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Z32 Timing Issue
Posted: Tue Sep 30, 2008 3:36 pm
by zrated
Hi Guys,
I've got an issue with a Z32 TT Manual.... When I hold the car at light throttle it hesitates and as you can see by the log, the timing is going crazy!
The timing goes from about 60 to -9 and all in between. This problem I've never faced before... It will only do it at light/steady throttle position. If I stab the throttle it will rev up and down without a problem...
The TPS is set properly (0.5v @ idle) and the base timing has been checked/adjusted.
I suspect that the timing belt might be out, or the CAS is stuffed....???
Any suggestions?
Posted: Tue Sep 30, 2008 7:51 pm
by zrated
anyone?
Posted: Tue Sep 30, 2008 9:48 pm
by Eric
does this car have a 16 bit ECU ?
..in that case this timing behaviour is normal at idle.
you could try resetting the closed throttle switch setting in the ecu (disconnect the seperate connector from the TPS for 5 seconds with the engine running)
-Eric
Posted: Tue Sep 30, 2008 10:11 pm
by zrated
Eric wrote:does this car have a 16 bit ECU ?
..in that case this timing behaviour is normal at idle.
you could try resetting the closed throttle switch setting in the ecu (disconnect the seperate connector from the TPS for 5 seconds with the engine running)
-Eric
yep, done that... but i don't think it's normal for the timing to fluctuate that much while the car is cruising/light throttle (not just at idle).
It's a 16bit, yeah.. that's a stock Z32 pre 93 model isn't it?
Posted: Tue Sep 30, 2008 10:32 pm
by Eric
>> It's a 16bit, yeah.. that's a stock Z32 pre 93 model isn't it?
pre 93/94 are 8-bit (eprom type ECU's)
later ECU's are 16 bit
if you have the 8-bit ecu, the timing behaviour in the graphs you posted isn't normal.
In that case the CAS is the first suspect, but your rpm signal looks normal.
have you tried resyncing the maps in the Nistune board ?
Posted: Tue Sep 30, 2008 11:09 pm
by zrated
Eric wrote:>> It's a 16bit, yeah.. that's a stock Z32 pre 93 model isn't it?
pre 93/94 are 8-bit (eprom type ECU's)
later ECU's are 16 bit
if you have the 8-bit ecu, the timing behaviour in the graphs you posted isn't normal.
In that case the CAS is the first suspect, but your rpm signal looks normal.
have you tried resyncing the maps in the Nistune board ?
My bad... yes it's an 8 bit ECU.
No it's definitely not normal and yes, I've tried resyncing the maps, etc. Still no luck. I really this there is something wrong outside of the ECU (ie CAS or timing). The car has just recently been rebuilt so I gather that the customer may have installed the timing belt incorrectly or maybe the CAS is just faulty.