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Newbie problems

Hi there...

 

I just bought a Z the other week - a 1990 SWB NA from an ad on here (in case anyone saw it) - and I'm loving it, BUT I just wanted to ask about a couple of problems it seems to have. I should perhaps warn that I'm not too good with car things, not very good at all, in fact :/ I've got a mate who can bodge most stuff, but I'm loathe to let him lose on the Z. Anyway:

 

Firstly, sometimes the speedo needle shoots off the scale and stays there for a while (sometimes several minutes). There's a separate digital speedo installed too, and that then shows '0'. The rev counter works fine, though. Sometimes there's a chime when the speedo comes back again. I've not found any pattern to when it does this (my first car was a VW Polo, and that used to do something similar, but only after sustained 80+mph runs).

 

Secondly, sometimes when starting from cold (not ALWAYS, but maybe that's just the warm weather we're having) there's a big loss of power around 2krpm - say from 1.5-2.3k, maybe. Once it hits about 2.3k, the power kicks back in and everything's fine. But up to there, putting your foot down does practically nothing, and the exhaust sounds kind of chuggy ('chuggy' is probably the wrong word, but I can't think of a better one. It's smoother than a chug, but it's still sort of on-off-on-off).

 

Thirdly, more rarely, the steering sometimes goes heavy when it's doing this loss-of-power thing. I've not noticed it before last night, but that could just be because I'm not doing much steering at the right time (I usually leave work and get stuck in traffic for 10 mins or so). But yes, last night it definitely went heavy. This was from cold again, and it was labouring as well... and then the speedo went :S

 

I figure the steering thing is probably related to the loss of power, and I wondered if that in turn might be a faulty temperature sensor thing (I told you I know nothing). If it helps, I have noticed the climate control is not terribly good at heating :/

 

Any suggestions please anyone? I'm not *too* concerned about the speedo thing, although it's annoying, and potentially fine-earning since I live on a SPECs infested road frown.gif But this big gap in power is annoying and pretty worrying.

 

Thanks for any replies smile.gif

Featured Replies

Most likey cause of most of these faults is either a bad speed sensor (on the gearbox) or bad wiring between that and the speedo or you have one of the km/h - mph conversion boxes that is going bad. That would account for the speedo, the occasional chime and the heavy steering.

Sounds like all yuor problems are speed sensor signal related wink.gif If it is an import it will have a speed convertor box on it - this will be attached behind the speedo. If you remove this I bet none of your symptoms appear again wink.gif Other than this it could be a faulty speed sensor. Is the car automatic???

 

CheerZ,

 

Andy

  • Author

Thanks for the (extremely quick) replies smile.gif

 

No, it's a manual (sorry, meant to say but forgot :/).. but yes, it's an import. And the clocks were swapped over by the last bloke for turbo ones (well, I assume they are... there is a turbo pressure gauge or s/thing on there now). They are in km/h, though - does this mean there won't be a converter box?

 

So I can just take the convertor box out? Or I have to replace it? And this could be causing the loss of power too?

 

Is the speed sensor just for autos then? Or, if not, is it going to be relatively easy to fix/replace? I'd rather do stuff myself, but lack of knowledge/confidence means that if it looks too complicated, I'll end up taking it to a garage (which worries me cos I gather alot of places aren't Z friendly).

 

Again, thanks smile.gif

 

 

[This message has been edited by baby ice dog (edited 08-08-2002).]

As this is a NA and is most definitely an import, your problem will be a crap speedo converter.

 

If you want to check, disconnect it, this will then put the clocks back to KMH. Drive the car, if the problems dont return then you know its the speedo converter.

 

If you need one email me, I can get you one.

 

Leigh

 

 

Sounds like deffo speed convertor then. Where abouts are you by the way? It may help to have someone knowledgable look over the car with you....

