78 280z idle problem

[chaseincats]

10 hours ago, Jack Pearcy said:

Well I got the pressure gauge but I can’t find a t connector anywhere, this really sucks I’ll have to look online I guess.

If you rented it from your local parts store, it should have come with at least one in their box

Edited June 29, 2019 by chaseincats

[Patcon]

How did you connect the new CTS connector?

[Jack Pearcy]

1 hour ago, Patcon said:

How did you connect the new CTS connector?

Butt connectors and a ratchet crimper

[Patcon]

54 minutes ago, Jack Pearcy said:

Butt connectors and a ratchet crimper

Would be much better to solder them and shrink wrap. Resistance is your enemy in these EFI systems

 

[Jack Pearcy]

7 hours ago, Patcon said:

Would be much better to solder them and shrink wrap. Resistance is your enemy in these EFI systems

 

You’re right but also keep in mind that the car ran fine without a hitch for a month and then this happened almost instantaneously, not a problem that progressively got worse, I’m not sure it would’ve happened like that if the CTS was the problem but I don’t know 

[Jack Pearcy]

That’s why I initially thought it was the FPR because that would’ve made sense if the diaphragm had torn or something but that wasn’t the case unfortunately

[Patcon]

23 minutes ago, Jack Pearcy said:

You’re right but also keep in mind that the car ran fine without a hitch for a month and then this happened almost instantaneously, not a problem that progressively got worse, I’m not sure it would’ve happened like that if the CTS was the problem but I don’t know 

I understand, but they won't stay good for long. Better to do it once and not have to remember to come back and redo it later.

[Jack Pearcy]

1 minute ago, Patcon said:

I understand, but they won't stay good for long. Better to do it once and not have to remember to come back and redo it later.

Of course, it’s always good to check something off the list properly. I was just wondering if maybe there’s something else that could spontaneously cause an issue like that. Just me throwing ideas around because I can’t run any real tests at the moment

[Patcon]

10 minutes ago, Jack Pearcy said:

Of course, it’s always good to check something off the list properly. I was just wondering if maybe there’s something else that could spontaneously cause an issue like that. Just me throwing ideas around because I can’t run any real tests at the moment

S30 EFI is not my forte. I know enough to be dangerous. I know resistance and corrosion seem to cause 60+% of the issues we see come across the forum. The other portion seems to be component failure and PO's "fixes"

[Jack Pearcy]

On 6/28/2019 at 2:31 PM, EuroDat said:

You could have a couple of issues that cauld cause an overfueling problem.

Most common are leaking injectors, leaking CSV or a bad temperature sensor or wiring going to the temperature sensor. The more resistance the colder the ECU thinks the engine is and compensates with more fuel. 

You seem to be getting a lot more fuel than a faulty temperature sensor would allow, but doing the checks will confirm or dismiss it. When you check it, do the check at the sensor (sensor to ground resitance) and than again at the ECU connector (Connector pin 13 to ground resistance) They should be the same. Refer to the bible for the correct resistance for temperature range.

Note: Use the 1980 Bible. It is for all models 280Z, 280ZX en 810 Maximas up to 1980.

The other book is for the 1974 to mid 1976 models.

Does the battery have to be connected for the tests?

[Dave WM]

not for the test listed above, some test will have you set up for resistance, some for voltage. The resistance test, no battery. the voltage test will be battery and key on and sometimes key start.

The FSM will detail the setting for you. There is a start enrichment test that requires the battery connected and the key to the START position.

[Jack Pearcy]

8 hours ago, Dave WM said:

not for the test listed above, some test will have you set up for resistance, some for voltage. The resistance test, no battery. the voltage test will be battery and key on and sometimes key start.

The FSM will detail the setting for you. There is a start enrichment test that requires the battery connected and the key to the START position.

I was getting no reading for the resistance test is why I asked