Whats up

 

My 300zxTT starts up pretty bad, turns over fine but misfires until properly warmed up, if i give any throttle, when i let off the revs will die down and then cut out. if i try to pull off it will usually stall, and the turbos wont kick in until properly warm. any suggestions on how to smooth this out or if its a symptom of some issue.

 

I'm also looking for seal kits for my turbos as both are leaking and causing some pretty crazy smoke, its a jap import so im assuming it has the bigger jap turbos and i haven't had much luck searching for them, if anyone knows where i can find them.

 

Thankyou.

Have you done a compression test yet?

I could be way off the mark here, but since its so easy to eliminate then I might as well suggest it.

Try disconnecting you O2 sensors, this will make the car use a fixed ECU value, a little rich, but perfectly useable.

My car has a faulty O2 sensor which was far more pronounced when cold. It misfired, lumpy and down on power. I disconnected both of the sensors and its been fine ever since.

I've since used DataScan which confirmed one of the sensors was lazy/dead, must get round to replacing them!

I am not clued up mechanically as i should be concerning cars owning a 300, so im pretty much looking for options, ideas. so no compression test yet, as i wasnt sure what/how to check. that'll go on the list to do.

Hi Maathew, basically it can be many things causing the misfire. Check all the coil and injector plugs and loom for corrosion as these commonly become green and brittle with age. It may sound stupid but this time of year with damp conditions it don't go well with 20 year old electrical components which have been made brittle with the heat these engines produce. Once the engine has got to temperature you can find the engine can run a lot smoother.

Regarding the boost, this may also be electrical related. Try cleaning the water temperature sensors, one sensor sends signal to the ECU to tell engine is at temp. Until then it will remain in safety boost.

It may something simple like a small boost/ vacuum leak. Obviously without seeing it or hearing it can be difficult to diagnose.

If you need help I only live down the road in Box, I got ECU plugin and could check all sensors and base idle etc.

 

There's a few zed owners close to you, I now of two in melksham and two in Trowbridge.

Was your 300 in Atworth garage the other week? Seen a red 300.

Whats up

 

My 300zxTT starts up pretty bad, turns over fine but misfires until properly warmed up, if i give any throttle, when i let off the revs will die down and then cut out. if i try to pull off it will usually stall, and the turbos wont kick in until properly warm. any suggestions on how to smooth this out or if its a symptom of some issue.

 

I'm also looking for seal kits for my turbos as both are leaking and causing some pretty crazy smoke, its a jap import so im assuming it has the bigger jap turbos and i haven't had much luck searching for them, if anyone knows where i can find them.

 

Thankyou.

 

Get it on a diagnostic system ASAP, it will give you all the information you need as to sensor outputs. Not wanting to sound blunt, but there's no point chasing your tail guessing when it's a 5 minute job. Jimmer @ PowerZed is fairly close to you, based in Bristol if you need assistance :)

 

Turbos are essentially the same regardless of region & transmission type. The only difference is the turbine housing is A/R 0.54 for the auto, A/R 0.63 for the manual. Seal kits are the same.

 

Don't drive it much if the turbos are leaking on the intake side, oil lowers the octane rating and can lead to detonation.

 

I could be way off the mark here, but since its so easy to eliminate then I might as well suggest it.

Try disconnecting you O2 sensors, this will make the car use a fixed ECU value, a little rich, but perfectly useable.

My car has a faulty O2 sensor which was far more pronounced when cold. It misfired, lumpy and down on power. I disconnected both of the sensors and its been fine ever since.

I've since used DataScan which confirmed one of the sensors was lazy/dead, must get round to replacing them!

 

That's odd, lambda feedback isn't operational until 25°C on a UK ECU, 50°C on a Japanese ECU. In theory, it shouldn't have made any difference at all below these temperatures.

^^^ My car isn't running a standard ECU, but some historic tuner ECU, who knows how its set up?, but during warm up it runs rough with them connected. DataScan shows one is dead, can't remember which, but disconnected there is no problem.

@Icewhitebear That was my 300 in the bear workshops, atworth, i didn't realise there were so many 300's around this area. i had only ever seen a silver z in melksham once. And It would be really great if you could plug in to my ECU sometime.

 

Regarding o2 sensors, i haven't actually seen any, there is a lot of unplugged wiring i need to go through, i think it could have possibly been an automatic convert. there is a lot of cleaning up to do.

 

Car is smoking when letting off the throttle rather than when accelerating, from what ive heard that means it isn't leaking intake side.

 

 

Thanks for the input.

@Icewhitebear That was my 300 in the bear workshops, atworth, i didn't realise there were so many 300's around this area. i had only ever seen a silver z in melksham once. And It would be really great if you could plug in to my ECU sometime.

 

Regarding o2 sensors, i haven't actually seen any, there is a lot of unplugged wiring i need to go through, i think it could have possibly been an automatic convert. there is a lot of cleaning up to do.

 

Car is smoking when letting off the throttle rather than when accelerating, from what ive heard that means it isn't leaking intake side.

 

 

Thanks for the input.

 

What colour smoke? Does it smoke when first started up? Are hot starts OK with no smoke?

Smoke is white, and smells like oil burning. It doesn't usually smoke when just started up, if its sat idling it will start to and just steadily stream out.

the worst time is when coming out of 60 roads and into town having to drive slow and then any stopping, large plumes of smoke woft out.

Definitely just the turbo seals then. Vapourised oil, straight out the back.

