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JamesWilson · Joined: 10 Jun 2005 Posts: 132 Location: San Diego, CA

So the new wastegate is in, tubing repaired, and all set to go. Set at 9-11psi (stock 930 wastegate and spring), holds correctly on the gauge. Still stutters and hesitates past 4K rpm, but at least it gets there.

So I disconnected the overboost switch wire and grounded it, and then undid the timing retard clip just to see what would happen....ran like crap. Plugged the retard clip back in, car runs amazingly all the way to about 5100rpm, super-smooth power delivery and sounds great, but has a light cutout up top like its hitting a "soft" limiter, right around 5K rpm. The car used to do a fuel cutout at 15psi--- you think the switch is intermittantly cutting out the fuel pump at too-low pressures, as evident by the smooth running with the switch disconnected?

With the new exhaust I do want to take it back to use the exhaust gas analyser to see if its running lean up top, which is a possibility. We had it tuned with the stock cat and B&B exhaust (944 turbo) and stock airbox/filter, now running the K&N euro intake system and 3" high-flow cat/exhaust, may be leaning out again.

PCA event this Saturday, want to get it done and pick up some more VP Motorsport 109 and do it right!

-JamesW
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'82 924 Turbo (not stock) - soon returning home?
www.AffordableRacingData.com

WEASEL149 · Joined: 19 Aug 2005 Posts: 595 Location: UK, Sheffield

Paul · Posted: Wed Sep 07, 2005 8:50 am Post subject:

James,

What can you tell us about the Boxster brakes on your 931?
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White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

JamesWilson · Joined: 10 Jun 2005 Posts: 132 Location: San Diego, CA

Overboost switch is less than $20 my cost, but I will have to look into the WOT enrichment thingy----still havent gotten my Haynes manual, lost one in the mail via eBay and the other one is also MIA from AutoZone...time to call Performance Products and just eat the higher cost!

Ouch! $430USD new or $290usd plus 100 core charge! Is is possible that an air leak in the tubes to the WUR may be causing problems? Is there a way to clean the WUR and assist its function (old Honda EFI trick)?

-JamesW
_________________
'82 924 Turbo (not stock) - soon returning home?
www.AffordableRacingData.com

Lizard · Posted: Wed Sep 07, 2005 10:16 am Post subject:

there is no way there can be an air pocket to the WUR. as per cleaning it not really, and you will need a special guage to test it as well.
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3 928s,

WEASEL149 · Joined: 19 Aug 2005 Posts: 595 Location: UK, Sheffield

Paul · Posted: Fri Sep 09, 2005 11:38 am Post subject:

JamesWilson · Joined: 10 Jun 2005 Posts: 132 Location: San Diego, CA

I have an appointment Fri morning for the EGA machine and to tune the CIS-- invaluable if you have access to one, I would have never known that the car was running so lean initially! I think that with the exhaust and intake the car is further leaning out, I want to to see if I can fatten the mixture up before I replace the WUR.

I'll update tomorrow after driving the car around, I have about 30 min of track testing time in the afternoon and then the PCA autocross on Saturday.

-JamesW
_________________
'82 924 Turbo (not stock) - soon returning home?
www.AffordableRacingData.com

Tigger937 · Posted: Fri Sep 09, 2005 4:30 pm Post subject:

Have you considered the possibility of marginal fuel pumps? Have you had any problems with blowing the fuse to the fuel pumps, noticed the fuel pump relay getting hot, having excessive current draw or performed a fuel pressure check? I ask because I'm currently experiencing similiar symptoms at 5700 RPM although I don't have to be accelerating at full throttle. Just holding the RPM's constant at 5700 will give me the same symptoms. My mixture also appears to be running a bit lean on boost, however, I only have a NB O2 sensor to verify, so I don't have a lot of faith in the readings.

A few months ago, my fuel pump fuse blew for no apparent reason while driving on the highway. I replaced it and soon was on my way again and haven't blown another since. I believe my pumps are still original, but I am about to replace them in hopes of curing the problem. Haven't checked the WUR other than testing the vaccuum/boost line for leaks.............it was OK.
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1981 931 (Concours)
1982 931 (Daily Driver)

"Think outside the box"

JamesWilson · Joined: 10 Jun 2005 Posts: 132 Location: San Diego, CA

Just got back from Black Forest, numbers looked good on the EGA-- not lean at any rpm or on boost, but there was a misfire at idle and up high.....we discovered that one of the coil wires (one of the negative sides) was only connected by 1 or 2 strands! Not sure if its just the tach signal wire, as it needs very little input signal, as this was the slightly "thinner" gauge wire. I am cutting and putting new blade terminals on there, and checking the resistance of the coil (anyone have stock numbers for the Bosch coil?).

New plugs, wires, cap/rotor, disconnected the Jacobs OmniPack ignition system when I bought it, new Bosch O2 sensor, BIG engine and systems grounds, can't think of anything else.....I will probably replace the plugs again before the weekend, just in case. The guys also recommended a valve adjustment, but still I'm without a manual!!

-JamesW
_________________
'82 924 Turbo (not stock) - soon returning home?
www.AffordableRacingData.com