 

CheerZ,

 

Andy

  • Author

OK, thanks... I will check this weekend when I get time. The clock already reads in km/h (although the digital speedo doesn't) - the last owner put little marks for 30/40/50/70mph over the top. Hmm, I'm pretty confused about speedo conversions, I guess...

 

btw, what is that chime *for*, AndyP?

The chime is to tell you that you're exceeding a certain speed. As standard Jap spec cars are limited to 112mph (180km/h) and I think that the chimes goes off around 80mph.

  • Author

Ah, I see.... how cute smile.gif

 

andyduff, I'm in Nottingham, just next to the A610 to jn26, pretty much in the thick of the SPECs cameras there (as mentioned above). If anyone wants to help me out, I'd appreciate it smile.gif I want to make sure the Z is well looked after...

Hmmm, this makes me wanna change my speed sensor!

 

Few weeks ago after mine had been stood for a week or so I drove it up the road and looked down and my speedo needle was off the scale. Sitting over the +14 mark on the boost gauge. Was most impressed!

 

Not many Z's can do 190+ mph at about 2000rpm! LOL biggrin.gif

 

Also my HICAS light came on and stayed on. Stopped at Tesco, got back in after shopping and it was fine.

 

Every now and then the speedo needle starts wanging round and twitching away then settles down again.

 

P.S. Is this anything to do with fitting aftermarket alloys? Only started to do this since coming back from the bodyshop!

 

------------------

sig.gif

 

[This message has been edited by Timmy_Turbo (edited 08-08-2002).]

Tim,

Yep, sounds like you should do a speed sensor test and/or check out wiring.

 

Baby Ice Dog (Junior Husky!?!),

It would probably worth checking the temp sensor connection on the front of the engine. It is very commeon for that to cause all sorts of mysterious problems with hot/cold engines and poor running.

I hear of a guy in Nottingham, Awefull handsome fella, who is a bit of a ninja mechanic and drive one hell of a fast Z might be able to help you out.

 

He doesn't post on the forum anymore coz its full of pre school bickering, threats, name calling and tech advice from people who would be challanged in a battle of wit with a paramecium, but if you send him a mail

 

NickB@core-design.com

 

im sure he would be more than happy to take a look at your car for you and fix any issues you may have.

 

 

 

------------------

Eat it

 

Rap Boy

 

zpimp.jpg

  • Author

hehe Jr.Husky indeed wink.gif

 

Hmm, yes, I was wondering about the temp sensor, simply because I hear so much about it causing odd problems (not because I actually know anything about them). My method of testing this weekend will be to poke about, look for general dodginess, and check that I know which bit is which... not really sure how to go about "testing" anything :/

I'm relieved to be getting the general impression that all these effects are probably from the same thing and nothing to get panicky about, though smile.gif

 

In response to Timmy_Turbo, your HICAS light reminds me that I have a "Light" warning thing lit up all the time - previous owner said he reckoned it was a "turn your lights on" warning with a knackered sensor, but it stays on when the headlights are on. My thoughts were that it was a "you have a buggered bulb" warning - sure enough, one day I noticed in the reflection from the car in front that a light wasn't working. I got out and had a look, and sure enough, it wasn't lit. I spent the day looking at the "import bulbs" tech stuff, but when I got back to the car, the bulb was working again. And it's been fine since smile.gif But the warning light is still on :/

Anyway, that's not too much of a worry right now smile.gif

 

Oh, also to Timmy_Turbo: I've got what I'm pretty sure are stock alloys, if that helps at all...

