mattausten23 Posted July 18, 2012 Share Posted July 18, 2012 (edited) I just started driving my car again after it's been off the road for a couple of months. It's been running good, but today while I was warming the car up, I noticed it sounded different. When I drove it the car was back firing and I felt like it lost a lot of power, I didn't even try to get on it because it didn't feel like it was revving right. I'm thinking maybe I have an exhaust leak since I lowered the car and the exhaust bottoms out sometimes, also I noticed once line is slowly leaking going to one of the carbs. My question is could these things be the problem? I'm thinking if it's an exhaust leak I wouldn't be loosing power right? Edited July 18, 2012 by mattausten23 Quote Link to comment Share on other sites More sharing options...
BluDestiny Posted July 18, 2012 Share Posted July 18, 2012 Old gas if its really been sitting that long. My 280zx literally wouldn't rev past 4k after I got it on the road after 5 months of jackstands. Exhaust leak wouldn't cause backfiring.... Quote Link to comment Share on other sites More sharing options...
mattausten23 Posted July 18, 2012 Author Share Posted July 18, 2012 Old gas if its really been sitting that long. My 280zx literally wouldn't rev past 4k after I got it on the road after 5 months of jackstands. Exhaust leak wouldn't cause backfiring.... Mine has been sitting for about 3-4 months, so that might be it. Would that cause backfiring? Quote Link to comment Share on other sites More sharing options...
Lazeum Posted July 18, 2012 Share Posted July 18, 2012 (edited) I would suspect ignition problem: either your timing is way off, your alternator is going bad (the unit itself or some connections), your dizzy is worn out or something is going bad with your spark plugs/wires. Start by easy stuff such as spark plug inspection, if they are fouled, change them. Your problem could be that simple. However, you would have to understand why they are fouled afterwards (lot of cold starts or cold start mechanism not ok could be some of the reasons for instance) Have you played with ignition wires? are you sure to still have proper firing order? Can you move the base of the dizzy by hand? - if timing is off, something is probably loose. Is your alternator belt ok with proper tension & shape? Check voltage on your alternator? do you see battery voltage going up between engine stopped & running? Have you checked for leak around carbs? take a fuel hose, one end to your ear & chase leaks with the other end around the carbs & manifold. You could also try to spray carb cleaner where you could have leaks, it would make the engine run faster if you have a leak (clean a little your intake first if you don't want to have the dirts being sucked). Regarding gas, my Z sat for 2 years while I was rebuilding my engine & restoring my suspension, it started right up with 2 years old gas. I don't think it should be your focus. For your exhaust leak, it would make noise, it would vibrate but I doubt it would create the symptoms you're describing. Edited July 19, 2012 by Lazeum Quote Link to comment Share on other sites More sharing options...
mattausten23 Posted July 18, 2012 Author Share Posted July 18, 2012 I would suspect ignition problem: either your timing is way off, your alternator is going bad (the unit itself or some connections), your dizzy is worn out or something is going bad with your spark plugs/wires. Start by easy stuff such as spark plug inspection, if they are fouled, change them. Your problem could be that simple. However, you would have to understand why they are fouled afterwards (lot of cold starts or cold start mechanism not ok could be some of the reasons for instance) Have you play with ignition wires? are you sure to still have proper firing order? Can you move the base of the dizzy by hand? - if timing is off, something is probably loose. Is your alternator belt ok with proper tension & shape? Check voltage on your alternator? do you see battery voltage going up between engine stopped & running? Have you checked for leak around carbs? take a fuel hose, one end to your ear & chase leaks with the other end around the carbs & manifold. You could also try to spray carb cleaner where you could have leaks, it would make the engine run faster if you have a leak (clean a little your intake first if you don't want to have the dirts being sucked). Regarding gas, my Z sat for 2 years while I was rebuilding my engine & restoring my suspension, it started right up with 2 years old gas. I don't think it should be your focus. For your exhaust leak, it would make noise, it would vibrate but I doubt it would create the symptoms you're describing. Thanks a lot for all the info! It does sound like an ignition problem because it doesn't sound like it's firing correctly. I put new NRG spark plug wires on when I first got the car which was about a year ago and the car was running fine then. Today I fixed a leaky line that was going to the carburetor and can't seem to find any more leaks yet. It's just weird because the car was running good when I first got it back on the road I believe 3 days ago, and this problem just happend yesterday. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.