I have another post about a running issue with son's '96 na. I thought about replacing the temp sensor. Can't get it locally so I pulled it and tested it. At aprox 89 degrees in the garage I was getting 1600Kohm. according a post on this site I think that is right in line with normal. I applied cold and heat and the resistance went up and down accordingly. NOW that being said, does the sensor perform normally while the car is running? Don't know.

anyone?

ECT's don't usually drift much over time like, say, knock sensors do. They're just NTC thermistors, nothing fancy. So if it still reads correctly at one point, it should still read right across the range. The only additional check you can do is heat it up a bit and make sure the ohm reading moves. You can do that in situ using engine heat, just pull the connector and ohm it cold, then warm the engine and make sure the reading changes.

I did test by heating and cooling. I used an ice pack to cool and a mini torch to heat. Sensor was in a deep socket and I heated the socket from the outside. Didn't want to damage the sensor. I know a faulty temp sensor can cause running issues and wanted to eliminate this.

This car is really starting to get on my nerves.

Thanks for the response.

I'm no classic-Z expert, but a lot of the Nissans in that era had two separate ECT's, one for the gauge and one on a cylinder head. The one on the head was the one the ECM used to govern cold-enrichment. Maybe one of the Z mavens here can clarify what you should be checking.

^ This is correct, partly. The two sensors on the Z32 are side by side in the water pipe on the front of the engine. The single pin is for the gauge the 2-pin is for the ECU.

Correct. The one I tested is the 2 pin sensor

NolimitZ32 wrote: ↑

Thu Jul 22, 2021 6:05 am

^ This is correct, partly. The two sensors on the Z32 are side by side in the water pipe on the front of the engine. The single pin is for the gauge the 2-pin is for the ECU.

NoLimit to the rescue, tyvm. Do you happen to know what the voltage range should be on the ECU sensor? The OP should probably check that next.

scottgas wrote: ↑

Thu Jul 22, 2021 6:39 am

Correct. The one I tested is the 2 pin sensor

Per above, resistance in the wiring or connections can make a healthy sensor read colder than it should by weakening the pull-down current from the sensor to the ECM's pull-up. You might have a wiring issue.

Scott, with the number of issues you've had with this car I think a complete maintenance update is order. I've lost track of what you have changed and what you haven't. If you were closer I may have offered to come by at this point and just do a full top to bottom health check. I will tell you that in my experience a lot of issues are caused by much more simple issues than people think. For me it's been pinched injector o rings, loose hose clamps, cracked hoses, and other simple but annoying BS like that. It all drove me to where I now always install new consumables when I work on my cars. Maybe if you put together a complete rundown of what you've done and the symptoms experienced and fixed at each junction you could hone in on where the issues may be coming from. Its really hard to follow all the different threads. I don't want to merge them because the forum software uses time to align the posts so it'll end up a jumbled mess with multiple posts from multiple threads in the same timeline.

VStar, I do not know, All I remember is that the TPS is 0-5, I have a horrible memory that's why I have the FSMs for all my vehicles downloaded in case the internet ceases to exist or one of the mfgs issues a cease and desist.

https://www.nicoclub.com/service-manual ... 6%2Fec.pdf

goto page EC118

NolimitZ32 wrote: ↑

Thu Jul 22, 2021 9:13 am

I have a horrible memory that's why I have the FSMs for all my vehicles downloaded in case the internet ceases to exist or one of the mfgs issues a cease and desist.

Same problem here. Memory is the first thing to go when you get old, and the second thing is.... uh..... it will come to me....

NolimitZ32 wrote: ↑

Thu Jul 22, 2021 9:13 am

Scott, with the number of issues you've had with this car I think a complete maintenance update is order. I've lost track of what you have changed and what you haven't. If you were closer I may have offered to come by at this point and just do a full top to bottom health check. I will tell you that in my experience a lot of issues are caused by much more simple issues than people think. For me it's been pinched injector o rings, loose hose clamps, cracked hoses, and other simple but annoying BS like that. It all drove me to where I now always install new consumables when I work on my cars. Maybe if you put together a complete rundown of what you've done and the symptoms experienced and fixed at each junction you could hone in on where the issues may be coming from. Its really hard to follow all the different threads. I don't want to merge them because the forum software uses time to align the posts so it'll end up a jumbled mess with multiple posts from multiple threads in the same timeline.

