UK Car Repair Questions? Ask a Mechanic for Answers ASAP
Hi, I’m Ron and I can help you.I have been in this business since 1975 and also teach automotive repair. I am confidentwe can resolve your problem together. Please understand that I don't know your skilllevel. I can't see, smell, hear, or touch the vehicle either, so it may take a few replies toget to satisfactory results. Please be patient!I also try to give all of the information you may need, expecting a “positive rating” inreturn. I will also continue assisting you after you have rated me, if necessary. If thereis any reason I cannot get a positive rating, please let me know why “in advance”, so Ican go another direction for you. I am sorry you’re having this problem; I’ll help youthrough it.
Most cleaners are great for maintenance only. It sounds like the long sit caused a varnish buildup and needs to be flushed from a machine with high power chemicals. The best thing to do when a car is going to be sitting, is to add fuel stabilizer so this doesn't happen again. Thanks, Ron
Ok, then check the EGR for being stuck in a semi open position this would cause a lean condition at idle and shuttering like you described. Don't forget to clean the intake and exhaust passages very good. If this is ok, then search out any other potential vacuum leaks such as at the PCV or brake booster. The best way to check for vacuum leaks is with water.
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