R33 Gtr Driving With Cold Engine

[tommis85]

Hi all,

I've started to have a little bit of an issue lately with the colder mornings when driving the R33 GTR. I'm not sure if it is directly related to the colder weather or if it's something else, so here goes - see if you can help me as I'm not sure haha. Could be a lot of things:

When I start her up in the mornings and also before driving home from work I make sure I let the car idle for at least minute so that it warms a little, but mainly to get oil everywhere. But, when I drive off it feels quit sluggish and surges ever so slightly if you give a little bit of throttle. Mind you, this is not enough throttle to make positive figures on the boost gauge - I never flog a cold car (a mate has described the engine wear to me first hand!)

But here's the catch guys....this is where it becomes interesting:

Every morning, at exactly the same mark on the temperature gauge (about 1 fifth up the gauge so still quite cold) you'll notice the car become normal in a split second. It drives and accelerate smoothly as though there never was a problem. I swear that the other day I even heard a very faint click at exactly the point where the car stopped it's issues. All of a sudden there's a change in acceleration - a tiny jolt and everything's back to normal.

It's hard to describe, but it feels like you give throttle but there's not much response in acceleration....feels very spongie.... I'm curious about it as it looks like it may be sensor / temperature related.

Could the cold weather make something stick? Is there something wrong with the *choke* fuel mixtures / AAC valves?

Please note that when the engine is warm to hot (above the 1 fifth mark I mentioned) it doesn't have any of these issues. Also, the car is completely stock with stock ECU.

Thanks for your help!

Tom

PS - temperature when this happens is around 5 to 10 degrees in the morning, and around 15 to 20 degrees in the afternoon around 5pm when I head home. Hope this helps...

[MikeyGTRmike]

My GTR does the same thing. I reckon its all due to engine temps and fluid temps.

*never heard it click though*

[DAN00H]

I think it might have something to do with the TPS. or even the timing.

[tommis85]

Mike, I see. Well, I've only heard the click once so far. I'm convinced that it's the cold weather causing something to stick. A switch, a solenoid....a sensor....something somewhere is being affected my the cold and as soon as it reaches a certain temperature it is fixed.

You know when you're leaning over the engine and you slightly open up the throttle with your hand, right? You hear a little click that I think comes from the crank angle sensor...and then rev's build up. I swear I heard that click the other morning.

By the way, I'm not 100% sure if it's the crank angle sensor that makes the click...it comes from the general area though.

Dan, if it has to do with the timing or the TPS....how would the cold temp of the engine influence this? Does timing change when the engine is cold? The thottle is not adjusted for cold start is it?....it's only the additional valves under intake plenum that let more air in to build cold start rpm's????

[tommis85]

Mike, does your GTR change back to normal at exactly the same temp as mine? Mine is about 1/5 on the temp gauge....so, about 2mm above the lowest line on the temp gauge etc

[tariix]

Mike, does your GTR change back to normal at exactly the same temp as mine? Mine is about 1/5 on the temp gauge....so, about 2mm above the lowest line on the temp gauge etc

mate mine does the same thing i think i was told that it has got something to do with a cold start tune, which is normal so i have been told to avoid flogging its mum when cold and temps reach normal driving temps

[tommis85]

Ah OK well that's all good then. Just making sure nothing is wrong with it - obviously it kicks in when it reaches certain temps when winter comes on like now.

Yeh it's like clockwork...it always goes back to normal at exactly the same point on the gauge so it must be exactly what you're saying it is.

Thanks for the help guys!

Tom

[(B1) MR_fanny]

mines the same...though its not a gtr. i also assumed it was cold start tune.

[tommis85]

Thanks Mr Fanny. Yep...them japs must have harsh winters! Hell, some of them come over with snow tires!

[paulR32gtr]

Yeah same here with my 32 gtr - hits a certain water temp, timing map changes and the car feels normal, wait for the engine oil to get 70deg and lift off.

[DLOOOK]

ditto

[tommis85]

Ok, thanks heaps guys! That's exactly the answer I was hoping for - that all of you have the same thing! Nothing to worry about then ;-)

[steven22]

Its the water temerature sensor. The one with only one plug and its closest to the head. Mine did the exact same thing. Try cleaning the connections to the one you already have and you will notice a change. The best thing to do is to replace it. If you do make sure you get the genuine one from Nissan as the ones from Bursons dont work.

Changing the sensor fixes this problem instantly.

[tommis85]

Steven, ok sweet...I will go and inspect the sensor connectors and see how it goes when I start it up. I never thought of doing that - but then, I never had that problem either ;-)

Because surely, Nissan wouldn't put such a strange tune on the car lol that feels so strange to drive ;-)

[tommis85]

Ok Steve, I went out and cleaned it just then...it had traces of green/blue oxidation on it so I cleaned it all off with RP7 (for want of a better contact cleaner haha - I should get one of them and then inspect all electrical connections!)

See how she goes a bit later

[just32gtr]

Ok Steve, I went out and cleaned it just then...it had traces of green/blue oxidation on it so I cleaned it all off with RP7 (for want of a better contact cleaner haha - I should get one of them and then inspect all electrical connections!)

See how she goes a bit later

hi my gtr does the same until like it just gets warm. Where abouts on the head is the water temp sensor?

[tommis85]

At the top of the block on the left side (when standing infront) and it's the ones with the single lead. It is also closest to the block and it's hidden behind a larger sensor.

It is also hidden under the black hose the encases the injector leads.

[tommis85]

Our GTR's came from a crap, wet and cold climate from Japan so it'd be a good idea to do all the electrical component connections and bolted earthing connections. I noticed that they all could do with a clean so that's what I'll do guys. Let ya know how it goes I guess ;-)

[ferni]

It's normal for a GTR. My GTR did the same thing on the standard ECU. It's the Closed Loop/Open Loop thing, protecting the engine.

When you change the ecu it doesn't happen anymore. But it's not a bad thing anyway.

[tommis85]

Ferni...now that's what I was suspicious about but didnt have the balls to ask about.

The RB26 is such a great engine....why wouldn't they have installed a system that stopped utter noobs from powering out of their driveways on a cold engine??? Well that's all good then bro....I was just wondering as my GTST never did that ;-)