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Just keep plugging.

Last week I did the spray Sea Foam treatment through one of the vacuum lines off the throttle body. Not sure how much that helped but I like to get that done before the first oil change. I did the oil change yesterday and ran the car up and down the drive (about 900' long) and played with the throttle quite a bit. The symptom is the car idles really well at 850 rpm. When you place the trans in drive, it sometimes stumbles and quits. After warming up real good, it usually doesn't stumble when you put it in drive but almost always does if you give more than just a tiny bit of throttle. Same is true when in park. However, if you very slowly apply throttle and get it up around 2000 rpm, it runs very well and responds to throttle quickly. It also will seem to hunt timing around 1200-1500 rpm. It was exhibiting those symptoms last week so I went ahead and ordered new plugs and a replacement TPS. I installed those today which meant pulling the intakes off cylinders 1-4 and the main T pipe. Then I just unbolted the throttle body and lifted it enough to change out the TPS. Just taking 1/2 the intake apart. Of course while I was putting the injector rail back on I broke one of the little vacuum tits off the thermo valve. Anyway, the new plugs and TPS didn't change anything so if anyone has some ideas... I'm open to suggestions.
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Current projects - '85 928S, '87 924S, '82 931, '14 Cayman
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Old 10-21-2017, 06:40 PM
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Get other input but wondering if the MAF is iffy.
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1974 911 w/ 3.2 (ugly but kinda fast)
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Old 10-21-2017, 09:22 PM
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Quote:
Originally Posted by tdskip View Post
Get other input but wondering if the MAF is iffy.
Yeah, that was kinda what I was thinking. Nothing inexpensive about those

Also... I noticed an open port on the air filter box on the passenger side. Not the large one that come off the air pump but above and on the side. If that is a large vacuum port to ??? then that would explain the poor running condition. No noticeable hoses are loose however.
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Tennessee Region SCCA & PCA
Current projects - '85 928S, '87 924S, '82 931, '14 Cayman
Past projects - '72 Opel GT, '75 280Z, '90 300ZX, '87 944S, '87 944 Turbo, '88 924S (x2), '02 Boxster, '07 Cayman S, '73 914
Old 10-22-2017, 04:26 AM
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Trace that, believe it is connected to the engine.

Do that before fussing with the MAF
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1974 911 w/ 3.2 (ugly but kinda fast)
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1984 928s (yeah, I really did buy a non running 928)
Old 10-22-2017, 06:10 AM
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Another success tonight. I got another shipment of parts from 928R Us including a rebuilt AFM. I replaced that, all the intake hoses, the 4-way vacuum splitter under the manifold and the thermo switch. Got everything back together and fired it up. Great start, perfect idle and the throttle responds just like it should. Took the car out on the streets and it's runner really well. Jump the throttle to the kick-down and this thing pulls like a horse! I'm very pleased tonight. Now I can go to work on some of the more cosmetic details like instrument panel lights, air conditioning and the interior rear view mirror that came loose recently.
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Current projects - '85 928S, '87 924S, '82 931, '14 Cayman
Past projects - '72 Opel GT, '75 280Z, '90 300ZX, '87 944S, '87 944 Turbo, '88 924S (x2), '02 Boxster, '07 Cayman S, '73 914
Old 11-03-2017, 07:50 PM
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Great!
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1974 911 w/ 3.2 (ugly but kinda fast)
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Old 11-04-2017, 05:12 AM
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1981 928 Euro "Babied and Pampered"
Old 11-04-2017, 10:05 PM
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Baby has new shoes!

I took delivery on some new tires. Went with Riken 225x50x16 on the BBS wheels that came with this car. Tire Rack had a special on those and I couldn't beat the price. It does look much better with the correct OD wheel & tire. With the OE tire inflation, the car rides really well. Much stiffer than I thought it would. Next I'm digging into the instrument panel for bulb and odometer gear replacement.



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Tennessee Region SCCA & PCA
Current projects - '85 928S, '87 924S, '82 931, '14 Cayman
Past projects - '72 Opel GT, '75 280Z, '90 300ZX, '87 944S, '87 944 Turbo, '88 924S (x2), '02 Boxster, '07 Cayman S, '73 914
Old 11-11-2017, 05:17 PM
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hey glademister - good work on figuring it out and getting it running - as to the stiff ride - my 84 also sat for a long time and when i first got it running and drove it the ride was very stiff - turns out the right rear strut was completely frozen and the 3 others had no resistance at all - after replacing all 4 struts the ride smoothed out considerably - also check the engine mounts, they also can make the car seem rough
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Old 11-12-2017, 09:46 AM
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Quote:
Originally Posted by stepson View Post
Glade,

You need to check your speed with those tires. IIRC, stock size is 225-45-16, so your tires will be taller with larger diameter. This will cause your speedo do display incorrect speed.

