Jump to content
Email-only Log-Ins Coming in December ×

IGNORED

problem after changing water tep sensor


mrfixit.joe

Recommended Posts

77z I put it back on the road after 10 yrs. it was runnig good but found it was running very rich and was only getting 14 MPG. everthing else was good.

change the water temp sensor because i believed it was not allowing engine to lean out after warm up. the engine starts great and I had to reset the idle down. it revs fine but as soon as i put a load on it it pops and bucks.

I replace the plugs and checked the timming. I can not put the old one back in because it broke.

I hope somebody has an idea.

joe D

Edited by mrfixit.joe
Link to comment
Share on other sites


1972 240Zs came with carburetors, so your post does not make sense. Do you have an EFI engine in the car now?

If you do have EFI, then you need a properly functioning temperature sensor. For starters, measure the resistance at the ECU plug and compare it to the values in the chart in the FSM.

Link to comment
Share on other sites

sorry for the confusion my Z is a 1977 280Z.I belive the sensor is working correctly and there is a different problem. I just checked and adjusted the TPS and need to test drive it but it is poring right now.

Joe D

Edited by mrfixit.joe
Link to comment
Share on other sites

Ok here is what I found. The car was running with a bad water temp sensor, so it was real rich. After changing it and the it getting the proper fuel mix caused a lack of power and poping. This ended up was being caused by a bad AFM. The bad sensor was masking the problem with the AFM .

I had a spare from a parts car. Ran it through all the test and it checked out, so I put it in and she's running good and lean.

Thank you all for your help.

Link to comment
Share on other sites

I have a similar concern with my '78 280Z. It sat for 7 years and I just got it running again. It also pops and backfires when I try to do a normal accel from a stop. If I hammer it, it runs great. This is my first Datsun FI system. I have aways worked with Solexes, Webers, SU's or Hitachi carbs. I have changed AFM and computers and the malady still exists. I bought a new water temp sensor and think that may be the problem. Mine is for the 80's ZX's. Will it work on my '78?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Who's Online   2 Members, 0 Anonymous, 914 Guests (See full list)

×
×
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy and Guidelines. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.