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View Full Version : Periodic no start but cranks (when warm) then fuel smell



ORcoast
12-26-2012, 12:59 PM
Good day all.
I am new to Audi but did a little homework before buying my 2002 A4 3.0, 6 speed quattro. Love the car and was not supprised to have a code or two. Car just went over 50k (miles) and sometimes throws a cooling system code and is now developing a no start issue when the car is warm then parked for a bit. With what I have read here it appears to be related to the CTS but I will report my code buddy shows the temp at 198+\~ a deg or two once up to temp at hwy speeds on a cool normal Oregon day. I am preparing to change te sensor this week but am curious as it appears to be working but I cannot verify if it is accurate. How does this potentially affect the start issue I have ( almost smells like an ol carb engine when flooded ). My sense tells me it must have some to do with the map thinking the engine is a different temp than actual thus incorrectly compensating the fuel air in the start cycle. I am wondering if there is other symptoms I should look for as well as while I'm in under the hood and parts are an hour away I want to make the most of my time. The car has had regular service by the previous original owner which I verified at the dealer which serviced it and judging from the immaculate condition of the whole car I do not believe she has been neglected in any way. Almost forgot. The code was 1296
Also I notice that it sometimes idols a little rough. Sounds ok but you can feel it

Thanks in advance for any input.
Dan

AudiA4MickC
12-26-2012, 07:51 PM
could be the temp sensor throwing off the map. a scanner would show temp and you could compare to a hand held temp gun at the sensor location. also hold the pedal to the floor to get rid of the flood condition. after half throttle, the fuel supply is shut off. this is by design.

ORcoast
12-26-2012, 08:01 PM
Thanks for the tip. I will be changing it tomorrow. I had my scan tool hooked up and watched the temp move around a bit more than what I would expect. What temp it it when the needle is straight up on the dash? I did note it goes up to center and stayed pretty close even with a 20 deg swing on the scanner. The signal seems noisy to me

AudiA4MickC
12-27-2012, 02:58 PM
the sensor for the guage is NOT the sensor the MAP uses. The sensor for the guage should be straight up dead center when warm and sounds like it is working. the sensor for the computer in my 99 a4 2.8 is on the top back center of the engine against the firewall and is buried. the vaccum plate on top must be removed with 3 screws to change it. how about your IAT (intake air temp sensor) read? that would really throw the MAP for a loop if that is out. also check ALL those little vaccum hoses on the top of the engine. a vacuum leak would cause poor idle conditions and crummy starting. those hoses get baked quick and are most likely brittle or gewey and leaking.

ORcoast
02-10-2013, 07:00 PM
Sorry for the delayed update. I changed the temp sensor which with my large hands was a bit of a challenge but no worse than working on gas turbines. It cured the issues listed above. 5000 miles so far without a single hiccup. Even runs better :) Now onto getting an iPod to work with symp II. Will be looking at the audio threads next
Thanks for your inputs.