Need help guys 2.3ng

xxErix · 23-12-20, 10:55 AM

Hello

So, I daily drive a Audi coupe 80 B3 2.3ng, 1990, i have changed bunch of parts, and basically just doing it up to the way I see it... it has been running a bit rich, and idle has been a bit rough but nothing crazy.
But two days ago, I went for a shopping trip, and then outside the store, I started it, and it was barely running, and when I pressed the throttle, it just died, and after a few times trying it, worked fine. (also I noticed that the radiator FAN has been on all the time, I think its the coolant temp sensor, which has been ordered)
So for the rest of the day its running fine, until same thing happened in evening.
Yesterday, again seem to be okay for most part, untill later on in a day, and when driving home in evening, I noticed that the throttle is not as responsive, like I will press it half way, and it will barely pick up, and then when i press it more, it just goes almost like wide open.

anyone has experienced anything like it? any help would be appreciated,

also anyone know where I could possibly get Kjet tunned so its not running as ritch?

Thank you

mikes2 · 23-12-20, 12:55 PM

The temp sender for the fan is at the base of the radiator and will not affect the engine running issue.

Are you sure it's fuel ?

The ignition leads, rotor arm, plugs, distributor cap and timing are all good ?

I had similar issues with my 90 running K-JET. It was a combination of bad connections and timing / mixture adjustment.

It was the vacuum switch on mine which was preventing cold enrichment - just bad contacts.

xxErix · 23-12-20, 01:53 PM

well, when it was struggling to run, it was also smoking white smoke and smelling like petrol, so we were thinking its something to do with that, but again, dont really know, I just went for a drive, seem to idle ok for most part, maybe a bit low at times, and did seem to pull alright, takes a bit longer to start though

mikes2 · 23-12-20, 05:06 PM

Petrol smoke is usually grey. White I would expect to be coolant.

Does the oil smell of petrol and at a high level ?

xxErix · 27-12-20, 11:43 AM

when it was smoking, it was smelling properly of petrol, ive not really smelled the oil,

weirdly, yesterday , when it was cold it was runing fine, then did like 20mile drive, stopped for 1h or or so, and then when I started it, it struggle to idle for 1-2mins, and when i just put the foot down, after a few seconds of revving it seems to go back to normal, really odd

also , my fan is on all the time, ive changed the coolant temp sensor, but it still seem to be on all the time? is there any more sensors or something?

Isimmo · 27-12-20, 11:57 AM

Silly question, not a dodgey batch of fuel is it? I’ve had that before with similar results. And, the rallycar is currently laid up so the fuel (with stabiliser) is getting old and that’s now lumpy with grey smoke due to dead fuel.

xxErix · 27-12-20, 12:12 PM

to be fair, that kind of has crossed my mind, but what are the chances of that happening? haha

Isimmo · 27-12-20, 12:54 PM

Weeelll, they’re selling less and it’s rather wet out there...

I’d be tempted to put a couple of gallons in and some fuel injector cleaner. Won’t hurt either way.

John. · 27-12-20, 01:56 PM

How old is the fuel filter?

Mike has suggested you check the HT side of things, even if you can't check the resistance of the leads it'd be worth removing the leads from the cap and checking for corrosion at the ends, likewise at the coil and plugs.
A visual check of air pipes and hoses as well as electrical connections to the various fuel related parts ?

Duffy3074 · 28-12-20, 09:50 AM

If it’s starting poorly and smelling of petrol at that point I’d be thinking that it’s getting enriched at start up when both hot and cold.
When it’s cold, it needs that extra fuel so runs happily, when hot it doesn’t so runs like a pig, when you touch the throttle you add more air and more fuel and it stalls.
I suspect you’ve got a fuelling issue.
If the problem was only at start up and it was running well otherwise, then it’s just the autoenrichment (the autochoke for want of a better term) if running poorly all the time then either it’s set too rich or there’s a fuel system problem in done other form (failing component, air leak, etc etc)

