Jump to content
SAU Community

Gtr 32 Not Making Boost - Further Suggestions?

dorifticon

By dorifticon,
in General Maintenance

 Share

Recommended Posts

dorifticon Community Regular

dorifticon

Posted
Posted

Well, I imported an GTR32 and as is usual with imports, it was running pretty rough when it came off the boat. So anyhow, tracked down and fixed a couple of boost leaks and associated issues, and it now is idling cleanly and starting sweetly, but not making any boost.

Now, a couple of people have posted up similar problems, but they seem to associated with misfiring and/or various colours of exhaust smoke, which is not consistent with my experience. Also a lot of the other posts seem to be correlated with ‘catastrophic events’ or other sudden failure, whereas mine has just kind of always been shite.

Basically, it is running like a 2.6 n/a with a low static compression ratio (not very impressive). It revs out and doesn’t hesitate, just doesn’t make any boost. It doesn’t blow any kind of smoke (either black or white/blue) and doesn’t seem to consume oil.

So far I have:

1) run an air/fuel meter, which returned 14:1 (pretty much where I’d want it, yeah?)

2) checked the timing – was advanced to about 25 deg, so reset it back to 15 deg BTDC (i.e. what it says on the bonnet)

3) disassembled the intake (passenger) side of the motor – a couple of the rubber hoses to the wastegates were looking a bit worse for wear, so I replaced them with high-pressure efi hose and clamped ‘em down real good. I also took the opportunity to really tighten off all associated hose clamps, as well as replacing the very large rubber pipe that comes off the collector (the one that connects to the pipe that is stamped “twin turbo” – my one had a minor split).

4) examined turbos – the compressor wheel didn’t seem to have any excessive shaft play or damage, but then I’m no expert. I haven’t had a look at the exhaust wheels yet, haven’t removed the dumps – that may be the next thing. The wastegates seemed to have a ‘normal’-ish kind of resistance to them, and everything seemed to spin reasonably well. Nothing jumped out as being seriously wrong.

5) examined plugs – all sparkplugs looked fairly clean, very little carbon or any kind of damage there. But then it wasn’t misfiring at all so that makes sense.

6) here is the wild card – when I got the car, something called the ‘PCM valve’ (small valve kind of behind the battery area) was unplugged. Now, the actual plug was ziptied out of the way, so it doesn’t look like this was accidental. Anyway, I just plugged it back in. Having searched, it seems the PCM has something to do with the EGR system, but that’s all I know.

Anyway, the next thing I’m going to try is looking at the cat converter to see if it’s somehow collapsed or something equally ridiculous.

If there is some vacuum related issue on the D/S I would probably prefer to yank the motor rather than attempt to remove the inlet plenum with the motor in the car (search has told me the inlet is a PITA to remove in the car). I have the engine crane and other tools, and the will, to remove the motor if required (although have not done engine removal on a 4wd setup like the r32).

At this stage I’m really just looking for clues or suggestions on where to go. In particular

1) what is the PCM valve, what does it do and why would someone unplug it? Is this the solenoid people modify to increase boost to 1 bar, and if so wouldn’t plugging it back in simply return the car to factory boost (as opposed to zero boost)?

2) can the car have a boost leak and still idle cleanly and maintain normalish AFR’s even under various load/RPM conditions?

GTRsean Grand Master

GTRsean

Posted
Posted

Ceramic turbines are well known to fail and then you get next to no boost.

See if there is any ceramic turbine remains in the exhaust before the cat converter.

Soleniod behind battery is the stock boost control solenoid.

dave32gtr Contributor

dave32gtr

Posted
Posted

This wont help at all but. I did have my car stop making boost for anout 5 min once. Don't know what happened. Then it just cam back befor i got to where I was going. That was about 5 years ago, and it has never done it again.

dorifticon Community Regular

dorifticon

Posted
  • Author
Posted
Ceramic turbines are well known to fail and then you get next to no boost.

See if there is any ceramic turbine remains in the exhaust before the cat converter.

Soleniod behind battery is the stock boost control solenoid.

GTRsean = teh winnar!

