RB_eater

Alright time for an update. Sorry if I don't post so much but I can only work on my car during the week-ends as I'm in the military and currently undergoing infantry training. So I changed all the spark plugs and now the engine WILL start but will only idle if I keep it at full throttle. Anything less and it stalls. Right now I'm thinking one of two options; 1. The spark is weak and since the engine only idles (draws little fuel) and the throttle is wide open (alot of air) is creates a lean mixture that the weaker spark can ignite. Therefore is would be an electrical issue. Makes a lot of sense since everything started after I installed that battery guard device. 2. There is some other problem (most probably carburator related) that kept the engine from running correctly and somehow created enough dirt on the spark plugs to keep the engine from starting at all. Since I changed the plugs the engine will start but the root problem is somewhere else. I'll have more time tomorrow to work on the car. In the mean time if anybody has any ideas let me know. Thanks to everyone for the help so far.

I went and double checked the carb. It's indeed a Holley but I couldn't see any model number or name. Mechanical fuel pump. There is some fuel squirting out when I press the accelerator so I pump the pedal a few times and tried starting the engine. It didn't start so I tried again while keeping my foot on the pedal and I had a backfire. So I guess timing is also off? But from what the owner told me (and guessing by the 1k rpm idle) there is supposed to be an aftermarket cam in there which in turn could explain the advanced timing. Another thing I noticed is that there is quite a few capped hoses, making a vaccum leak very plausible.

I only have a single, 4 barrel carburator. Holley if my memory serves me right. As for the history of the car, it has been slightly modified and yes it has been sitting for extended periods of time. The last owner had it in storage for most of the year. I've had quite a lot of minor problems appearing because of that but most of them have been taken care of. Is there a good way to check if enough fuel is indeed making it to the engine? I know there is a decent amount flowing through but is it possible there is not enough? Sorry if I sound like a newbie but my other car has a turbocharged rotary engine in it so I've got a long way to go haha. And I'll try your idea for the battery drain, thanks.

Sorry if I wasn't clear enough, the car started redlinning when I pressed the clutch and released the accelerator. I already fixed that problem, it was a spring problem like beandip mentionned. However I'm woried the engine might have been damaged. Also the engine isn't starting. Just after the incident, while it was still hot, it would start but I had to go full throttle to keep an idle. Now that the engine is could it will not start anymore. I'll try a second compression check, I've got a cheapo tester and I'm pretty sure I forgot to open the throttle. Since I didn't know how high the numbers should be I was mainly trying to check if the compression was even between cylinders.

So I just did a quick compression check. All cylinders showed a reading of around 90-105 psi except one at 60 or so psi. I guess this isn't looking too good? I noticed all sparkplugs smelled gasoline and were pretty dirty, all the tips were black. I didn't have time to clean them up but could it be they are the problem? I also checked the oil, it's missing some and the engine is well overdue for an oil change. I suppose I should have checked that when I bought the car last week... So does anyone have an idea what the problem could be? Edit: I just checked a spark plug and there IS a spark so I guess the coil is fine, could still be one of the other 5 plugs though.

Hi guys I'm new here. I recently bought my first Z, a clean 1971 240Z, but I'm having some trouble with her. I have an electrical leak somewhere and untill I could get some time to find it I installed a battery guard. Now when I started the car I heard a spark of some sort but the engine started normally. A few blocks away when I pressed the clutch the engine started redlinning so I shut it off as fast as I could. While it was still hot the engine would start but I had to keep it at full throttle. Now that the engine is cold it won't start at all, almost does but it keeps stalling. I didn't have time to do a compression check yet but it doesn't seem blown, the engine was still smooth but it kind of looked like it wasn't getting enough fuel. I tried looking at the carburator but everything looked fine (although I can't say I'm particularly at ease with carburators). The filter was clean and there seamed to be enough fuel comming out. I also checked the choke. Is it possible it could be an electrical issue? The engine had barely 66000 miles on it some I'm hoping everything is still fine. If anyone could help it would be greatly appreciated. Thanks.