924Board.org

sleepy · Joined: 29 Nov 2004 Posts: 63 Location: UK

can anyone give me the possible causes for a start problem with my 924n/a?
It took about 5 minutes to get it started today, I basically turned it over for 10 secs at a time while nudging the accelerator, wait 10 secs & repeat. eventually it starts to fire up getting about 7000 revs. for the next 30 secs it stutters before i can rev it properly. I take it a mile up the road to warm up & its idling better at 8000. I raced it back and it flies, & seems to be fine when i get back. I switched it off & theres no probs starting it after this.
There was a hell of a lot of heat coming from the manifold after, i don't know if this if normal?
Any help much apprecieated

-Sleepy
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meteor silver 1981 924 lux. -UK

chris24 · Posted: Mon May 23, 2005 6:10 am Post subject:

the manifold will get pretty hot after running. my old 924 used to need the accelerator right down and would start after about 10s cos the cold start injector (the blue one at the back of the manifold) and the auxillary air valve wouldn't work. The AAV just lets more air past the throttle wings, it is open when the engine is cold and so when you start it, it is holding down the throttle for you. There is the advice about checking the AAV and CSV on 924.org in the FAQ section. Good write-ups. CSV and AAV are the best place to start for cold start problems.
I guess you mean the idle at 800 not 8000..! You could turn the screw at the front of the manifold anti-clockwise a bit to make it idle faster at 950ish. This is just another bypass like the AAV.
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1983 - 924 (185K miles) - not mint
1985 - 924 (148K miles) - mint
1990 - 944S2 cab (52K miles)

chris24 · Posted: Mon May 23, 2005 6:15 am Post subject:

sorry, this is the link
http://www.924.org/techsection/GarageFAQ.htm#coldstart
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1983 - 924 (185K miles) - not mint
1985 - 924 (148K miles) - mint
1990 - 944S2 cab (52K miles)

sleepy · Joined: 29 Nov 2004 Posts: 63 Location: UK

Where exactly is that screw Cris? temporary fix would be good
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meteor silver 1981 924 lux. -UK

Ozzie · Posted: Mon May 23, 2005 7:22 am Post subject:

Idle should be about 950 for a manual and 1000 for an auto.
It is way to low at 700- 800 and would shake itself to bits or stall.

There is a screw on the throttle body next to the vacuum line going to the distributor. Use this to adjust idle.

Seems to be a cold start problem........ FAQ helps with this.
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Khal · Posted: Mon May 23, 2005 12:13 pm Post subject:

That's odd... my starting idle is 800rpm on the button and then settles to a warm idle at about 600-700rpm?

Is this normal for an '81 Turbo (has DITC)?

It's always had a lumpy idle but I thought it was maybe because it had a slightly beefy cam..?
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'80 924 Turbo

Joes924Racer · Posted: Mon May 23, 2005 3:36 pm Post subject:

To low. just a wee bit on the low side
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1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

falkon · Joined: 20 Apr 2005 Posts: 9

My starting idle goes wild jumping between 300 and 1300. It goes for about a minute before it normalizes at about 1100. Then in a few minutes it goes down to normal 950. Anybody else seen this behaviour?

Ozzie · Posted: Mon May 23, 2005 7:25 pm Post subject:

Mine did but the distributor was shot and had a vacuum leak.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance