Almost fifty and I finally got a Z. I remember seeing my first 240z when I was delivering newspapers on my bicycle. I would drive by the car daily. It was orange, had a wooden steering wheel, and the inside was truly a cockpit. It was on the same lot as the Smoky and the Bandit Trans Am, but it was easy for me to see which car I liked. Datsun... hands down! I recently aquired a 1978 280z. My perceptons form early youth proved true. This car is 30 years old and it is the most fun I have ever had driving an automobile. However, I have been experiencing problems lately. I had the gas tank cleaned and sealed, put a new fuel filter and fuel pressure regulator on, new plugs, wires, coil, fusable links. I am experiencing loss of power after the vehicle runs for a few minutes. Could it be the injectors? After it runs a few minutes the power diminishes. The motor does not appear to be very hot, but the catalitic convertor does alot of pinging like it is hot. Could the catalitic convertor be clogging the system as it heats up?

Help!

cls

Check the connection at your temperature sensor and the temperature sensor itself. Also make sure you have a good connection where the harness plugs into the Air Flow Meter. (Thanks member BOMBAYBOB for that suggestion)

you're talking about the air temperature sensor, right? Can the sensor be tested?

I believe Stephen is speaking of the Coolant Tempature Sensor, located in the thermostat housing. There are 2 sensors in there, the other is the thermotime switch, it is the smaller of the 2. Both can be tested using a multimeter, you will need a copy of the factory service manual or the "Fuel Injection Bible" though. I think you can download a copy of the FSM from here...

http://carfiche.com/manuals023/cars/

When you check the sensors, clean the contacts to them very well. Also, follow the wires up from the 2 sensors, the will merge together and then plug in using bullet connectors. Pull those apart and make sure they are very clean as well, I've heard they are a culprit sometimes. Hope this helps.

The air tempature sensor is located inside the A.F.M. THe harness plugs into the bottom of the AFM, clean it very well too.

Edited December 16, 200816 yr by MEZZZ

you're talking about the air temperature sensor, right? Can the sensor be tested?

No the water temperature sensor. If it's bad or has a bad connection it will allow the car to start and run when it's cold but won't allow the fuel mixture to be lean enough to ren properly once the car reaches operating temperature. The test procedure for it is on page EF-32 in the Engine Fuel section of the service manual. If you don't have one you can download it here.

Edited December 18, 200816 yr by sblake01

MEZZZ's response was faster than mine but his link doesn't have a 78 FSM.

Thanks to the both of you. I dont have time to work on the car till this weekend, but I know where to start. I'll let you guys know.

Chris

MEZZZ's response was faster than mine but his link doesn't have a 78 FSM.

, thats why YOU are the king on here, Stephen, I pale in your shadow.

Plus, I am only repeating everything you taught me so far!

You have been spot on with 99% for me and I am very appreciative.

If I dont communicate with you before, heres hoping you and the Mrs have a great holiday!

Mark, I'm hardly a king but I appreciate the comment. I guess I've been around these cars long enough to learn what works and doesn't work (at least for me) and try to pass on that info in hopes that it helps someone. Thank you for the holiday wish and I wish the same for you as well as for anyone who reads this.