My 300zx tt has had a low idle speed for several months, around 600rpm. over the last week or so, this has slipped further down, it was 500rpm for a while, today it was suddenly at 300 and then it stalled. Now it won't idle at all, it will stall immediately when I don't give any pedal.

 

I checked the cables coming out of the TPS, one of them appeared broken so I fitted a new connector. No effect on the idle speed whatsoever. I also cleaned out some green gunge from the TPS connectors, but it wasn't much.

 

The engine runs normally when I press the accelerator, only the idle seems to have problem.

 

I guess it has nothing to do with it, but the aircon is seized. the aircon belt is removed but nothing else is done to the aircon unit. switching on or off the aircon from inside the car doesn't make any difference.

 

Any ideas of what it could be? This problem came gradually, not suddenly...

My 300zx tt has had a low idle speed for several months, around 600rpm. over the last week or so, this has slipped further down, it was 500rpm for a while, today it was suddenly at 300 and then it stalled. Now it won't idle at all, it will stall immediately when I don't give any pedal.

 

I checked the cables coming out of the TPS, one of them appeared broken so I fitted a new connector. No effect on the idle speed whatsoever. I also cleaned out some green gunge from the TPS connectors, but it wasn't much.

 

The engine runs normally when I press the accelerator, only the idle seems to have problem.

 

I guess it has nothing to do with it, but the aircon is seized. the aircon belt is removed but nothing else is done to the aircon unit. switching on or off the aircon from inside the car doesn't make any difference.

 

Any ideas of what it could be? This problem came gradually, not suddenly...

 

sounds like it is the i.a.a unit (aka idle air ajusting unit) could be gunged up or might not be getting the preset signal from e.c.u or it could be dirty ash tray :D

clean i.a.a as brian says remove connector,at worse you may need to strip actual unit down and clean it,theres a link on tt.net for how to

 

just clean all connections possible to like MAF IAA TPS

 

there is an ajustment screw on the side of the IAA unit that will raise the idle by turning clockwise or anti reset ecu whilst your at it,so it can learn the new values

So where is the IAA unit? ive checked the engine by numbers section but it aint there.

 

Cheers

So where is the IAA unit? ive checked the engine by numbers section but it aint there.

 

Cheers

 

 

heres link on howe to ajust fix etc http://www.twinturbo.net/ttnettech/iaa/iaa.html

as the pic of car is US its showing iaa on left side iaa is situated to the left at the back of the engine next to battery,battery removal is required and its a bit fiddly to remove but ok

Posted by greg:

"there is an ajustment screw on the side of the IAA unit that will raise the idle by TUNING CLOCKWISE" :nelson:

 

That would be ANTI -clockwise if you want to RAISE the base tick over :D

 

Jeff TT

Posted by greg:

"there is an ajustment screw on the side of the IAA unit that will raise the idle by TUNING CLOCKWISE" :nelson:

 

That would be ANTI -clockwise if you want to RAISE the base tick over :D

 

Jeff TT

 

trust you :D im learning theres a differance,besides i gave him the link for ajustments and how to