Hi everyone. I recently purchased a 1981 280zx and there's just a few problems with it that I would love to get input on.

I got it insanely cheap, only about $1200. the guy I bought it from thought it had a rod knock, but I think its just the injectors, which he put in himself and I don't know if I trust it. When its on, there's a really loud clicking sound coming from one of the back 3, but it does not sound like a rod knock as it was pretty high up on the block and I don't loose oil pressure under acceleration. Am I right in my assumption that its an injector?

This brings me to my second question, how do I make it run better? It was running really rough, probably has a misfire, not much acceleration and would not go past 45mph. as soon as I got home, I replaced the spark plugs with some NGK plugs, gapped to about .041-.042. after pulling the old ones, some were gapped smaller and some bigger. I thought this would solve the issues, but it did not. I even pulled each wire off while running and there was no change in engine speed. I then pulled off # 2 and 3 wires and absolutely no change there. Im gonna do a compression test this weekend and also see if I can check valve clearances and make sure those are good. I do have a theory, I think that the injectors might be causing these problems. He said he put them in himself, and I just don't know if I should trust it.

I would appreciate any help on this matter! Ive always wanted a Datsun but they've been way too expensive! So im relatively new to these cars and would love to learn any troubleshooting info or how to make this rebuild easier. Thank you!

 

The loud ticking could be a valve. Also, if the car was really neglected that badly it's possible one or more of the rocker arms have loosened completely, I've seen them fall off before no joke.

Could be a million different things, but yeah you're gonna want to adjust those valves either way. Should be done somewhat regularly anyway, but the way it sounds I doubt anyone has touched them in a looong time.

 

Thank you! I'll definitely check that out this weekend! The car does have just about 200,000 miles and I doubt they've been gone through in quite a while. Hopefully I don't see anything too worrying. Might also look at the injectors cause why not it cant hurt, hopefully good as new until the next problem!

 

luckily the L28 is damn near bulletproof. Even if something has gone wrong, I'd be amazed if it wasn't a simple fix.