New book title: Return of the Hanging Idle
09-30-2018 | 12:55 PM
#1
Thread Starter
Three Wheelin'
Joined: Jan 2017
Posts: 1,801
Likes: 44
New book title: Return of the Hanging Idle
I have completed my intake refresh with all needed goodies!
If Roger, Sean, Stan, Speedtoys, and especially worf928 wanna give me an at-a-boy,
or some sugar, I will take it! lol thanks for everyone's hope and guidance.
Most everything was in great shape, and that "oh my God" moment after completion, didn't happen: no regrets, things needed to be done, I just thought I would have experienced a more pronounced difference.things were just not as bad as others have experience. thanks to previous owners!
my biggest issues of leaking intake, hanging idle and too rich a mixture have been solved.
injectors were cleaned and balanced, intake smoke tested and vacuum leaks corrected. a new MAF,
O2, CPS, knock sensors, hall sensor, flappy diaphragm, and lots more, all contributed to the results.
(the irritating hanging idle was actually mechanical due, to a binding Bowden cable accel wheel)
so...… after 300 or so miles, I "occasionally" have a "slight" handing idle. hard to describe, but it rarely, happens.
perhaps 8 or 9 times out of ten, after any drive time, coming to a stop light, the car will drop down to the proper
idle, (775) immediately. but "sometimes," it will hang up, just a little bit (900), for about 5 to 10 seconds. more often, this slightly hanging idle occurs more often after shutting down, and restarting.
I can confirm that the cable does not seem to be the issue. does this sound like anything obvious? the very last thing
I have not replaced, is my cracked dipstick...…????? could that create a vacuum leak? can an air leak be intermittent?FWIW: I am running WR5DC (colder) WR7DC. and the plug look very clean or possibly lean; maybe 300 miles is not enough to read the plugs?
If Roger, Sean, Stan, Speedtoys, and especially worf928 wanna give me an at-a-boy,
or some sugar, I will take it! lol thanks for everyone's hope and guidance.
Most everything was in great shape, and that "oh my God" moment after completion, didn't happen: no regrets, things needed to be done, I just thought I would have experienced a more pronounced difference.things were just not as bad as others have experience. thanks to previous owners!
my biggest issues of leaking intake, hanging idle and too rich a mixture have been solved.
injectors were cleaned and balanced, intake smoke tested and vacuum leaks corrected. a new MAF,
O2, CPS, knock sensors, hall sensor, flappy diaphragm, and lots more, all contributed to the results.
(the irritating hanging idle was actually mechanical due, to a binding Bowden cable accel wheel)
so...… after 300 or so miles, I "occasionally" have a "slight" handing idle. hard to describe, but it rarely, happens.
perhaps 8 or 9 times out of ten, after any drive time, coming to a stop light, the car will drop down to the proper
idle, (775) immediately. but "sometimes," it will hang up, just a little bit (900), for about 5 to 10 seconds. more often, this slightly hanging idle occurs more often after shutting down, and restarting.
I can confirm that the cable does not seem to be the issue. does this sound like anything obvious? the very last thing
I have not replaced, is my cracked dipstick...…????? could that create a vacuum leak? can an air leak be intermittent?FWIW: I am running WR5DC (colder) WR7DC. and the plug look very clean or possibly lean; maybe 300 miles is not enough to read the plugs?
09-30-2018 | 02:47 PM
#3
Thread Starter
Three Wheelin'
Joined: Jan 2017
Posts: 1,801
Likes: 44
Did you remove the throttle plate at all? It can only be installed one way. If flipped around, it can stick.
09-30-2018 | 09:00 PM
#4
Team Owner
Joined: May 2004
Posts: 28,637
Likes: 2,661
From: Philly PA
glad you did all this work
FWIW the throttle plate bearings are probably leaking and the new TPS will begin to fill with oil pretty fast.
If the bearings are original then the rubber O ring seals are pretty much done.
Roger sells new double sided O ring bearings .
the new bearings work much better to reduce the oil migration, and reduce vacuum leaks
FWIW the throttle plate bearings are probably leaking and the new TPS will begin to fill with oil pretty fast.
If the bearings are original then the rubber O ring seals are pretty much done.
