Buying a Nissan 300zx that has been sitting for 5 yrs, Runs Rough. Help? (VID)
#11
07-04-2011, 09:49 PM
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#12
07-04-2011, 11:57 PM
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Hate to say it but considering it's a 1990 model I'd prolly pass on it. The heads were all jacked up on those, at least try to find out if they were replaced. Here's a snippet I found when when trying to remember what the issue was with the 90 a friend had. (I've owned both 280 and 300zx's during my misspent youth but a buddy was the one with a 1990, it was a pita).
"The driver's side head was machined wrong and the result is a problem with the crank angle sensor to exhaust cam splined joint. They will wear themselves out and the car will develop a hesitation that will continue to get worse. There are some Band-Aid fixes like only replacing the CAS ($350) or the cam and sensor ($2100) but the real fix is to replace the heads. Check with the dealer about a TSB Nissan has issued on this problem to see if your car is affected. I believe all 90 models are".
Apart from that there's a host of other things you can do to help it along, here's a link to the page that snippet came from. It's full of tips to fix poorly running 300zx's.
TwinTurbo.NET: Nissan 300ZX forum
"The driver's side head was machined wrong and the result is a problem with the crank angle sensor to exhaust cam splined joint. They will wear themselves out and the car will develop a hesitation that will continue to get worse. There are some Band-Aid fixes like only replacing the CAS ($350) or the cam and sensor ($2100) but the real fix is to replace the heads. Check with the dealer about a TSB Nissan has issued on this problem to see if your car is affected. I believe all 90 models are".
Apart from that there's a host of other things you can do to help it along, here's a link to the page that snippet came from. It's full of tips to fix poorly running 300zx's.
TwinTurbo.NET: Nissan 300ZX forum
#13
07-05-2011, 06:19 PM
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Stock motors for the 300 have a weak bottom end, try to find the motor code if you can. I cant remember what the stock one is I think its like V(something)32 but I know alot of people do the JDM vg30dett motor swap and It makes a wonderful car. but never the less those car are going up in value as we speak. Higher gas prices will make them go up even more. I think 2500 for it and it even starts sounds like a good deal.
correct me if I am wrong on the codes. Its been about 7 or 8 years since I've worked on a 300zx
correct me if I am wrong on the codes. Its been about 7 or 8 years since I've worked on a 300zx
#14
07-09-2011, 05:36 PM
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some misinformation here about the bottom ends. the car is a z32 the engines are all vg30de or vg30dett, all are identical jdm or usdm, only vary based on de or dett, and valve changes after a couple of years
the vg30 is a really really strong engine, I state this with ALOT of first hand experience considering I own one and after leaving nissan as a technician i spent the last 3 years working on 300zxs specifically. The engines are super super strong. there are guys running over 600whp on stock vg30s for multiple seasons.
over 400 and 500 hp is easy for it. over 400whp is reachable without touching turbos. the life of the turbos as mentioned is true and false. the thing that will happen is they'll blow seals and smoke like crazy but they'll still boost no problem. I was personally running my stock turbos at 20psi when I had them and I went with 20w50 engine oil to reduce smoke from the tailpipe since people then think its broken, but it was tonns of fun.
the early year 90 like mine did have soft valves, I had to remove my heads to replace valves a couple of seasons ago due to low compression in 1 cylinder from pounded valves.
as for wires it wont be necessary, they run coil packs.
the only common issues with 300zxs are the ignitors on the early style 90-93 or 92 cant remember exactly which year they changed them, the 90-93 pintle type injectors will die out of nowhere which can be a pain in the ***, the 90-94 hicas 4 wheel steering usually leaks in the rear, but that was my favorite delete i ever did, the car is much safer and more predictable without it.
and i wouldnt ever ask a question on twinturbo.net alot of elitist ******** there who will just tell you search in the rudest way. go to 300zxclub.com.
I've owned alot of different cars and the 300zx is by far the best and my favorite.
my baby...
oh and an injector job your first time might take you 4 or 5 hours to pull apart, then you'll do the coolant bypass mods to delete the lines which makes it easier and if you ever delete egr then the plenum pull is 10-15 mins.
i went to the newer 550cc injectors but then switched out to 850cc saards
the vg30 is a really really strong engine, I state this with ALOT of first hand experience considering I own one and after leaving nissan as a technician i spent the last 3 years working on 300zxs specifically. The engines are super super strong. there are guys running over 600whp on stock vg30s for multiple seasons.
over 400 and 500 hp is easy for it. over 400whp is reachable without touching turbos. the life of the turbos as mentioned is true and false. the thing that will happen is they'll blow seals and smoke like crazy but they'll still boost no problem. I was personally running my stock turbos at 20psi when I had them and I went with 20w50 engine oil to reduce smoke from the tailpipe since people then think its broken, but it was tonns of fun.
the early year 90 like mine did have soft valves, I had to remove my heads to replace valves a couple of seasons ago due to low compression in 1 cylinder from pounded valves.
as for wires it wont be necessary, they run coil packs.
the only common issues with 300zxs are the ignitors on the early style 90-93 or 92 cant remember exactly which year they changed them, the 90-93 pintle type injectors will die out of nowhere which can be a pain in the ***, the 90-94 hicas 4 wheel steering usually leaks in the rear, but that was my favorite delete i ever did, the car is much safer and more predictable without it.
and i wouldnt ever ask a question on twinturbo.net alot of elitist ******** there who will just tell you search in the rudest way. go to 300zxclub.com.
I've owned alot of different cars and the 300zx is by far the best and my favorite.
my baby...
oh and an injector job your first time might take you 4 or 5 hours to pull apart, then you'll do the coolant bypass mods to delete the lines which makes it easier and if you ever delete egr then the plenum pull is 10-15 mins.
i went to the newer 550cc injectors but then switched out to 850cc saards
Last edited by 99specz32; 07-09-2011 at 05:39 PM.
#15
07-09-2011, 05:42 PM
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but yeah as for running rough, its usually either the ptu which is the ignitor
failed injectors, pull the connectors off them and test resistance should be 10-14ohms iirc (i switched to a honda dealer in november lol)
or another option the engine harnesses on them get cooked and become brittle and cause issues over time, anytime the engine is pulled out usually for upgrades you automatically replace the efi harness and engine mounts it's cheap anyways.
failed injectors, pull the connectors off them and test resistance should be 10-14ohms iirc (i switched to a honda dealer in november lol)
or another option the engine harnesses on them get cooked and become brittle and cause issues over time, anytime the engine is pulled out usually for upgrades you automatically replace the efi harness and engine mounts it's cheap anyways.
#16
07-09-2011, 06:27 PM
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