924Board.org

[RVA]

So i just got my 924 (1981 eu model) running after a few months of working on it. However i doesn't run well. If i don't keep my foot on the throttle its at like 500 rpm and wants to die, it sometimes does die. So i have to keep my foot on the throttle. At 2000 - 3000 rpm it runs quite well actually on all 4 cylinders.
But the throttle response is laughably bad. There is like a 2 second delay from when i hit the throttle and when the engine actually revs up, which makes it quite challenging to keep it at a steady rpm.

So far i have changed/checked:

Cleaned fuel tank + fuel lines
New filter
New fuel pump + relay
Fresh 98 RON fuel
Got injectors cleaned and tested
Rebuild the WÜR
Checked all the fuel pressures, all good
Injector/CIS output is good and the same on all 4.
Cold start valve is NOT leaking.
New spark plugs, new coil, new spark plug wires. Gapped plugs at 0,6mm
New rotor and distributor cap.
New starter motor
New battery
Replaced old fuel lines and old vacuum lines.
Checked engine timing
Set ignition timing (static, i haven't used timing light yet because engine is so hard to keep at steady rpm)
Tested basicly entire ignition system with multimeter (tests in hayned manual, all good results)
Compression test, all 4 cylinders at 10,5 bar / 150 psi.
Set the fuel mixture with adjustment screw, its as best as i can get it without CO2/AFR gauges.

I think thats all i did...

Anyways what are my next steps? I really wan't to start driving this thing, suspension brakes all that is in perfect condition

[morghen]

Next step is to pre-order a plug-in, bolt-on EFI kit from me.
Also a supercharger kit while you are there.

_________________
Supercharger and EFI kits
https://www.the924.com

[924RACR]

Throttle response that bad, I just can't believe the mixture/timing is right. Like WAY off.
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[RVA]

Well something is way off for sure, and the 2 seconds is maybe like 1 second but still you get the point.

I set the timing static so with all the marks on flywheel, distributor and camgear lined up so i assume that would be good for like a base tune until i get it running good enough to use my timing light? is that correct?

And the fuel mixture i started from the base setting (take of fuel line from CIS block, run fuel pump, and turn mixture screw clockwise until fuel just drips out of CIS block, then turn back half a turn) And then i adjusted it with engine running until there wasn't black smoke coming out of exaust, now its at a point where if i make it leaner it runs worse and if i make it richer it also starts running worse.

[RVA]

[Rasta Monsta]

Smoke test the intake
_________________
Toofah King Bad

• WeiBe (1987 924S 2.5t) - 931 S3

[morghen]

Take out the spark plugs and take pictures of them, make sure to know which came from which cyl.
_________________
Supercharger and EFI kits
https://www.the924.com

[ChrisMadge]

[RVA]

[RVA]

[RVA]

Important:

The camshaft pulley and the crankshaft pulley CANNOT move right? They are locked in place with a little pin right?(don't know what its called)

Because if they are not locked in place my timing marks could be off, if they are locked in my timing marks are correct.

[Mclaren924]

I know for sure the crankshaft pulley is keyed on, I also think the cam is too but I could be wrong so other guys can correct me if I'm wrong. You're using the rear marking on the cam shaft pulley correct? Also when doing electrical timing, did you line up the scribed mark in the distributor housing with the rotor and then use the rotor point for a base to start the spark plug order? Just confirming that everything is timed right so you can begin looking for other issues. Cheers
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1980 931 "Salt" Bucket wannabe racer (Dreaming)
1979 924 Sebring "Pepper" -Sold
1977 924 Slicktop "Pennie"-Most likely parts
1979 3/5 gt clone 924- Shop Test Car

[morghen]

They are both keyed in, but have some tolerance...worst case you are half a tooth off...would not cause your issues.

Lets see how those plugs look, and when did you change the ignition plugs/leads/rotor/cap last?
_________________
Supercharger and EFI kits
https://www.the924.com

[RVA]

Yes i am using the rear marking on camshaft pulley,

'did you line up the scribed mark in the distributor housing with the rotor and then use the rotor point for a base to start the spark plug order?' Yes i did


'Lets see how those plugs look, and when did you change the ignition plugs/leads/rotor/cap last?'
I am quite busy this week but ill take the plugs out and take pictures this friday/weekend
Changed ignition leads/plugs rotor and cap 2 months ago, car has only ran a few times since i replaced them, they still look good.

There is one more thing i can think of, but i don't know if this would cause my problems. Maybe someone knows the answer : https://www.924board.org/viewtopic.php?t=45990

[Nobbi]

could it be the vaccum advance of the ignition distributor? I the hose connected and working? Did you blow into the hose and see the advance working? And lube that little felt piece in the center....
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NA 924 - april/1977- 4-speed-audi gearbox.
500.000 km with fun.....and new toy:Porsche 944 S2 Cabriolet.Other car Daimler c-class cabby,brandnew..Plus : DEUTZ 4005 tractor Built 1967