Posted September 14, 200915 yr comment_294658 Hey Z Car users, I have a stock 1978 280z .I just recently got the Spark plugs, plug wires, Dizzy cap and Rotor replaced. Followed with a timing. Under acceleration the intake makes a "pop" noise. I wa told the car was running lean. Has anyone ever had this problem? If you do, how did you fix it?thanks!-bee Link to comment https://www.classiczcars.com/forums/topic/33176-l28-has-a-intake-popping-noise/ Share on other sites More sharing options...
September 14, 200915 yr comment_294670 Did you have the work done to fix the popping problem or did this surface after the shop did the work? Did they actually adjust the timing or just check it?Intake pops after you goose throttle do usually mean lean with carbs. I'm sure it can mean the same with your car If you just had the plug wires replaced, start with the easiest and make sure your plug wires are installed correctly Link to comment https://www.classiczcars.com/forums/topic/33176-l28-has-a-intake-popping-noise/#findComment-294670 Share on other sites More sharing options...
September 15, 200915 yr Author comment_294770 Did you have the work done to fix the popping problem or did this surface after the shop did the work? Did they actually adjust the timing or just check it?Intake pops after you goose throttle do usually mean lean with carbs. I'm sure it can mean the same with your car If you just had the plug wires replaced, start with the easiest and make sure your plug wires are installed correctlyThe work was done with a fellow Z member. He brought over the timing gun and helped me timed it and also brought a mini tach to adjust the idle speed (800 rpms). When the car runs lean is it due to a weak pump , Im getting about 30 PSI when the car is off and about 32 or so when the car is running (the FSM shows that it needs a min. of 36.3psi )And the plugs are plugged in (counter clock wise) 1,5,3,6,2,4thanks again!-bee Link to comment https://www.classiczcars.com/forums/topic/33176-l28-has-a-intake-popping-noise/#findComment-294770 Share on other sites More sharing options...
September 17, 200915 yr comment_294972 Hey nice catch on the fuel pressure! That can definitely cause the lean condition, especially at higher rpm Link to comment https://www.classiczcars.com/forums/topic/33176-l28-has-a-intake-popping-noise/#findComment-294972 Share on other sites More sharing options...
September 17, 200915 yr Author comment_294989 Hey nice catch on the fuel pressure! That can definitely cause the lean condition, especially at higher rpm Thanks. We have come to a conclusion that the FPR is one of the problems (we pulled the vacuum hose off of the FPR and stuck a screw in it the pressure built up. Then we pulled the screw off and stuck it back into the FPR and the pressure dropped to around 24. I am going to order a new FPR and see where it goes then. Link to comment https://www.classiczcars.com/forums/topic/33176-l28-has-a-intake-popping-noise/#findComment-294989 Share on other sites More sharing options...
October 11, 200915 yr Author comment_297186 So I ordered the FPR and that is not the problem I am going to pull the FP out tomorrow for a quick clean and see what happens from there. Link to comment https://www.classiczcars.com/forums/topic/33176-l28-has-a-intake-popping-noise/#findComment-297186 Share on other sites More sharing options...
October 11, 200915 yr comment_297188 Run the valves first. Link to comment https://www.classiczcars.com/forums/topic/33176-l28-has-a-intake-popping-noise/#findComment-297188 Share on other sites More sharing options...
October 11, 200915 yr Author comment_297194 Run the valves first.Hey Z train thanks for the Reply, I am still new to the auto terminology. What does running valves mean? thanks! Link to comment https://www.classiczcars.com/forums/topic/33176-l28-has-a-intake-popping-noise/#findComment-297194 Share on other sites More sharing options...
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