 

Thx for all the help guys wink.gif

  • Author

God, it takes me so long to reply I end up ignoring the last post :/

 

Rap Boy: Thanks for the advice, I might try him if you think he wouldn't mind (don't want to impose 'n all). He sounds like a marvellous fellow smile.gif

  • Author

Well, had a quick look around last night, and have no idea what I'm looking at/for :/ One thing I did notice, though, was that there is a thick wire leading to the battery that *isn't connected* (it just has tape over the end). I followed it back and it leads to the bulkhead behind the dashboard and disappears inside... any idea what this is, or if it's important? It's covered by that black corrugated plastic sheath stuff, and it's yellow :/

Originally posted by baby ice dog:

Rap Boy: Thanks for the advice, I might try him if you think he wouldn't mind (don't want to impose 'n all). He sounds like a marvellous fellow smile.gif

 

LMFAO biggrin.gif

 

Reason why he doesn't post on this forum anymore is because the C**T word has been banned!!! ROFL biggrin.gif

 

So nobody understands what he's saying! biggrin.gif

 

wink.gif

 

Also I think I have an explanation for my HICAS light coming on...just before I drove the car before that particular incident I topped up my windscreen washer reservoir and accidentally spilt some water over the HICAS connections! Thus causing a short and illuminating the HICAS warning light on the dash.

 

Light must have stayed on until all the water had dried off the connectors whilst driving to Tesco!!! biggrin.gif

 

 

 

------------------

sig.gif

Timmy,

 

I have a message from said God, it reads.

 

Dear Timmy, You ****ing, **** Bag of Smashed ****s, Stop Talking ****ing Crap or Ill Kick you in your **** you ****. p.s Im a ****. Love ****zilla.

 

 

 

 

------------------

Eat it

 

Rap Boy

 

zpimp.jpg

baby ice dog,

Sounds to me like it's got to be the speed sensor on the gearbox.

If your gauges read in KPH then surely it doesn't have a speed convertor fitted?

 

The garage who fitted mine put it in the wrong place (near the ECU) and it caused all of the above problems. After removing it it started doing similar stuff not long after and it was a faulty speed sensor too just to make matters more confusing.

They are easy to change if you get under the gearbox and cost about £80 if I remember rightly.

 

Symptoms are:

 

Speedo goes high/drops to zero after a few minutes driving.

 

HICAS light comes on.

 

Steering goes light at speed and heavy at parking - opposite of what it should be and causes you to have to jiggle the wheel around just to stay in a straight line at speed.

 

Auto gearbox flashes error codes on the dash at startup.

 

 

Chris.

  • Author

Well, yes the clocks read in km, and the odo's are in km too, so it is very possible I don't have a convertor. That doesn't bother me *too* much, since I have an Apexi digital speedo to tell me mph.

 

I checked the temp sensor connector, and it looked fine to me - I gave the contacts a light rub with emery paper just in case, but it's made no difference.

 

As for the symptoms: well, the speedo always goes *high*, never low, and it can happen at any time throughout a journey. Sometimes it goes off the scale (at which time the Apexi reads '0'), sometimes it just blips up a bit, and sometimes it's like the calibration is off, because it sits about 10mph above the Apexi reading (usually on the motorway).

 

I've not noticed the steering going light, only heavy - it certainly always feels steady at high speed.

As for HICAS & auto box.... don't have HICAS, & it's a manual.

 

Just to clarify then: do manuals have a speed sensor too? Sorry to be dumb.. :/ If so, sounds like it's that then. Thanks for the help! smile.gif

 

I think I will contact that wonderful-sounding NickB fellow, since there are a few things I wouldn't mind advice about smile.gif

Originally posted by Rap Boy:

Timmy,

 

I have a message from said God, it reads.

 

Dear Timmy, You ****ing, **** Bag of Smashed ****s, Stop Talking ****ing Crap or Ill Kick you in your **** you ****. p.s Im a ****. Love ****zilla.

 

 

Nick can you repeat that bud? I couldn't quite get the jist of what you're trying to say! ROFL biggrin.gif

 

 

 

------------------

sig.gif

If your Apexi goes to zero then that has definately got to be the speed sensor as that is just reading the pulses it produces to calculate the speed.

The stock speedo's are always slightly out and get worse at higher speeds.

All cars have a speed sensor on the gearbox.

 

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