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Hello Everyone,

I just picked up this 280zx as a project to work on with my son. It needs quite a bit of work but I know with some hard work we will be able to bring this one back to life! I am new to Z's but have wanted one for years. We were able to get it running over the weekend, but it is not running well and has a pretty bad exhaust leak at the manifold. I am in South Texas, so if there is anyone is the Corpus Christi area please reach out.

Thank you,
Gary

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Exhaust manifold leaks are common on the L6 Z-cars, usually because of broken studs at the ends of the manifold. They are famous for heat-fatiguing and breaking off, leaving the manifold leaking at the ends. You'll hear a ticking sound or something similar when this happens.

Many times the studs are stuck in the head so badly that the head needs to come off to remove them. I had one that ended up requiring laser removal of the broken stud. But maybe, just maybe, they can either be drilled and backed out of grabbed and removed.

Because of the potential for badly stuck studs, unless something else requires you to pull the head or the engine, I suggest you live with that problem for now. It doesn't hurt anything to let the manifold leak slightly, and pulling it is a substantial job. If you have to pull the engine for some reason, you'll have good access to the manifolds. I found them extremely difficult to remove the manifolds without pulling the head. Some of the bolts involved secure both the exhaust and intake manifolds at the same time.

If you need to pull the engine or the head, for heaven's sake get a shop manual and do it by the book. Basic stuff is easy to miss, like the need to have #1 cylinder on TDC and timing the cam and timing chain correctly. You also have to assemble the timing chain covers in the correct order or it's tough to get the gaskets to seal.

Hopefully that's all advice you won't need. The car looks good, so enjoy it. They're not hard to work on.
 

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Discussion Starter #3
Exhaust manifold leaks are common on the L6 Z-cars, usually because of broken studs at the ends of the manifold. They are famous for heat-fatiguing and breaking off, leaving the manifold leaking at the ends. You'll hear a ticking sound or something similar when this happens.

Many times the studs are stuck in the head so badly that the head needs to come off to remove them. I had one that ended up requiring laser removal of the broken stud. But maybe, just maybe, they can either be drilled and backed out of grabbed and removed.

Because of the potential for badly stuck studs, unless something else requires you to pull the head or the engine, I suggest you live with that problem for now. It doesn't hurt anything to let the manifold leak slightly, and pulling it is a substantial job. If you have to pull the engine for some reason, you'll have good access to the manifolds. I found them extremely difficult to remove the manifolds without pulling the head. Some of the bolts involved secure both the exhaust and intake manifolds at the same time.

If you need to pull the engine or the head, for heaven's sake get a shop manual and do it by the book. Basic stuff is easy to miss, like the need to have #1 cylinder on TDC and timing the cam and timing chain correctly. You also have to assemble the timing chain covers in the correct order or it's tough to get the gaskets to seal.

Hopefully that's all advice you won't need. The car looks good, so enjoy it. They're not hard to work on.
I appreciate the information. I hope that I don't have to go to that extreme but I guess I will find out at some point. The first issue before I tackle that is that they car looses RPMs when I hit the accelerator and will die or almost die. If I slowly press the pedal then it will eventually rev up. It doesn't occur above 2000 rpm when I can actually get it there. I'm going to search the forum but I'm guessing it could be a vacuum problem. Thanks again!
 

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I appreciate the information. I hope that I don't have to go to that extreme but I guess I will find out at some point. The first issue before I tackle that is that they car looses RPMs when I hit the accelerator and will die or almost die. If I slowly press the pedal then it will eventually rev up. It doesn't occur above 2000 rpm when I can actually get it there. I'm going to search the forum but I'm guessing it could be a vacuum problem. Thanks again!
Because that's a ZX and the symptoms may possibly be similar to mine, I'll share this. I have an 83 ZXT and it ran like crap for two years. It would not rev above 3500 RPM without missing like crazy, and would barely accelerate above that engine speed.

On this forum, @zmanofwashington suggested that I disconnect the ECU for 15 minutes or more, then re-connect it and drive it. I disconnected the battery, then the ECU for 30 minutes, then re-connected ECU and then battery. I drove it off and it ran perfectly!

That's easy to try - pull one screw on the driver's rocker panel, one screw holding the kick panel onto the left side, and drop the trim panel under the steering wheel (two screws.) You then have access to the connectors on the eCU and can unplug all three without dismounting the ECU. I suggest disconnecting the battery first.

Try it - it's free and easy.
 

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Hello Everyone,

I just picked up this 280zx as a project to work on with my son. It needs quite a bit of work but I know with some hard work we will be able to bring this one back to life! I am new to Z's but have wanted one for years. We were able to get it running over the weekend, but it is not running well and has a pretty bad exhaust leak at the manifold. I am in South Texas, so if there is anyone is the Corpus Christi area please reach out.

Thank you,
Gary

View attachment 106924
Hey, good looking car! You’ve probably already received this information; but definitely check your gas tank for serious tank contamination, blow out the fuel lines, replace the fuel filter, replace the air filter, check your spark plugs gaps/condition, correctly check/set your timing, disconnect the negative battery cable, then disconnect the ECU and clean the terminals and then of course hook it up again, clean up all your electrical grounds (good contact), use carb cleaner and clean up your AFM and your throttle body, and that should get you going... that’s the easy stuff.
 

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Discussion Starter #6
I appreciate the info. I have done some of it but I will try resetting the ECU and clean up the AFM & throttle body.
 

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I hope your 280zx would start running smoothly very soon and you with your son will make it possible.
 

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I appreciate that. We are already having so much fun with it! I'm glad to see him interested in something that is not electronic and learning skills that he can use his entire life. Good Stuff!
 
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