I was also kind of right, the cat converter was blocked - with this (see pic)

Oh well, just means its HKS ball bearings for me (stand by for dumb questions about turbo upgrades)

post-45795-1219461818_thumb.jpg

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • MBS206
      Dose's Sometimes DIY and Pay Someone Home & Boat Improvement Thread

      By MBS206 · Posted

      Why are people so insistent on making dirty water?!
    • Dose Pipe Sutututu
      Duncan's V37.......race car?

      By Dose Pipe Sutututu · Posted

      Fark what are the changes of that snapping like that, clean. Nek minnit, custom radiator goes in, with built in oil cooler like those discontinued PWR ones from yesterdeacades ago
    • Duncan
      7 Speed Auto transmission fluid change (Skyline, Q50, Q60, Fuga, Q70, A62 Titan and probably heaps of others including Navara...)

      By Duncan · Posted

      I thought I'd do a write up on an auto transmission fluid change for a the nissan 7 speed Automatic. At some stage the genius engineers decided that the fluid in the trans was "for the life of the transmission", (which seems kind of self supporting to me) and removed the dip stick and fill tube (funnily enough there is still a casting for it). Anyway, for this job you do need 2 specialist tools in addition to regular hand tools, jack and good chassis stands. You need a way to pump fluid up to the transmission; I got one of these but there are plenty of other options: https://www.ebay.com.au/itm/364584087070 Don't trust the generic listing though, it does not come with the required adapter for the Nissan 7 Speed. You need one of these, can't do the job without it: https://navarapart.com.au/product/genuine-nissan-patrol-y62-d23-np300-navara-re7-dipstick-fill-connector1 You need a heap of compatible transmission oil. Could be Nissan, could be anything else rated for Nissan Matic S. You need at least 10 litres, I had 15 to give it a better flush... Also, you need some biiig oil catch trays, at least one of these, or bigger if possible (volume was fine, size was very marginal): https://autobarn.com.au/ab/Autobarn-Category/Tools-%26-Garage/Specialty-Tools/Oil-Service/Garage-Tough-Oil-Drain-Pan-Black-16L---GT1068/p/TO03191 Finally, a measuring jug is very useful if your pump does not have volumes marked on it, I got a 6l one: https://www.repco.com.au/oils-fluids/fluid-accessories/measuring-jugs/penrite-measuring-jug-6l-pmj006/p/A5322648 Oh, and gloves.....this stuff is horrible (not as bad as diff oil, but getting there) ....First, jack up your car.....
    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      So I mentioned the apprentice, @LachyK helped take the bonnet off. We just undid the nuts on the hinges and unclipped the gas struts, then pulled the bonnet back a little as the front was catching on the front bar.  I had a good look at everything today and have removed the rams, repaired/reset the hinges and bolted it back together like it never happened. I'll do a separate write up on the repair, and I also removed the poppers from the Fuga today too to save grief down the road.....as said above it is at least $5k to repair retail. I'm also happier about my ability to prepare a race car, and less happy about Nis-nault's engineering (I can hear @GTSBoy sAfrican Americaning) because the top hose of the radiator didn't slip off.......it snapped clean off. By practice I put the hose clamp hard up against the flare on a neck to make it least likely to ever move (thanks @Neil!). I guess that puts a little more pressure on the end of the pipe as it is further away from the rad, but still, that is pretty shit. I've put it back on for now as there was a fair bit of neck still there, but obviously there is no lip on the neck any more so I don't think I'll track it again until I have a new rad. Speaking of which....more research required. It looks like Koyo makes a standard size radiator in ally which I'll grab in the meantime, but I really want something thicker so might have to go custom in the medium term (ouch) Coolant still needs a refill and I have the pressure tester on it over night, but other than a wash down of the engine bay it seems alright. And @MBS206 noted something noisy on the front of the engine and I think I agree....time for a new accessory belt and tensioners I think.
    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      our good friends at nismo make a diff for it, I have one (and a spare housing to put the centre in) on the way. https://www.nismo.co.jp/products/web_catalogue/lsd/mechanical_lsd_v37.html AMS also make a helical one, but I prefer mechanical for track use in 2wd (I do run a quaife in the front, but not rear of the R32)
×
×
  • Create New...