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my car has seemed to developed a running problem. its not all the time though and mostly occurs when its wet or been raining (which is pretty much everyday recently). i thought it may have been the plugs so got them replaced with upgraded iridium ones. hasn't made a difference though. it only happens at low revs, but once i give it a bit of throttle it clears up. its starting to really annoy me now. so any ideas of what it could be and how to fix would greatly be received! by the way the car is a 90 na import.

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i had a rough running problem at low revs and idle and cured it by pulling the iridium plugs out and putting stock plugs in! (a lot of folks will tell you iridium ones are better, but can only speak from my own experience).It cured it straightaway, as the iridium plugs are around 2.5mm shorter than the standard zed plug.I was advised to change the iridium ones on the advice of a number of people including Jeff and Jamie at Zedworld.

 

i have also noticed a big improvement at idle since replacing the pcv valves and all 5 pcv hoses with brand new ones.As daft as it may sound the engine is also quieter to the point where the difference is quite noticeable.

 

 

2012-04-20%2011_49_38.jpg

 

Standard on the left, and iridium on right.

Edited by Rebel Scum
pic added :)

if it started happening with wet weather then i'd suspect air filter getting wet causing problems with maf. have you got aftermarket air filter? seems to happen with aftermarket ones only. especially paper cone ones.

  • Author

to be honest the problem was actually a little bit worse before i got the plugs changed. although the original plugs were f**ked! and one of them had gone a yellow/green colour (haven't got a clue why). as far as the air filter goes, i do have an after market one on there (don't think its a paper 1 though) and i thought it could have been that, but the garage i took it to didn't think that was the problem. (but then they didn't give me any suggestions to what it could be either). i really think i'm going to have to take it to a specialist as no mechanic i've spoken to so far has any idea about these cars. any one no of any decent mechanics near colchester?

If you disconnect the maf and start the car it will run in a default mode but wont rev above 2000rpm. If the problem is solved then you know its the MAF. I had same fault on mine and jeff pointed me in this direction.

hi i have the same problem, (even same started occurring after spark plugs) even manages to stall on occasions, on mine i've found a few factors,

 

one is my plugs are a very low heat range, so they coke up quickly on short journeys,(worse when wet or cold) but clears as soon as it gets up to temperature,

 

another is i changed my nose panel whilst my new one is at the body shop and water is getting onto the mushroom filter, (not paper but still soaking enough water to reduce air flow)

  • Author

thanks for the advice, i will give it a try but like i said it doesn't happen all the time. and i only tends to happen when the car is moving. i know when i had my saph (god rest its soul :crying: ) i had probs with the maf and it didn't seem the same as whats happening to my z.

one of them had gone a yellow/green colour ................

any one no of any decent mechanics near colchester?

 

could be one cylinder is running lean... there are so many things that can go wrong with these cars and so a number of small problems together can make a big one...

 

there are a number of things you can do to keep your car going (from a novice point of view).. aside from the usual oil, water, air filter, plugs..

 

1 - regularly check and keep all the electrical connectors clean (particularly in the wet).

2 - check the vac / pressure in the induction (not as critical in an NA)

3 - check the usual culprits that cause bad idle... (link to Oz tech forum guide)

http://www.pexcom.com.au/z32cms/e107_plugins/content/content.php?cat.150

 

4 - take the car to Zedworld... :) you won't get better service or Knowledge for Z's anywhere in the UK. So many members on here will contest to how worth while it was making the trip.

 

good luck..

  • Author

hello again. on my way to work this morning the car started running rough again, i gave it a bill of throttle and the car replied with the loudest backfire i've heard in quite a while. it's really starting to worry me now. really think i had better find a decent garage! and fast!

  • Author

zedworld is about a 4 hour drive from me! i don't know if the car will make it the way it's running at the moment :(

i remember that there used to be a nissan specialist in maldon but can't remember what they were called, although i heard they had moved to witham a few years ago.

google says its about 160 miles and takes 3 hours.... you wont get it fixed better anywhere.... get AA cover and if it breaks down they can take you the rest of the way.... :)

 

however since its an NA it might be an easier job for someone with less Z'd knowledge.... good luck anyway.....

The garage in Maldon has long gone mate and the company no longer trades. Used to be called SE Engineering/nissan.

Just remembered that there is a very good garage in colchester. I took my zed there for a full rebuild a few years back. He is on the trading estate near 'Myland' behind the Porsche/Ferrari garages. If I remember rightly it was called Shepperd Racing. But as above, Jeff is where you really should go.

  • Author

shepperd racing! of course, i completely forgot about them. they are only round the corner aswell. osty1, you are a genius! thanks for all the help everyone!

  • Author
If you disconnect the maf ....

 

can anyone tell me or show me a photo of where the maf sensor is and what it looks like so i can disconnect and clean? please

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