Jump to content
SAU Community

Recommended Posts

overfueling causing a rich misfire due to air leak, dodgy afm, bad spark (coils or spark plugs).

That or it is leaning out due to fuel pump.

Smoke test the intake to rule out air leaks, replace the coil packs as good maintenance on a 20 year old car, new plugs with 0.6mm gap to confirm it isn't a spark issue. Change the fuel pump as good maintenance on an unknown 20 year old car.

  • Replies 50
  • Created
  • Last Reply

Top Posters In This Topic

Does the car run like absolute shit at all revs? If it is out by 2 teeth it would be terrible to drive!

I hope that is what is the problem, I just think if that was the case that whoever did the belt would have noticed straight away.

i bought the car like that, and the previous owner just changed it in the service, problem is whoever done it didnt know what they were doing as they were a genral mechanic, not a nissan mechanic specifically...it has to be that. its getting put on the dyno tomorrow, air/fuel ratios and boost are being checked and they will find out whats going on

Must have been a pretty shit mechanic if they can't line the white mark up lol. Nothing nissan specific about doing a timing belt.

Good call with taking it to a workshop, be easier than trying to guess what is wrong with it.

Edited by Rolls

yeah well these guys do skylines day in day out so they know whats going on, and he said garunteed they will find the cause and the computer can be read by them obviously so enough stuffing around with it ill get it looked at properly haha

Took it to Toshi today and he figured it out....

He said the way the stock fuel pump works, it gets a lower voltage when at idle and low revs and then the full 12v at high revs.

The Walbro apparently didn't like this so he wired in another ground so that it gets full power all the time.

Problem seems to be gone....lets hope it stays that way.

^^ good job mate. my problem is fixed too. coil pack #6 was missfiring. and the ecu wasnt grounding properly apparently. got a blitz dump pipe fitted aswell while it was there. made 145rwkw in 3rd. not bad for a stockie

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

    • Check the injectors flow evenly, and are actually flowing what you and the ECU think they should be flowing. If it's starting up on starter fluid, you have a fuel issue. Is it possible under cranking your fuel pump is turning off?   The harness you replaced, is that the whole engine harness? Do yourself a test, and drop the old harness on and plug it into the Z32 ECU. It's possible they've wired things different. From memory S1 to S2 is different in RB25 and you may have a wrong loom
    • I haven’t pulled the injectors to watch them spray yet but they are clicking from the cas and all of the spark plugs are wet with fuel. I’ve thought the cylinders were being flooded from the beginning and was hoping fuel pressure would fix it. Tonight I am going to pull the rail and watch the injectors spray. Don’t know how to test/diagnose if the plugs are firing in correct sequence but that should be a timing thing and as far as timing goes my car still has the half moon for the cas can only install it 1 way. And my mechanical timing is 100% correct I posted photos above. Confirmed with the balancer on and off. 
    • I checked spark on all cylinders and they all visually have spark with the plug pulled and grounded, but plug 1 is the only one that fouled. This was a running swap that blew up and was rebuilt by a machine shop, put a new wiring specialties harness and did all gaskets, studs, and bolts while it was out.  compression is 135-150 across all cylinders. Aside from that from my understanding with the z32 ecu and maf the car should start regardless. The wiring for TPS and the dual 02 sensor/ dual knock sensor stuff shouldn’t actually stop the car from starting or even running well, (just slightly rich)  they just give fault codes. Car supposedly is supposed to start as long as you have z32 afm and ecu with the nistune base map and that’s info coming from a well known and trusted tuner who does a lot with SR/RB (Rsenthalpy). After more trouble shooting today where I’m at right now is that the cas is sending signal to the injectors they click while spinning the rotor, Fuel pressure is now set at 43psi, all cylinders have good compression and all of the plugs looked great (just wet with fuel) except for cylinder 1 which was very black (cylinder 1 has 150psi compression). all of the coils generate spark if pulled out and grounded out on the head. On the fuel pump car just pops into the exhaust. On starting fluid car will fire off. Hard to tell if all cylinders are firing off but definitley a couple. sounds like all of them but it’s only for 3-5 seconds hard to tell. 
    • Final update!!! Got the front bar fitted and sprayed and all sorted now. My cutouts worked great and the indicators aren’t just falling off. 😂  
    • Is this a brand new LSD? if so, have you followed any break/bed in procedure for it? Usually involves heaps of figure 8 patterns, a fluid flush.
×
×
  • Create New...