AUDI A4 B8 QUATTRO ... 6CYL CALA ENGINE VIN 8K
MY A4 STUMBLES WHEN COLD AND PUT INTO GEAR. ONCE CAR IS
WARMED UP IT SEEMS TO RUN FINE. ENGINE ONLY HAS 95,000
MILES. HPFP CHANGED. ALL COILS AND PLUGS CHANGED. FUEL
PRESSURE SENSOR CHANGED. THROTTLE BODY CHANGED. MAP
SENSOR CHANGED AS WELL AS VACUUM LINES FROM AUDI. ALL
PARTS ARE OEM AUDI. CAR SOMETIMES HAS LOTS MORE POWER
THAN OTHER TIMES AND IF I GUN IT IT SOMETIMES GIVES A
DETONATION NOISE FROM UNDER HOOD .... PLEASE HELP IF
POSSIBLE .... IDEAS? MAYBE INTAKE MANIFOLD?
Detonation sound? If it is backfiring something is causing the timing to be way off.
only if I gun it like really hit the gas to the ground. The car drives fine otherwise. It almost seems like it's starving for oxygen. It doesn't backfire. I
its possible you have bad spark plugs and or coil packs. throwing parts at any car is not ussaly a good way to fix a car. I would imadgine this car has a turbo right ? if the car says 2.0T that means yes. Have the turbo serviced often lack of random power is the result of a tear in one of the 2 diframs attached to the turbo. It can also cause poor idle on warm up. the turbos need to be serviced every 80,000 km due to the nature of the high power engine and parts never last forever. have this checked out by your dealer i guesstimate a turbo rebuild or service should not cost more then 2000$ at the most. I don't know where about your at so this quote will likely not be a accurate price.
No. It's not turbo. 6 cal CALA engine. New plugs and coils. Maybe intake manifold is defective.
ok so i checked around a few forums seems the 3.2L engines get a carbon build up issue. the rough idle is likely due to carbon build up around the valves. you can have this checked out with a scope cam threw the spark plugs holes to see if its the case. so far for every 3.2L engine issue i have found regarding rough warm up time its been carbon build up. when they do it have the cyclinders checked for scoring as well. some engines have a recall issue with piston rings scraping the walls creating scors in the wall. high oil consumption is ussaly that sign tho.
I actually brought the car into my shop, disassembled the intake manifold and runners, cleaned out all the ports and valve stems, installed all new gaskets and torqued the bolts to spec. I also changed some vacuum hoses that leaked during a smoke test. I then reset the Throttle body with Vag Com VCDS. There aren't any codes other than an occasional injector 3 code that comes and goes without tripping the CEL. That was changed with new injector. I can run some diags on VAG and upload file. Just give me an idea which specs to look at in VAG.
sounds like the work has been going the direction of my train of thought hehe. any ways im mostly just looking for the read out of the fault codes. and I'm not sure you said that injector was replaced but that random trouble with the injector could be whats causing the lack of power and and detenation noise under the hood. I would start checking wires for signs of cracks or breaks same thing with the plug and signs of corrosion. as it sounds more like a improper voltage to the injector.
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