right my z seems to be running fine but every now and again (few weeks)

i would be giving it a little paced driving and it pulls like a train. say over a 7 mile journey mixed carrageway and normal roads.

when i get home turn off. say i go out again (normal to paced driving) the cat light would flicker on and off up to being fully on! (still running fine pulling great etc.)

this will then flicker then go off. ok

 

keep driving comes on full stays on till i get home them when i pull up turn my lights off the cat light dims or goes off. if i turn the lights back on the cat light comes on. but its also controlled by the revs/throttle.

 

its such a strange thing and very difficult to explain thats why i asked for somebody to have a look at my datalog as it happened last night and i did a data log while sat outside.

 

what do you recon it could be im :confused:

This happens to me every now and then. As far as I know, the cat lights just monitor the temperature of the cats via the thermocouples stuck in the side of them. These are in no way connected to the ECU (anyone correct me if I'm wrong) and are only on the Jap spec (again correct me). I would not worry too much about them as if it was a UK spec, you wouldn't know any different. Having said that, someone may know different?

iknow the cat light is for when they get too hot. eg excess fuel being burned in the cats causing them to overheat. but i dont know how unless for a split second a coilpack or something drops out dumping fuel into the exhaust.

i plan on getting decats at some ppoint but i would like to solve this problem beforehand.

Bad earth to the cat temp warning light controller perhaps?

just get rid of the cats mate, that solves the probelm buy removing the problem.

 

bring on the noise!

 

nick

just get rid of the cats mate, that solves the probelm buy removing the problem.

 

bring on the noise!

 

nick

haha its noisy anyway. :rofl:

 

i was just thinking its a problem as it is a warning!

decatting would mask this warning then solve it to be honest. but if its just an electrical earth gremlin then decatting will solve it if you know what i mean.

Would suggest an earth since the conditions the light comes on under, are when the battery voltage is lower. Not sure where the earth will be for this circuit though. Out of interest, have you ever had a heater matrix go pop? This would dump coolant into the footwell and could well corrode one of the earth connections... If it is an earth issue then the light may still do the same even with the sensors out (although you could always just remove the bulb :D )

Would suggest an earth since the conditions the light comes on under, are when the battery voltage is lower. Not sure where the earth will be for this circuit though. Out of interest, have you ever had a heater matrix go pop? This would dump coolant into the footwell and could well corrode one of the earth connections... If it is an earth issue then the light may still do the same even with the sensors out (although you could always just remove the bulb :D )

not that i know of. its just odd this is the first time i have noticed its reaction to turning the lights off tho as its also the first time its been on long enough for me to mess about with a few things.

Maybe check the battery voltage with the lights on and off and see if there is a significant difference?

read my mind there andy. its most likely electrical problem on the cat sensors. obviously getting rid of the cats removes the problem. Wouldnt be anything like a coil missing a beat, you'd feel the miss fire.

 

dont forget the cats are probably on their last legs anyway, they are about 15 years old dont forget!

 

but as andy said, could be well worth checking your earths, you may figure out some of the other "characteristics" the zed has i down to bad earthing

 

 

nick

get rid of the cats and install dogs instead, much more friendly

get rid of the cats and install dogs instead, much more friendly

ahh but you have to care for a dog more cos they are more dependent than cats ;)

my two cats are 15 years old and have only just become a burdon. :p

 

 

 

andy n nick which earths are best to check as there are bloody hundreds of them! any obvious ones that have been known to cause problems.

oh and would now be a good time to get an earth kit off of shrimpy

Earthing kits are always a reasonable idea on a 15yr old plus car so for the price then why not! Although this will be a seperate circuit (body only rather than engine). It could cure the problem but I doubt it. There's earths everywhere lol, I'd start under the centre armrest area though since thats where the unit is (I think). Check below the stereo etc, drivers floorwell. They're the main ones from memory. Actually if someone has had a drink thats spilt in the centre armrest area than that would be a likely cause... You ever seen what coke (the drink :rolleyes: lol) does to a circuit board? Seen a 350Z with a completely trashed relay board/power distribution unit thanks to coke being spilt on the dash 2 months prior - that was fun tracing I can tell you :D

Earthing kits are always a reasonable idea on a 15yr old plus car so for the price then why not! Although this will be a seperate circuit (body only rather than engine). It could cure the problem but I doubt it. There's earths everywhere lol, I'd start under the centre armrest area though since thats where the unit is (I think). Check below the stereo etc, drivers floorwell. They're the main ones from memory. Actually if someone has had a drink thats spilt in the centre armrest area than that would be a likely cause... You ever seen what coke (the drink :rolleyes: lol) does to a circuit board? Seen a 350Z with a completely trashed relay board/power distribution unit thanks to coke being spilt on the dash 2 months prior - that was fun tracing I can tell you :D

thanks mate your a star. :hyper: