Hot or Cold starting

moonwatcher · 29-03-16, 09:49 AM

Just a small problem, my Cq starts first time when hot OR cold will not fire up if warm, drive half a mile and stop and then it's a no go, leave it 1-2 hours and she's raring to go, any ideas or suggestions

andya · 29-03-16, 10:02 AM

Have you looked at the fuel pump relay? I had a similar problem on my cq. Gsf sell them at 26 ish quid.

Regards

moonwatcher · 29-03-16, 11:43 AM

I'll have a look later

leggy · 29-03-16, 12:07 PM

Hey moonwatcher

Not sure of the set up on the CQ, but I had the same problem with my 80 a while back

My ignition barrel had been sticky for a while, and well, I'd drive somewhere and would then have to wait until the engine had cooled down (or use jump leads) before my boy would start again; was a nightmare in the summer months when temperatures were souring I can tell you!

Well, after many months of trying to diagnose the problem to no avail, I then read something about cracked ignition switches causing restart issues, this being due to heat expansion preventing the switch from engaging properly when the engine is warm/hot. Ordered a replacement ignition barrel & switch, had it fitted, and well, a year or so later and the problem would seem to have been resolved.

This is my old switch:

Not only cracked but starting to fry too

- good job that I found that article when I did!

moonwatcher · 29-03-16, 06:58 PM

I first happened about ten years ago, I drove about half a mile, incoming mobile call, pulled into a lay bye, turned the engine off ( nice and legal ) and afterwards wouldn't start. It went perfect to AITP last year and last week drove about same distance, stopped for about 15 minutes and it happened again. Yesterday took her for a 10 mile run, stopped and started again perfect. As long as she is up to temperature or stone cold she works perfectly

leggy · 29-03-16, 07:33 PM

Mine didn't have the problem regularly to begin with moonwatcher...
was intermittent for quite some years before it became a real headache for me; being more noticeable like I say on warm/hot days.
Wish I'd have checked my switch sooner to be fair, would have saved me a whole heap of hassle, not to mention garage diagnostic bills and the embarrassment of having to flag down strangers every time I needed a jump start.

29-03-16, 10:02 AM	#2
andya Senior Member Classic Audi Club Member Join Date: Aug 2010 Location: Hampshire Posts: 1,149	Have you looked at the fuel pump relay? I had a similar problem on my cq. Gsf sell them at 26 ish quid. Regards __________________ 1985 Coupe Quattro 1986 Coupe 1.8 weber carb 1987 Coupe 2.2 GT

29-03-16, 11:43 AM	#3
moonwatcher 4 ring whore! Classic Audi Club Member Join Date: Jul 2008 Location: Barrow in Furness, Cumbria Posts: 2,049	I'll have a look later __________________ Coupe Quattro 1985

29-03-16, 12:07 PM	#4
leggy Senior Member Join Date: Nov 2014 Posts: 1,650	Hey moonwatcher Not sure of the set up on the CQ, but I had the same problem with my 80 a while back My ignition barrel had been sticky for a while, and well, I'd drive somewhere and would then have to wait until the engine had cooled down (or use jump leads) before my boy would start again; was a nightmare in the summer months when temperatures were souring I can tell you! Well, after many months of trying to diagnose the problem to no avail, I then read something about cracked ignition switches causing restart issues, this being due to heat expansion preventing the switch from engaging properly when the engine is warm/hot. Ordered a replacement ignition barrel & switch, had it fitted, and well, a year or so later and the problem would seem to have been resolved. This is my old switch: Not only cracked but starting to fry too - good job that I found that article when I did! Last edited by leggy; 29-03-16 at 12:30 PM.

29-03-16, 06:58 PM	#5
moonwatcher 4 ring whore! Classic Audi Club Member Join Date: Jul 2008 Location: Barrow in Furness, Cumbria Posts: 2,049	I first happened about ten years ago, I drove about half a mile, incoming mobile call, pulled into a lay bye, turned the engine off ( nice and legal ) and afterwards wouldn't start. It went perfect to AITP last year and last week drove about same distance, stopped for about 15 minutes and it happened again. Yesterday took her for a 10 mile run, stopped and started again perfect. As long as she is up to temperature or stone cold she works perfectly __________________ Coupe Quattro 1985

29-03-16, 07:33 PM	#6
leggy Senior Member Join Date: Nov 2014 Posts: 1,650	Mine didn't have the problem regularly to begin with moonwatcher... was intermittent for quite some years before it became a real headache for me; being more noticeable like I say on warm/hot days. Wish I'd have checked my switch sooner to be fair, would have saved me a whole heap of hassle, not to mention garage diagnostic bills and the embarrassment of having to flag down strangers every time I needed a jump start.