Pete (TurboZ) and Graham (GrahamS) connected my car upto Datascan the other month and found, that the timing stayed at 25 degrees, even when the car was left running and reached 81 temp. Any ideas what could be causing this?

 

Car is a UK, manual conversion, has Koyo rad and Greddy SMIC.

 

Thanks in advance.

 

Barry

forgot to mention, also has a Profec B11 fitted, plumbed in, but the car hasnt been chipped yet.

 

Barry

Flippin eck mate thats well out! having such advancement is not too bad low down, in fact the car will be quick, however higher up the rev range it would lean out quite badly.

Seeing as where you are, i'd pop along to phil at C+S Woods and have him check the timing with a strobe and adjust back to 15 degrees.

I know from my Silvia days that if a TPS was bad/faulty it would gradually knock the timing in either direction, so a possibility on the zed too.

Sorry can't be more help mate.

smithy

i think the datascan only tells you the timing reading the cas is sending out. could be a faulty cas. get a srobe on it to confirm 10 out it quite a bit.!

Thanks Paul, the car is due to go to C and S Woods, for the engine rebuild, so will get Phil to look at it then for me.

 

Regarding the email last week, I will take a pic of the brake booster pipes over the weekend, so I can get the order placed with for those bits I mentioned.

 

Thanks

 

Barry

i think the datascan only tells you the timing reading the cas is sending out. could be a faulty cas. get a srobe on it to confirm 10 out it quite a bit.!

 

 

Thanks Hellraiser, to be honest havent used the car in the past 2 months.

 

Barry

Thanks Hellraiser, to be honest havent used the car in the past 2 months.

 

Barry

hope its somthing simple buddy . all the best and good luck

Barry, talk to Pete.

 

He had to set the timing on his a couple of weeks ago using a strobe light 'cos his CAS was set wrong

.

It'll still be fresh in his memory LOL.

Check the neutral switch in the gearbox, if this is inoperative or disconnected you will get a readout timing of 25 deg when warm, although a timing light may confirm the actual engine timing is OK. ( 15 Deg )

 

This also can happen when auto to manual convertions are done if the neutral switch is left unconnected.

 

Daveman

If I remember rightly the ECU just presumes the engine is at a base of 15 degrees so checking the engine timing with a strobe light, although worth doing anyway, I dont think it is the problem.

 

For some reason the ECU wants to keep the timing advanced. Could be because of the sensor DaveMan mentioned.

 

Give me a shout on Messenger later barry.

 

Pete

If datascan shows 25deg, then the timing light should ALSO show 25deg!!! The CAS is used to set the reference points so the ecu can set the timing correctly, NOT so the ECU knows what the timing is!!!!

 

The ECU will calculate timing based on a number of sensor values. Check things like TPS setting etc...

If datascan shows 25deg, then the timing light should ALSO show 25deg!!! The CAS is used to set the reference points so the ecu can set the timing correctly, NOT so the ECU knows what the timing is!!!!

 

The ECU will calculate timing based on a number of sensor values. Check things like TPS setting etc...

Andy, what should the TPS be reading? 0.44 on idle (closed throttle) and is it 4v or 5v on wide open throttle?

as Daveman says, the neutral switch of the gearbox is not connected to the ECU.

This is a VERY common fault on AT -> MT converted cars

 

http://300zx.co.uk/forums/showthread.php?t=63335

Thanks everyone with all your suggestions and help.

 

Barry