New member with a PTU problem

kalten · Post by **kalten** » Thu Oct 28, 2010 6:29 pm

Hi everyone

To introduce myself, we have owned a 300ZX NA 2+2 (1990 I think) for over a year and have been thoroughly enjoying it. Everything was going sweet, had some respraying done on the front end and replaced the battery about a month ago and then one day it just wouldn't start.

Our mechanic said that the PTU had failed and it was from a breaker which means it had failed before also. The garage said it would cost $900-1500 to replace but they couldn't source the part. I took the car home. After looking online I found this is a pretty common problem and the answer is to get a S2 PTU or one from a R32/33 Skyline and do some soldering.

My question is, what's the best solution here without spending a fortune and what do I need to buy if I take the skyline PTU route. I noticed on TradeMe there are some for sale but do I need to get anything extra to fit it.

Well, any help here would be good.

Cheers

BRONZEE · Post by **BRONZEE** » Fri Oct 29, 2010 7:46 am

Welcome to the forum Kalten. One of the the 300 crew will be along to help.

nzniggles · Post by **nzniggles** » Sat Oct 30, 2010 8:30 am

Here's a PM I got sent by one of the guys when I was looking at it.

Hi any PTU from a R32 skyline, for this you will have to unwrap wiring harness up to the corner of the engine, split off the PTU wiring and wrap it back up with tape

you will have to make up a bracket to bolt onto the bumper support under the light panel and have the PTU facing downwards. I have mine secured with cable ties which works fine, or try some bolts

for the wiring, the wires connect wire for wire its just the plugs that are different

line up the plugs with the groves, (yes they don't fit) peel back the rubber form the plug and label the wires with some yellow tape and a vivid 1 to 7-8 also label the skyline PTU

now all you have to do is connect the numbers with the skyline plug or just solder to the pins

ZILVER · Post by **ZILVER** » Sat Oct 30, 2010 8:56 am

The first edition/early PTU are prone to failure. Noteably so that overseas Nissan dealers recalled them and replaced them with what I'll refer to as a PTU2 - which is a complete redesign.

If you dont want to risk the 2nd hand route. You could look at importing a new one with adapter harness:
http://www.conceptzperformance.com/Cart ... IS300&UID=

Or refer to my PM regarding a known fellow club member that may have a spare PTU2 on hand/willing to sale on.

& if you are attending a club event like Nizfest - Holla at me (Or look out for the ZILVER Personalised Plate) and I can show you the relocation of a PTU2 on my ZED. Effectively hiding it under the nose panel/away from the original location which gets somewhat hot.

Pilot.P · Post by **Pilot.P** » Mon Nov 01, 2010 11:34 pm

I have a spare S1 PTU lying around (condition unknown). If you pay for postage you're welcome to see if it fixes your Z. When you say it wouldn't start can you hear the starter going? If there is no noise it may be your starter not PTU.

Yes it is not uncommon for the S1 PTU to fail, they can also slowly/randomly/progressively fail which is a nuisance. As mentioned the problem was in fact an official Nissan recall item back in the 90s. If budget allows, the S2 PTU kit can be purchased new from CZP (the link Zilver provided), this comes with the subharness which means its plug and play with no soldering work. You can get one landed for under $400, nowhere near $900-$1500!

kalten · Post by **kalten** » Wed Nov 10, 2010 6:30 pm

Thanks for all the help. ZILVER gave me a contact who sold me a S2 PTU which I have just received. I'm about to start fitting it, although I'm not sure where.

My car has the original airbox fitted so there's not much space under the center panel. Any suggestions would be great, I still have some soldering to do.

Cheers
Gav

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I only posted a week ago and my account was deleted already. What do I do to stop that happening?

ZILVER · Post by **ZILVER** » Thu Nov 11, 2010 8:33 am

Cool, solder away. I can give you a series 2 PTU mounting bracket so you can install it on the timing cover/original location.
Or it may be best to ditch the stock filter box/and invest in a decent Pod filter.

kalten · Post by **kalten** » Fri Nov 12, 2010 12:17 am

Zilver, that would be great if you would send me the S2 bracket. Tonight I finished the soldering and wrapped with fresh tape, keeping the original plastic tubing to protect the wires a bit more. I'll try starting up tomorrow once my battery has charged. I still couldn't figure out where I can fit the unit other than in the original position, which isn't possible without a bracket or spacer.

I may well change to a pod filter at some point but the air box is working fine and it looks like K&N filters are fitted. The engine is otherwise standard as far as I know.

Pilot.P, I'm fairly sure it's the PTU, the engine turned over no problem, it just didn't fire up. Eventually, it did start but died again half way down the road. The garage that looked at it got the consult error codes and tracked it to the PTU.