23-12-20, 12:55 PM	#2
mikes2 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Polmont Posts: 2,617	The temp sender for the fan is at the base of the radiator and will not affect the engine running issue. Are you sure it's fuel ? The ignition leads, rotor arm, plugs, distributor cap and timing are all good ? I had similar issues with my 90 running K-JET. It was a combination of bad connections and timing / mixture adjustment. It was the vacuum switch on mine which was preventing cold enrichment - just bad contacts. __________________ 1991 90 quattro 20v sport 1991 90 quattro

23-12-20, 05:06 PM	#4
mikes2 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Polmont Posts: 2,617	Petrol smoke is usually grey. White I would expect to be coolant. Does the oil smell of petrol and at a high level ? __________________ 1991 90 quattro 20v sport 1991 90 quattro

27-12-20, 11:57 AM	#6
Isimmo Super Moderator Classic Audi Club Member Join Date: Jul 2007 Location: Sissix-by-the-sea Posts: 15,218	Silly question, not a dodgey batch of fuel is it? I’ve had that before with similar results. And, the rallycar is currently laid up so the fuel (with stabiliser) is getting old and that’s now lumpy with grey smoke due to dead fuel. __________________ 1985 WR quattro, 1985 20vT RallyRep, 1993 MTM ABY S2 Avant. 2010 S3 Sportback.

27-12-20, 12:54 PM	#8
Isimmo Super Moderator Classic Audi Club Member Join Date: Jul 2007 Location: Sissix-by-the-sea Posts: 15,218	Weeelll, they’re selling less and it’s rather wet out there... I’d be tempted to put a couple of gallons in and some fuel injector cleaner. Won’t hurt either way. __________________ 1985 WR quattro, 1985 20vT RallyRep, 1993 MTM ABY S2 Avant. 2010 S3 Sportback.

23-12-20, 01:53 PM	#3
xxErix Grown up member Join Date: Jun 2015 Location: Leeds Posts: 31	well, when it was struggling to run, it was also smoking white smoke and smelling like petrol, so we were thinking its something to do with that, but again, dont really know, I just went for a drive, seem to idle ok for most part, maybe a bit low at times, and did seem to pull alright, takes a bit longer to start though

27-12-20, 11:43 AM	#5
xxErix Grown up member Join Date: Jun 2015 Location: Leeds Posts: 31	when it was smoking, it was smelling properly of petrol, ive not really smelled the oil, weirdly, yesterday , when it was cold it was runing fine, then did like 20mile drive, stopped for 1h or or so, and then when I started it, it struggle to idle for 1-2mins, and when i just put the foot down, after a few seconds of revving it seems to go back to normal, really odd also , my fan is on all the time, ive changed the coolant temp sensor, but it still seem to be on all the time? is there any more sensors or something?

27-12-20, 12:12 PM	#7
xxErix Grown up member Join Date: Jun 2015 Location: Leeds Posts: 31	to be fair, that kind of has crossed my mind, but what are the chances of that happening? haha

27-12-20, 01:56 PM	#9
John. 4 ring whore! Classic Audi Club Member Join Date: Mar 2011 Location: Scottish Borders. Posts: 7,520	How old is the fuel filter? Mike has suggested you check the HT side of things, even if you can't check the resistance of the leads it'd be worth removing the leads from the cap and checking for corrosion at the ends, likewise at the coil and plugs. A visual check of air pipes and hoses as well as electrical connections to the various fuel related parts ?

28-12-20, 09:50 AM	#10
Duffy3074 4 ring whore! Classic Audi Club Member Join Date: Aug 2015 Location: Dalgety Bay, Fife Posts: 2,078	If it’s starting poorly and smelling of petrol at that point I’d be thinking that it’s getting enriched at start up when both hot and cold. When it’s cold, it needs that extra fuel so runs happily, when hot it doesn’t so runs like a pig, when you touch the throttle you add more air and more fuel and it stalls. I suspect you’ve got a fuelling issue. If the problem was only at start up and it was running well otherwise, then it’s just the autoenrichment (the autochoke for want of a better term) if running poorly all the time then either it’s set too rich or there’s a fuel system problem in done other form (failing component, air leak, etc etc)