I'm test driving a 90 TT next week and was wondering what boost it should be running (just something else for me to check)?

 

Also, what should the temp gauge read when the car is warmed up?

 

What about idle? what rpm should it sit at when warmed up (bearing in mind that it'll probably be a cold day)?

 

Will the check engine light flash error codes when the car is started or does the ECU need to be put into 'diag mode' or something?

 

Are there any other things i can check by looking at the gauges while driving the car?

Hi Marty, don't know if this will help but my 1990 ZXTT import idles at 750rpm when warm and the temp guage stays just under half way all the time once it's up to temp. The turbo boost guage hangs around the middle when driving normally but once I floor it the guage shoots all the way to the top, which on mine reads +7.

 

Cheers

Glenn

Originally posted by marty_t3

I'm test driving a 90 TT next week and was wondering what boost it should be running (just something else for me to check)?

 

Also, what should the temp gauge read when the car is warmed up?

 

What about idle? what rpm should it sit at when warmed up (bearing in mind that it'll probably be a cold day)?

 

Will the check engine light flash error codes when the car is started or does the ECU need to be put into 'diag mode' or something?

 

Are there any other things i can check by looking at the gauges while driving the car?

Temp should be in the middle or lower.

Around 750 RPM is ideal, however mine runsat 900 at the moment, but I guess its just a contact clean up and a TB clean should sort that out.

You need to enter Diag mode to see the error codes. Unbolt the floor panel (passenger side foot well). Turn the screw on the side of the ECU fully clockwise leave for 2 seconds and then turn fully anticlockwise. Turn the ignition on (do not start the car). The ECU LED will flash as will the eninge check light. You are looking for 5 long flashes followed by 5 short flashes. This means all clear, anything else then there is a problem.

If I were you I would get someone else to check the car mechanically. The last thing you want to do is buy a 300zx that is kicking out blue smoke because the turbo seal are blown.

Make sure that when you vie the car it is in the morning, so the car is still cold. If the car has purposly been warmed up awaiting your arrival, walk away.

Originally posted by smw1

Temp should be in the middle or lower.

Around 750 RPM is ideal, however mine runsat 900 at the moment, but I guess its just a contact clean up and a TB clean should sort that out.

You need to enter Diag mode to see the error codes. Unbolt the floor panel (passenger side foot well). Turn the screw on the side of the ECU fully clockwise leave for 2 seconds and then turn fully anticlockwise. Turn the ignition on (do not start the car). The ECU LED will flash as will the eninge check light. You are looking for 5 long flashes followed by 5 short flashes. This means all clear, anything else then there is a problem.

If I were you I would get someone else to check the car mechanically. The last thing you want to do is buy a 300zx that is kicking out blue smoke because the turbo seal are blown.

Make sure that when you vie the car it is in the morning, so the car is still cold. If the car has purposly been warmed up awaiting your arrival, walk away.

 

 

There is an easier way :- http://www.twinturbo.net/ttnetfaq/FAQpages/ECUdiagnostics.html