Hi Maathew. Agree with Noz,sounds like the turbo seals are going.

Is this your daily car or second car for weekend/ pleasure. I take it you are considering rebuilding the turbos yourself as you mention purchasing seal rebuild kit. I rebuilt mine about five years ago and without the recommended balancing, but I did meticulously check and clean everything and measure tolerances. I ve been running about 12psi for 5 years now however for the last year my passenger turbo is smoking on idle, but haven't had time to take off and get rebuilt And balanced by a professional company.

Personally I like the challenge and have learnt a lot by doing things myself over the forthteen years of ownership, however sometimes you just have to say no and get things done professionally.

Basically I think I've been lucky to go so long without failure, so I highly recommend getting them done professionally.

 

Your welcome to Pop down for a chat or I could pop over although am busy for the next few weekends trying to finish my extension before Xmas, pressure from the Wife:thumbdown

Alternatively give jimmer at powered a call as Noz suggested. Zed specialist.

@Icewhitebear That was my 300 in the bear workshops, atworth, i didn't realise there were so many 300's around this area. i had only ever seen a silver z in melksham once. And It would be really great if you could plug in to my ECU sometime.

 

Regarding o2 sensors, i haven't actually seen any, there is a lot of unplugged wiring i need to go through, i think it could have possibly been an automatic convert. there is a lot of cleaning up to do.

 

 

Car is smoking when letting off the throttle rather than when accelerating, from what ive heard that means it isn't leaking intake side.

 

 

Thanks for the input.

 

Hi Maathew. I see you got your 300 at the Bear Garage again, Been parked up outside for some time. Was just wondering if you were getting the tubs done.

Might possibly get mine out of hibernation this weekend and have a nosey if your about.

Whats up

 

My 300zxTT starts up pretty bad, turns over fine but misfires until properly warmed up, if i give any throttle, when i let off the revs will die down and then cut out. if i try to pull off it will usually stall, and the turbos wont kick in until properly warm. any suggestions on how to smooth this out or if its a symptom of some issue.

 

I'm also looking for seal kits for my turbos as both are leaking and causing some pretty crazy smoke, its a jap import so im assuming it has the bigger jap turbos and i haven't had much luck searching for them, if anyone knows where i can find them.

 

Thankyou.

 

Much has already been said as above; but my comments:

 

Bold 1 - yes; that is normal. The car is set to remain in "safety boost" until up to temperature, only when warmed up does it permit full boost.

 

Bold 2 - no; just as Noz says..... There is very, very little difference between UK and J-spec when it comes to engines, turbos etc. As ever, that is just another myth - think about it; why would manufacturers make a single car so different across the world? It would cost them £billions to homologate different versions of the same car for several different markets! The only differences in turbos is between auto and manual versions - those on the automatic cars spool up (slightly) quicker, so as to reduce any drop in performance caused by the reactions of the auto 'box....

I think the Supra MKIV was the most different between the UK & JDM models. Ceramic vs steel blade turbos, 440cc vs 550cc injectors, different cams, plus the various other differences with the bonnet scoop & better brakes etc.

I think the Supra MKIV was the most different between the UK & JDM models. Ceramic vs steel blade turbos, 440cc vs 550cc injectors, different cams, plus the various other differences with the bonnet scoop & better brakes etc.

 

I think you're right Noel - the UK spec Mk4 Soops came with 326bhp and bigger, better brakes; not to mention better equipment levels by miles....:wink:

Hi Maathew. I see you got your 300 at the Bear Garage again, Been parked up outside for some time. Was just wondering if you were getting the tubs done.

Might possibly get mine out of hibernation this weekend and have a nosey if your about.

 

New turbos are in, new spark plugs, all new belts, new o2 sensors, some new hoses, all connectors cleaned. egr delete, cruise control delete, air con delete and a few bits im probably forgetting.

 

engine bay looks a lot cleaner but first start up and run didn't go all that well, it runs and drives but not well.

the car originally had no o2 sensors at all, the crank sensor plug had a resistor in it rather than being plugged in. wondering if that has anything to do with it, but running it with diagnostics sometime this week which should make it all clear I hope.

 

*engine bay work wasn't to fix the original problem, turbos were shot so while engine was out thought id get everything I could up together.

If you still can not sort it get it over to me your not that far away,i have consult and will take a look for you.

Hi Maathew. Thought that was the case, one of my employees drives past the bear garage every day and has seen it on the ramps with engine out.

The crank sensor with the resistor you mention about is the Knock sensor which has been by-passed to stop the ecu hitting the safety mode.

Sounds like it needs a proper consult to check what's going on really. If the garage does not have this then you might struggle to diagnos problem and set up correctly.

Pop it down to Jimmers, properly your best bet.

If you want any help or advice or need to look at mine to compare anything your welcome. Only down the road.

I got some diagnostics on it and it came up with code 13, coolant temp sensor is faulty, ive read that this may tell the ecu the engine is cold when not, dump too much fuel in and bog the engine down, which is exactly how it feels because I have no power.

 

I couldn't find one in this country on ebay or zcentre etc. I was hoping someone might have a part number I can use to locate one?

 

thanks!

coolant temp sensor partnumber: 22630-51E00 or 22630-51E02

 

I would have a good look at the connector for the sensor first (and maybe replace it), most likely that's the one causing the error and not the sensor itself.

If you find you need a replacement coolant temp sensor, get it from Mike at MJP Easterm Auto, he's in the traders section. Cheaper than the dealers.