Roger sells new double sided O ring bearings .
the new bearings work much better to reduce the oil migration, and reduce vacuum leaks
10-01-2018 | 07:20 AM
#5
Rennlist Member
Joined: Sep 2010
Posts: 13,582
Likes: 1,034
From: Boulder Creek, CA
Good work.
Ya...I dont think ive seen a reason NOT to do the throttle shaft bearings, since that's the deepest thing you never need to replace, and fairly trivial. I got lucky and a HF bearing puller tool worked on these.
I cant say this -is- the issue, just make sure there is a click when you hear the idle switch when you check the cable adjustment, and theres JUST enough free cable to get a click, and juuuuuust a hair more; Enough that there is no tension on the cable but not so much is it entirely slack.
Also, did you replace the throttle quadrant bearings??
92811067702 (#21, $45-48)
You can often find that they have worn and started to dig into the quadrant shafts, and this can add some stick to the throttle. It was so much on my 88, that light cruise at 35mph, and lift...the throttle would stay there.
I think most people have a bad bearing or two in there, and a lip worn into the shaft as well waiting to cause 'old car personality' issues.
https://rennlist.com/forums/928-foru...nt-levers.html
You dont need new arms, unless you want pretty ones...the bearings press out and in fairly well. A vise and some sockets can get er done.
Ya...I dont think ive seen a reason NOT to do the throttle shaft bearings, since that's the deepest thing you never need to replace, and fairly trivial. I got lucky and a HF bearing puller tool worked on these.
I cant say this -is- the issue, just make sure there is a click when you hear the idle switch when you check the cable adjustment, and theres JUST enough free cable to get a click, and juuuuuust a hair more; Enough that there is no tension on the cable but not so much is it entirely slack.
Also, did you replace the throttle quadrant bearings??
92811067702 (#21, $45-48)
You can often find that they have worn and started to dig into the quadrant shafts, and this can add some stick to the throttle. It was so much on my 88, that light cruise at 35mph, and lift...the throttle would stay there.
I think most people have a bad bearing or two in there, and a lip worn into the shaft as well waiting to cause 'old car personality' issues.
https://rennlist.com/forums/928-foru...nt-levers.html
You dont need new arms, unless you want pretty ones...the bearings press out and in fairly well. A vise and some sockets can get er done.
10-02-2018 | 10:39 AM
#7
Thread Starter
Three Wheelin'
Joined: Jan 2017
Posts: 1,801
Likes: 44
Ya...I dont think ive seen a reason NOT to do the throttle shaft bearings, since that's the deepest thing you never need to replace, and fairly trivial. I got lucky and a HF bearing puller tool worked on these.
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10-02-2018 | 09:51 PM
#8
Team Owner
Joined: May 2004
Posts: 28,637
Likes: 2,661
From: Philly PA
best thing to use to remove the bearings is a moly bolt
pry the inner race out of the bearing with the rollers,
then fit the moly bolt tighten the nut to spread the fingers make sure the fingers are filed flat ,
some moly bolts have curved tips this wont work.
Take a piece of metal rod about 12 inches long tap the moly bolt and the bearing race will come free
NOTE add some heat to the inner area of the part to assist in expanding the metal
pry the inner race out of the bearing with the rollers,
then fit the moly bolt tighten the nut to spread the fingers make sure the fingers are filed flat ,
some moly bolts have curved tips this wont work.
Take a piece of metal rod about 12 inches long tap the moly bolt and the bearing race will come free
NOTE add some heat to the inner area of the part to assist in expanding the metal
10-03-2018 | 02:57 AM
#9
Rennlist Member
Joined: Sep 2010
Posts: 13,582
Likes: 1,034
From: Boulder Creek, CA
10-03-2018 | 10:01 AM
#10
Thread Starter
Three Wheelin'
Joined: Jan 2017
Posts: 1,801
Likes: 44
FWIW the throttle plate bearings are probably leaking and the new TPS will begin to fill with oil pretty fast.
If the bearings are original then the rubber O ring seals are pretty much done.
Roger sells new double sided O ring bearings .
the new bearings work much better to reduce the oil migration, and reduce vacuum leaks
If the bearings are original then the rubber O ring seals are pretty much done.
Roger sells new double sided O ring bearings .
the new bearings work much better to reduce the oil migration, and reduce vacuum leaks
at start up, or after driving a bit? if I start the car from cold, and let it sit, the idle is rock steady at 775, no matter how long I let it sit?