Major 4000s issues

250sx

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well up to this point noone has been able to figure this out on other forums so lets see if you guys can help

Ok Audi ran like crap for a month before we got some parts to try and fix it. Would take 15+ start-ups when cold to actually keep it running, and had to drop 2 gears on any hill, couldnt go more than 40mph on the hills I used to do 70-80mph on. Changed the fuel filters also. Found out the O-Ring between the fuel distributer and air box assembly was shot so we replaced that, still ran aweful so we also replaced the fuel distributor. Here is where it gets weird to us.

The two screws that hold the distributor on to the air box we can crank down on and tighten, but if we do the car wont run/start, but back them off 1/2 turn and it will run fine. This would be alright but when you run it from point a to b the screw loosens and makes it run worse and even unable to start once shut off.

Another thing we noticed is when you first start it up it will rev to 2k because of it being cold, but once warm it will spike between 800 RPMs and 1200 RPMs

Now today we started it probably the first time in 2 weeks and the sucker popped off in 2 spins of the starter and ran awesome. Seemed to have all the power it used to, shut it down after a 5 or so minute ride and would not start up. Wont even show any RPMS on the tach.


Points
New fuel distributor
New filters
Cold start valve works beautiful
Injectors spraying fuel
New plugs
Cannot tighten the 2 flat head screws on the distibutor without it shutting off
 
since we are in the UK 4000s is a Audi Quattro to us?

What year is your model and engine

Have you got any pics?
 
Yeah I think it would be. Its an '84 4000s (4 cylinder non turbo) and no i have no pics. lol its silver and is a coupe

also a little bit more info, it started tonight and ran for about 10 seconds then died. now its impossible to start
 
Bit confused by the distributor comment do you mean Air Flow meter on Air Box?.loosen screws and she runs fine that does not make sense to me sorry?

What CC is the engine and do you know what type of injection system

if the car only ran for 10 seconds and other faults seem to point to fuel related issues have you started from scratch i.e fuelpump>relay>filter>air flow meter > pressure tested the injection system >injectors>ISV >lambda probe
 
its a 1.8L Mechanical injection system.


And by the distrutor comment I mean just that, the fuel distibutor. The distributor sits on the air flow meter, there are 2 screws which hold it to the air flow meter (they actually hold it onto the vehicle).

We have done everything up to ISV and lambda probe. What are these?
 
And to help further Steve...

4000= Audi 80/Coupe (Sharing most of the same parts, 4 cylinder is non quattro, unless its the standard 4 door 80 saloon. 5 Cylinder Coupes were quattros, although the most that I knew were all front wheel drive only, quite a rare beast the non turbo'd 5 cylinder quattro.The 80 4 door saloon started out as a 5 cylinder quattro before dropping down to the 4 cylinder 1.8 Golf engine. )

Therefore, its more probably a digifant 1.8 engine...
 
I used to have a type 89 1.8 with k jetronic, it was a 1987 car which did not come with a catalyst in UK.
An ISV is Idle Stabilisation Valve, it's an electrically operated valve that maintains correct idle speed. Only cars with an ECU have them. My 1.8 did not have an ecu or ISV, it used a more basic system that altered the ignition timing to prevent stalling. The only times my car had idle problems, were once when the mixture was too weak, and another time there was a cracked hose going to the throttle body (vacuum leak). symptoms were as you describe, 8-1200rpm idle when warm.
A Lambda probe is an O2 sensor, which controls mixture on cat equipped cars. A bad O2 sensor can cause bad idling, and poor fuel consumption, because it usually causes the car to run rich. The signal from the O2 sensor is usually not used when the car is not fully warmed up. So it would not be the cause of cold running problems.
It sounds like you may have a few minor problems like vacuum leaks, but the big one has to be that fuel distributor. I don't qite understand what you mean, regarding the 2 screws, but something is not right there, eg wrong part, something distorted/misaligned? Can you get hold of a complete metering head off a running car?
Only other thing I came across was a bad fuel pump relay, which sometimes stopped my car starting, sometimes made it cut out, but it did run normally when it was running!