Might save you a ticket somewhere down the line
That is incorrect sir. OE tire fitment is 225x50x16. My speedo is reading correctly. That may not prevent me from getting that speeding ticket however LOL.
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Tennessee Region SCCA & PCA
Current projects - '85 928S, '87 924S, '82 931, '14 Cayman
Past projects - '72 Opel GT, '75 280Z, '90 300ZX, '87 944S, '87 944 Turbo, '88 924S (x2), '02 Boxster, '07 Cayman S, '73 914
Old 11-12-2017, 09:58 AM
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Quote:
Originally Posted by honerboys View Post
hey glademister - good work on figuring it out and getting it running - as to the stiff ride - my 84 also sat for a long time and when i first got it running and drove it the ride was very stiff - turns out the right rear strut was completely frozen and the 3 others had no resistance at all - after replacing all 4 struts the ride smoothed out considerably - also check the engine mounts, they also can make the car seem rough
Good tips. I suspect the dampeners will need replaced or refreshed at some point. Right now, I'm pretty happy with the ride. I like good suspension and steering feedback. Those plush seats are a real joy also
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Tennessee Region SCCA & PCA
Current projects - '85 928S, '87 924S, '82 931, '14 Cayman
Past projects - '72 Opel GT, '75 280Z, '90 300ZX, '87 944S, '87 944 Turbo, '88 924S (x2), '02 Boxster, '07 Cayman S, '73 914
Old 11-12-2017, 10:01 AM
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Window regulator swop

Yesterday I went into the passenger door to see if I could get the window regulator motor functional. Pulling the door card wasn't too bad and I only broke one piece of plastic - a small piece of the air duct. Clamped the window in the raised position and pulled out the regulator assembly. I figured out the motor was definitely seized up by testing with a 12V battery. Out in my parts storage I had both window regulator assemblies from a 924S and I was hopeful the motor would be compatible. When I bolted the 924S motor to the 928S window regulator I found that the little gear box had a slightly different dimension. Where the gear protrudes it has a longer shaft. So I separated the 928S electric motor from the gear box and tried putting the good electric motor from the 924S on that. That didn't work so well. Firstly, it's very difficult to get the worm gear shaft on the motor to spline up with the nylon drive gear in the gear box. When I did finally get it to seat well, the more I tightened the screws holding the motor to the gear box, the less able the motor was to function. Something was causing it to bind up. I used some washers for shims and kept bench testing but when I put the assembly back in the door and used the switch circuit, no dice. However, if I just jump the motor terminals to a battery, it will raise and lower the window. I suspect the switch is bad and noted that those switches have been swopped from one position to another. The switch in the passenger window position is labeled as a sun roof switch. I went ahead and buttoned everything back up as this issue is low priority but I'll need to get that switch out and see if I can clean it up or replace.



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Tennessee Region SCCA & PCA
Current projects - '85 928S, '87 924S, '82 931, '14 Cayman
Past projects - '72 Opel GT, '75 280Z, '90 300ZX, '87 944S, '87 944 Turbo, '88 924S (x2), '02 Boxster, '07 Cayman S, '73 914
Old 11-13-2017, 06:02 AM
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Quote:
Originally Posted by The Glademister View Post
That is incorrect sir. OE tire fitment is 225x50x16. My speedo is reading correctly. That may not prevent me from getting that speeding ticket however LOL.
Well, I guess I have CRS or I just remembered wrong. 225x45x16 stuck in my head, but is, in fact, incorrect. I deleted my previous post so future generations do not get confused as well. Thanks for keeping me straight!
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Old 11-13-2017, 09:43 AM
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Another successful fix

So I got another package from Roger with the odometer gear and replacement instrument bulbs. Tuesday was a day off after a medical procedure and I proceeded to pull the instrument cluster following this thread...

https://rennlist.com/forums/928-forum/520661-odometer-repair-procedure-w-pics-2.html

Very helpful and detailed. When I got he instrument panel out, I took it inside to my office desk for brain surgery. Everything came apart as planned and the old gear had basically distintegrated into dust. Cleaned that up, installed the new gear and tested. I did have some binding as noted in the thread but was able to solve that by pushing the axle the small gears for the trip tumblers back a tiny bit to one side. I changed out all the bulbs even though the originals all metered out as good. What I did find however, was the dimmer was corroded and not passing any current. I tried to clean that up but it was too far gone. Frankly, I couldn't even find the dimmer until I was taking the pod apart (I don't think that's anywhere in the owners manual). Anyway, I got the instrument panel back in, the turn signal switch assembly, covers, steering wheel all back on after a couple of attempts. I basically did a bypass on the dimmer. It was hard to tell if the instrument lights were working when I went for the daytime test drive but the odometer was. Then later that night I came back out and confirmed the instrument lights were working. Now it won't be so disconcerting driving at night.
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Tennessee Region SCCA & PCA
Current projects - '85 928S, '87 924S, '82 931, '14 Cayman
Past projects - '72 Opel GT, '75 280Z, '90 300ZX, '87 944S, '87 944 Turbo, '88 924S (x2), '02 Boxster, '07 Cayman S, '73 914
Old 11-16-2017, 07:14 AM
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while my panel dimmer does work i can't imagine when i would want to use it - the panel lights on these cars are adequate... but not by much
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Old 11-16-2017, 08:42 AM
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Quote:
Originally Posted by honerboys View Post
while my panel dimmer does work i can't imagine when i would want to use it - the panel lights on these cars are adequate... but not by much
Barely adequate but better than pitch black
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Tennessee Region SCCA & PCA
Current projects - '85 928S, '87 924S, '82 931, '14 Cayman
Past projects - '72 Opel GT, '75 280Z, '90 300ZX, '87 944S, '87 944 Turbo, '88 924S (x2), '02 Boxster, '07 Cayman S, '73 914
Old 11-16-2017, 09:22 AM
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