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Gram

I've just finished adjusting the cam followers and replaced the oiler tube and elbow. Now the motor won't run above 700rpm at full throttle, and cuts out if I let go the accelerator. Nothing was adjusted or dismantled except releasing the accelerator cable from the stop, and removing the distributor cap for a little more room, but they were put back as they were before. I've checked the timing, made sure the air sensor plate isn't jammed, the throttle butterflies are opening properly and I've replaced the fuel pump relay with a jumper to make sure it isn't the relay/pump. All the plug leads are OK and it runs evenly, just smells rich and won't rev. The car has been sitting for 2 weeks but ran fine before, and idled at about 900rpm. Any ideas please?
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

Ozzie · Posted: Mon Jul 04, 2005 1:30 pm Post subject:

Aux Air Valve.
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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

Crazyd96 · Joined: 04 Jul 2005 Posts: 5 Location: Lodi, Ohio

Read my post about my 1978 924. Do you think my problem is similar to yours? Let me know if you find the problem.
-Dan Porsch924@aol.com
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Current Vehicles:
1978 Porsche 924
1990 Audi 90 20 Valve Quattro
2001 Audi A6 2.8 Quattro
1977 Chevrolet K10
1966 Yamaha YDS-3

Gram · Posted: Mon Jul 04, 2005 2:45 pm Post subject:

Not sure if we share a similiar problem, but I'm suspecting my distributor..maybe it's time it was overhauled. Perhaps your problem is ignition too.
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

Gram · Posted: Mon Jul 04, 2005 2:49 pm Post subject:

Why the AAV Ozzie? The motor will warm up OK, but only at idle and won't rev. The AAV only works if the engine is cold anyway.
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

Ozzie · Posted: Mon Jul 04, 2005 5:19 pm Post subject:

Ok - not enough info in the first post or I misread.
Check the pickup in the dist. and wiring down to ign control module.
Coil resistance.
Sounds like a weak spark.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Gram · Posted: Tue Jul 05, 2005 6:21 am Post subject:

Yeah, I think yr right Ozzie..that it's ignition rather than fuel. Can the four-pointed metal thingy under the rotor slip, or is it keyed somehow onto the distributor shaft? I haven't taken off the circlip yet to have a look, but I can't see how it can slip. Is the clearance between the metal rotor and the stator in the side of the distibutor body critical?
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

Ozzie · Posted: Tue Jul 05, 2005 7:12 am Post subject:

The 4 point unit is connected to the advance mechanisms.
The little coil pickup have been known to fail, check resistance, I think it is about 80 ohms.
There should be a circuit to the ign module and to the main coil.
Did you remove the plug leads and put them back in the correct firing order. 1432?

No 1 lead should be above the small notch on the dist. housing next to the cable entry for the pickup.
The rotor should be pointing towards it when at TDC.

Did you remove your cam wheel?
These can be fitted on backwards and I have known people to do it.
This would throw valve and ign timing off.
The dot on the wheel should be on the firewall side.

As long as the 4 points dont hit the clearance is ok.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Gram · Posted: Tue Jul 05, 2005 8:01 am Post subject:

Didn't touch the plug leads, cam wheel, belt etc. Only removed the dist. cap to get the leads out of the way when I took the cam cover off. I've checked and rechecked everything I can think of. Maybe the coil or sender in the dist. decided to pack it in, but my multimeter is out on the boat..grrr.
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

Ozzie · Posted: Tue Jul 05, 2005 9:08 am Post subject:

That can make it awkward.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Gram · Posted: Tue Jul 05, 2005 5:58 pm Post subject:

Too stormy to row to the boat so I might buy another DMM tomorrow, and a friend is loaning me a 924 distributor to try. If that doesn't work I'll start checking the fuel system from the pump on..Can the pressure regulating piston in the fuel distributor stick open?
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

Ozzie · Posted: Tue Jul 05, 2005 6:06 pm Post subject:

About the only thing I haven't touched is the fuel distributor.
My philosophy- If it ain't broke don't f*&k with it.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Gram · Posted: Tue Jul 05, 2005 6:11 pm Post subject:

Yeah..my sentiments too, but I'm running out of ideas.
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

D Hook · Joined: 02 Nov 2002 Posts: 3158 Location: Omaha, NE

Have you checked the small wire that runs into the side of the distributor for a good connection at both ends? I've heard that can come loose and cause an intermittent problem. I think if I were you I'd check very closely everything you touched before moving onto other systems that weren't involved in the original repair. Esecially check the electrical connections again. I had a slight miss that turned into a bigger miss and couldn't find anything until I took a close look at my coil wire, found a cut in the jacket and saw where it had been arcing to the hood of the car. The cut was very small and hard to see but sure caused a big problem.
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'80 924 n/a SOLD

dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

How did you adjust your valves? It sounds like the exhaust valves are too tight, causing a loss of compression and vacuum for advance.

Dennis
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78 928 5 sp Silver
78 928 AT Euro Black