cool for a bit will set it back of course.
This has been sending me on a wild good chase of trying to get it to idle properly because it'll be running at 1200/1300 RPM and if I bring that down to 950 - it'll end up idling at 700 RPM the next time I start it up.
I can't say that im too excited to be trying to bend that metal post inside my distributor but ill give it a shot - but will keep the Philbin group in mind in case I want to have it professionally overhauled instead.
There is a federal coil and distributor in my tool box that I know works - but I read a thread over at TS earlier this year where someone had a lot of issues trying to just swap in the federal setup (for starters it's just a SVDA where my current is a DVDA unit)
1979 California Transporter