Jump to content
SAU Community

Recommended Posts

R34 Neo Turbo

Car wont start now unless I give it a small bit of 'Start ya Bastard' then it fires 1st go and idles fine.

It has been taking longer and longer to start over the last month and today it wouldnt start at all without some help. Car was having this problem before, but I have just changed, turbo, injectors, ECU, coilpacks x2.

I do get code 21, ignition, but that was when I had a missfire. I changed coilpacks and it now runs fine when started. I haven't rechecked to see if Im still getting code 21.

Link to comment
https://www.sau.com.au/forums/topic/425625-r34-hard-to-startnot-starting/
Share on other sites

Have you checked to see if you have any new codes? Link to codes

Just on the issue of hard starting

- Plugs fouled or incorrect gap

- Battery - Cranking power (no dead cells)

When you were changing the turbo, injectors and coilpacks - did you move/unplug the TPS, TCS etcetera ... have you reset the ECU since then and checked for new codes.

Maybe the quickest way to identify your issue/s.

So bit of an update,

Changed spark plugs, no change.

Showing Code 55 (no faults)

I can restart the car if I have had it running within 30 seconds otherwise I have to give it another spray of start ya bastard.

Im starting to thing vacuum leak. I say this because if I give it a rev it drops to 500rpm after and then goes back to idle at 1000rpm. It doesnt catch the revs on the way back down, if that makes any sense.

I had this once, after doing pretty much everything in this thread, and it turns out that it was caused by the ECU not giving any timing when starting the car.. even though once started it would run fine...

I had this once, after doing pretty much everything in this thread, and it turns out that it was caused by the ECU not giving any timing when starting the car.. even though once started it would run fine...

Ive got a spare ECU ill change it and try again but I have just replaced the ECU. Had the problem before and after. Ill give the CAS a swap and AFM and after that im offically out of ideas.

My ECU was fixed by the tuner who was like "uh oops" but there were plenty other issues at the time. ECU has since been changed and this was quite some time ago. I do recall the problem quite annoying at the time!

In my case it was a piggyback ECU sitting ontop of a normal ECU. You didnt mention what ECU you changed but I'd imagine no stock ecu would ever have a problem like this..

Checked all vac lines? Even under the charcoal canister, sometimes the vac hose coming out the bottom comes off. I had this happen on my 34. You can't see that its come off unless you specifically feel the underside of the canister.

Edited by RB25DETC33
  • 2 weeks later...

So problem solved thanks to Jaustech.

The ECU gets start signal, and it has an inline fuse. The fuse had gone. Im not sure what the ECU does when it gets a start signal, possibly a bit more fuel to help kick it over im not sure.

To diagnose this you need to print off an ECU pinout diagram, find the 1 relating to starting and check to see if its getting a signal when cracking.

Now im not sure if the fuse is away from the normal fuse panels (drivers side engine bay/Drivers foot well) or not, but apparently that was the issue and it start like a dream now and runs great.

Moral of the story, check your fuses and if they are all good. Get the pinout for the ECU, find 1 relating to start signal, test.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Guys since i bought r33 gts25t coupe 1994 automatic a/t(manual swap 350z gearbox)  all i got is problems, always problems. Lets start with that when i turn key into ignition(ON) fuel pump doesnt always works. Sometimes i have to turn key twice Off/on/off/on until it primes. Its new, dw300 - 340lph. My gearbox broke so i did gearbox swap, install different intake manifold, injectors and i take pipes. Car was sitting in garage for more than half a year. I did assembly all not that long ago and when i turn ignition cant hear prime. All of sudden it stopped working. Theres many videos on YouTube how to make relay mod on r33 straight from battery so i did and it doesnt work! 😰 30 - battery positive  87 - positive from fuel pump to relay 85, 86 - one of two wires from original fuel pump wires(light blue, grey) and it didn’t work. so I check on ignition and took original BLUE relays wires from trunk, next to fuses. (I believe it’s IGN+ and ECU pin 18. it didn’t work…  tried connecting (IGN+ from og relay) and (ECU 104 from 1of4 FPCM wires) to my new relay 85/86 and it didn’t work.  I unplug FPCM. Didn’t work. im thinking what’s wrong   fuel pump is working, if I leave IGN+ on 85 and 86 straight to ground it works but it’s just nonstop. Since it getting constant 12v after key in ON. light blue wire gives me 6-8v.  so how this should be connected? What causing ECU not giving — on pin? Or I did sth wrong and that’s why it doesn’t work? I need negative signal on ECU that control fuel pump. What this should be?
    • You can use your VIN to look up the factory part number somewhere like amayama, and then look to order new if necessary. https://www.amayama.com/en/genuine-catalogs/nissan Depending on price you might want to rebuild instead. @GTSBoy I had an interesting insight into US market parts when the Titan rear calipers were sticking. New calipers were dirt cheap, about 20% more than a rebuild kit....they are just considered throw away maintenance items
    • Funny, but really not funny. Thank god (most) f the world has moved on since then
    • Lots of votes for driving onto a plank first; that is the quickest way I've found, 25mm is enough for my case but that will vary by car It also depends where you are going for. On the 32 I can get to the rear diff with my floor jack if I do that end first, and get it up on stands. Then I lift the front from either front tow hook as high as needed, also onto stands. Sometimes I need a small lift on the other tow hook to get it level enough If I do the front first I can't get to the rear diff because of the angle of the car Other options are getting to the front mount of the rear subframe from in front of the wheel (if only lifting one side, or just do both which is a bit of a pain compared to one lift from the diff), or also the gearbox cross member mount on the driver's side if you are  just trying to lift the driver's side. I This is the jack I use; it says 75mm clearance but of course that is only on the lower section so if you have to reach too far in like the diff you still get stuck. https://www.snapon-bluepoint.com.sg/category/Floor-Jacks/product/Floor-Jack,-2-Ton-Low-Profile
    • On the bright side, the weather will turn much nicer for working outside shortly....sounds like you might need to start on a neighbour's garden next
×
×
  • Create New...