New owner! Massive problems..

[ShaneZ32]

Hey all! I just picked up my first Z yesterday and Love it! However.. she doesn't run anywhere near right.

Checked ecu Diagnostics, LED doesn't come on at acc position even after turning the screw.

Issues are that it runs super rich, and idles really low (around 200 rpm). When I bought the car yesterday it had a bad miss. I replaced the plugs and it fixed it. I have checked for vacuum leaks and checked the MAF. The injectors are all reading correct ohms. Possible bad computer?

Car has 81k miles, but has sat for a good number of years.

Next question, do I need to buy different motor mounts to swap from NA/auto to TT/manual? I'll have a new computer and harness all sensors and everything. I just figured since the trans in it is going and all the issues that could be possible it's be easier and possibly cheaper to just swap out, plus I wanted to boost and go 5 speed anyway.

Thoughts, Opinions? Thank you!

[KillaZNA]

Before you go and spend all your hard earned dough on a new computer. Make sure all the connectors are clean. They love to corrode and get loose. Make sure all connectors are tight and not flopping around. Try and adjust the idle by raising it. It should idle at around 800-900rpm for automatic.

If it runs smooth over a certain RPM I.e over 2k or 2.5k then it could be either a bad TPS, PTU, CAS. Let me know what you find out.

[ShaneZ32]

I've checked all connectors under the hood and at the computer. I seriously can't come up with the reason it runs so terribly. I also has extremely limited power. I've just about made up my mind on doing the 5 speed TT swap. I just need to know if the motor mounts are the same.

[KillaZNA]

It's the same motor mounts. It's worth checking the injectors.

[DCaff300ZX]

If the car has sat as you say for a very long time, you are definitely going to have some corrosion issues with a bunch of important electrical connectors that can cause the problems you mentioned.
The PTU harness is a great place to start by checking each connector for the green corrosion, as well as the injector connectors which surely will be green. The CAS connector can also get bad, as well as many of the connectors in the back of the engine at the IACV.
Another good thing to check given sitting is if the PCV hoses are intact and PCV's working, as well as the vacuum hoses around the booster that get hard and can cause vacuum idle issues.
These cars don't do well sitting in the weather for long periods of time, you will need to do a thorough cleaning and inspection of the things mentioned here and more depending upon the condition of the car.

[ShaneZ32]

Thank you all for your responses. I have decided just to swap to TT with auto trans. I found a killer deal locally! If you all would like and it would benefit the forum I can do a full, detailed writeup!

[KillaZNA]

Why not do a manual trans as well or is money the issue? You can find a rebuilt trans for about 5 to 6 hundred and the ecu will run about 2 or 3 hundred. You also need the harness. It's just not as fun with only 2 pedals. Where do you live I'll buy your old motor from you.

[ShaneZ32]

I live in kingsport, Tn. I'm between getting the clip with manual trans or getting auto swap package. Money being the issue. But I think it'd be cheaper to get the clip. How much would you give for the motor trans and computer?

[300ZXttZMAN]

If the car has sat as you say for a very long time, you are definitely going to have some corrosion issues with a bunch of important electrical connectors that can cause the problems you mentioned.
The PTU harness is a great place to start by checking each connector for the green corrosion, as well as the injector connectors which surely will be green. The CAS connector can also get bad, as well as many of the connectors in the back of the engine at the IACV.
Another good thing to check given sitting is if the PCV hoses are intact and PCV's working, as well as the vacuum hoses around the booster that get hard and can cause vacuum idle issues.
These cars don't do well sitting in the weather for long periods of time, you will need to do a thorough cleaning and inspection of the things mentioned here and more depending upon the condition of the car.

To add to what Dave said - Being that the car sat for a very long time it is extremely possible it didn't have the PTU recall done. Is your PTU aluminum or plastic? (it can be found on the RH timing cover)

Oh and welcome to NICO!

[nissanfreak12]

Hey all! I just picked up my first Z yesterday and Love it! However.. she doesn't run anywhere near right.

Checked ecu Diagnostics, LED doesn't come on at acc position even after turning the screw.

Issues are that it runs super rich, and idles really low (around 200 rpm). When I bought the car yesterday it had a bad miss. I replaced the plugs and it fixed it. I have checked for vacuum leaks and checked the MAF. The injectors are all reading correct ohms. Possible bad computer?

First off, the key needs to be in the on position, but car not running. Acc position does absolutely nothing.

Still could be a possibility on the ECU, but also could mean the injectors are just gunked up from sitting for so long, bad gas, bad filter, bad fuel filter, etc.. Have you done any maintenance on the car?

Im not telling you not to do the swap, but they get expensive fast. Like I stated in another post, it cost me 5k with parts and labor, and I found a hell of a deal on a conversion with a 5 speed swap. Most guys can spend near 10k. Just make sure you do your homework on the front clip, whether its JDM or USDM, so many horror stories on JDM ones.

[KillaZNA]

I would get it if you were local but you're kinda far away. Good Luck with your Z. Don't give up on it.

[DCaff300ZX]

If you have trouble diagnosing issues with your engine which is not easy and is time-consuming to be sure, then I fail to see how the decision is to do a full TT swap with all of the trouble and cost involved, not to mention the trouble to get it working is the better option.

[nissanfreak12]

If you have trouble diagnosing issues with your engine which is not easy and is time-consuming to be sure, then I fail to see how the decision is to do a full TT swap with all of the trouble and cost involved, not to mention the trouble to get it working is the better option.

And this........

[300ZXttZMAN]

If you have trouble diagnosing issues with your engine which is not easy and is time-consuming to be sure, then I fail to see how the decision is to do a full TT swap with all of the trouble and cost involved, not to mention the trouble to get it working is the better option.

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