mrfixit.joe

Thanks and had just figured it out

You referred to an AAR can you explain what device you’re talking about there? I don’t recognize that term.

Thanks for responding again hear some more clarifying parts so I do have a fuel pressure gauge under the hood and I use it for troubleshooting after the car was restored 15 years ago. During cranking I do not see pressure so I started checking the pump only getting 9.6 V during cranking if I use a power probe and put 12 V on it, it runs the car starts and then once it switches to the run cycle, it keeps running. I installed the new relay behind the passenger seat right where the connection goes to the fuel pump. I’m using the 9 V that comes during cranking as the control on this new relay ran a fused line back to a fused junction box that I added to power some other things in the car. So all safety protocols are sterile in place during cranking the 9 V energizes the relay once the engine starts in the airflow meter takes over the control of the fuel pump the voltage is 11 811 nine and once the alternator kicks in it goes over 12 V and the pump is running fine. I am also wondering if it is a weak pump I was hoping somebody could test their voltage during cranking and tell me what they’re saying.

I found the drop happens at the relay's incoming voltage when cranking the engine. I have wired in a second relay for now as I keep investigating.

Responding why I am asking. Car would not start during troubleshooting found if I applied 12 V to the fuel pump it would run so I checked the voltage during start procedure and found only 9.810 V. I’m now working my way back through every connection. Checking to see if I can find exactly where the voltage drop is occurring.

Thanks I already replace the Ignition relay. I will keep troubleshooting

77 280z I am only seeing 10 volts at the pump battery is full charged. Can anyone tell me if this is normal

if thereh is a plastic dash cover then it will not come out the front.

I agree that it sounds like your are running lean. Here is simple test you can do if you are not good with and ohm meter. First turn up you idle to about 1800. Then disconnect the water temp sensor and it is the one with the black wires. the idle should drop back to about 900, and then take it for a ride and if it seems like it has power than I would looking real hard at the AFM. do not leave it set up like this because it will carbon foul the plugs.

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.

I checkd this by running a ohm it to the cold start valve to make sue I had them correct. If you are sure which one the green wires go to I would mind checking again.

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

ok I have and update if i disconnect the temp sensor the idle drops. I can turn the idle up and the car runs rough but it has the pwoer again. it is agin running rich . I hope this helps so you can give me and idea what to check next.

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

Thanks for your help I got it working. All i did was clean all the connectors in including the fuse box connection and it started working.