Hi all, I have a mk4 golf ARL 1.9 PD 150 which has a stutter/murmur when idling until it warms up to optimum temperature. The RPM doesn't drop or raise but I can feel as though it's "missing a heart beat" so to speak. I have some black smoke on start up but none after that. Bit of history on the car: - Previous owner had it tuned to 200 BHP, I de-tuned it with a stock map being re-installed about a year and a half ago. About a year ago I blocked off the EGR pipe from the exhaust manifold after cleaning the valve and inlet manifold which were stinking! Also put an oil catch tank on. I replaced all the intercooler pipes with allard aluminium pipes and put an allard modified Audi S3 Intercooler on. All stock other than that as far as I'm aware. What could be causing this murmuring, I'm worried it could be the injectors on their way out? Cheers in advance, Jon
Hmmm that last bit sounds like a job for a garage possibly. I'm putting it in to fix an oil leak and some other bits n' bobs so I'll see what error logs come up.
Is it possible (might be talking out of my ar*e here) that the warm up cycle requires the egr valve with the std map? My old isuzu trooper had a flap in the exhaust and one in the inlet to force the engine to warm up faster along with the egr valve using the exhast gasses backing up in the cylinders.
You might be right there cus that is another source of heat for the warm up cycle and the aluminium intercooler pipes would mean colder air for longer as opposed to plastic pipes being more of an insulater. Through the winter in the cold mornings they weren't the smoothest of cold starts despite starting first time.
could be couple things over the internet it's hard - either flywheel is on way out, timing on the cam isn't right, or injectors I''d go with the cam timing first - the bottom and the top need locking up, the top is a vernier and sub half a tooth makes a difference I have played with mine got it worse & better. Needs VCDS to get it spot on when tweaking poor idle and some loss of power can be the fuel pump in tank broke, and the one on the engine doing all the work - can you hear it prime before start up?
Well couldn't be the flywheel cus I had that changed as soon as I bought the car by the car sales people, I sourced the parts from darkside developments and I sourced the labour so no funny tricks there from the car sales. Very possible that the timing on the cam shaft is out after a big tuning on the engine. As for the fuel priming; yes it makes like a squirty noise when I turn the ignition to light up the coil. I'm having a few jobs done on the car soon at the garage so I'll get them to check the timing at the same time. Hmmm... This is starting to sound like a possible proverbial "needle in a hay stack" kind of thing! Good thing is its only a small problem, no tears to fall...as yet...