VStar, I do not know, All I remember is that the TPS is 0-5, I have a horrible memory that's why I have the FSMs for all my vehicles downloaded in case the internet ceases to exist or one of the mfgs issues a cease and desist.

So, the car currently has 80,000 miles. We bought it in January 2018 with 47,000 miles. The previous owner is a retired lawyer. He said he had the whole front of the engine serviced at his dealer. Timing belt, water pump, service belts, tensioners, etc. Not positive all that is involved with a front end service on a Z32. He said he also had iridium plugs installed at that time. Trans and diff were also serviced.

I personally have replaced the fuel pump. That was my 1st though when the issues started. Didn't fix it. Next was the fuel pump controller. A used one from Z1 Motorsport. That also didn't fix it. Removed, disassembled, cleaned, and re-installed the IACV. That didn't fix it. Honestly the IACV was in good shape. A lil blackish coloring inside but no actual carbon. Next I bought the boost leak tool from Z1 and we chased intake system leaks, may of them. Replaced the cross over tube o-rings as we were getting leaks through a few of the bolts. Still problems. I am most of the way through checking electrical connectors. Have the connectors on the backside of the engine left to check. So far all the connectors have been in really good shape. No corrosion in any of them and no cracked plugs. Wiring also looks to be in good shape, at least on the outside. As mentioned above, I check resistance for the temp sensor and it checked out. Next will probably be checking the TPS.

My son has been trying to drive the car daily to see if we can get the check engine light to come back on then check for codes. No luck so far and also we have had rain almost every day for 3 weeks.

The front end service usually includes water pump, timing belt, idlers, tensioner, and thermostat. Some change hoses and clamps, others reuse. (in response to your other thread) The TPS is known to sometimes have issues when a flat spot or worn spot develops on the contact surface and it will display symptoms not unlike yours where if the gas is slowly pressed nothing out of the ordinary happens but if you hit the gas hard the momentary loss of contact is enough to wreak havoc on your car. MAF sees tons of air but the TPS thinks the throttle is closed which throws the whole system for a loop. You can try to replicate the TPS signal but you need something that will log the output data or a multimeter that has a ridiculously fast refresh rate if you're looking at it live. Not sure injectors will do anything, especially since the 96 has phase 2 units which are way more reliable than the pintle style phase 1s.

Ok, thanks for the response. When we checked the TPS we did it multiple times with the same results. I do realize that as you drive it could still act up. I may just change the TPS too. Son goes back to college in a couple weeks and hoping to have this thing fixed

The TPS has to be tested in place, hooked up to the car with the car running. Or with a steady 5v source.

we followed TPS testing procedures listed on this site. Connected with 5 volts, key switched on but not running. I probed the wire that needed testing. Slowly opened throttle body and held, multiple times and all numbers were good

Hmm. I'm stumped man.

that makes 2 of us. Injectors will be here in a couple days. Probably going to replace the TPS and temp sensor as well. Still have to look into the MAF. I got into a traffic accident 2 days ago so not moving too well right now. May have to talk my son through the steps and him physically do the work

I'm sorry to hear that man, I hope you're ok.

So far I'm ok. Left forearm tore up from airbag and fra turned sternum. Follow up with surgeon today to see if surgery is needed. ER Dr said surgery for this is rarely needed.

On a different note, injectors came in yesterday. Will probably tackle on Sunday

I hope the ER doctor was right. speedy recovery to you sir.

I'm assuming your going to pull the plenum for the injectors, do you have a new gasket, the paper gasket never survives. Also use lots of lube on the injector o-rings when installing back in the rails, those pinch really easy.

Surgeon said no need for surgery.

Hadn't thought about the manifold. Will have to order the gasket. Thanks for the tip

If you havent performed the coolant bypass, this is the perfect opportunity to do it. Removes lots of potential leak points from the coolant system.

ok, what is the coolant bypass

working on getting the plenum off. what a royal PITA this is

is there a way to delete the EGR system?

Yes, there are delete kits, not sure again how the 96 will react. My 92 hasn't had one for years.