Continuation of starting woes

[NC Tom]

Happy New Year!

 

It's been nearly four weeks since my last post about this ongoing issue. But, that's okay, because I have collected some  additional data/symptoms/etc.

 

Here is a video of the engine turning over, but not starting, as requested by @89 MJ

 

This video was taken a few days prior to Christmas 2024. After this video I let the MJ roll forward a bit and it started. It's done that before

so I didn't question it. Just glad it started.

 

The next day, it started fine and I drove it to work. Leaving work, it wouldn't start. The parking lot is sloped, so I tried letting it roll backwards a bit, but no luck this time. At this point, I was in the middle of the parking lot. I put it in Neutral and a couple guys helped me push it out of the way. During the pushing, one of the guys said, "try it now." and it started. Drove home. The next day, the same thing. Turnover, no start. I primed the fuel pump three times and it started.

 

I started thinking about the conditions under which it would and wouldn't start.

At home, it's parked on mostly flat ground with a slight nose-down incline. At work, it's parked with a solid nose-up incline.

When I got to work, I backed in, so I had a good nose-down incline. Started fine at end of day. Found an area at home to park nose-down too. Also started fine. Up until yesterday, it has been starting and running well for several weeks as long as it's on an incline, nose-down. The only thing that has changed now is that the outside temps have a dropped a lot over the past couple of days. Wouldn't start yesterday. 13 degrees this morning and no starting. It's still parked nose-down.

 

The only other oddball thing is that it will occasionally stall when sitting in traffic for a good while. However, if I put it in Neutral while sitting, it won't stall.

 

I'm not the gear-head that so many of you guys are, but I'm thinking it's fuel delivery. Likely, my brand new fuel pump is not so good.

 

Thoughts?

 

[eaglescout526]

Wait…is this an automatic? If it is maybe we can suspect that the NSS is corroded or dirty inside. 

[NC Tom]

2 minutes ago, eaglescout526 said:

Wait…is this an automatic? If it is maybe we can suspect that the NSS is corroded or dirty inside. 

Yes. Auto.

[89 MJ]

Ok, the cranking rpm in the video sounds about right, maybe a little on the slow side, but definitely quick enough for it to start. 
 

I agree that it could be the NSS. Maybe pull that and clean it and both sides of the connector. Check out the wiring too, make sure there are no damaged spots on the NSS part of the harness, that sort of thing. 
 

occasionally stalling in traffic unless it’s in neutral makes me wonder about the idle speed. Have you touched the idle screw on the throttle body ever? Do you have a rough idea of what it idles at?

[NC Tom]

3 minutes ago, 89 MJ said:

Ok, the cranking rpm in the video sounds about right, maybe a little on the slow side, but definitely quick enough for it to start. 
 

I agree that it could be the NSS. Maybe pull that and clean it and both sides of the connector. Check out the wiring too, make sure there are no damaged spots on the NSS part of the harness, that sort of thing. 
 

occasionally stalling in traffic unless it’s in neutral makes me wonder about the idle speed. Have you touched the idle screw on the throttle body ever? Do you have a rough idea of what it idles at?

 

Ok, I'll check the NSS. I have not, intentionally, adjusted idle screw. I do not know idle numbers.

 

BTW, I just looked through your videos and such. I gotta say, I am truly jealous of your mechanical talents. And that Eagle is sweeeeet! I'm 58 and I remember when they first came out. I've always really liked the SX4!

[llhat]

not sure i'll help much, but...

have you tested fuel pressure on the rail during this no start condition?

 

other basic tests... Instructions on site

  CPS output

  Spark?

 

think the red herring here is the 'rolling' and then firing...

IMHO, probably not NSS

 

Stalling...  Idle air controller, cleaning Throttle body and the IAC port 

the MAP sensor and vacuum line connections

 

Possible leaking injector and 'flooding"?  Have you tried crank on Wide Open Throttle to initiate the 'flood' start in ECU??

 

Yeah these no cranks can be PITA,  my recent experience paralled  could hear fuel pump run, but NO pressure at rail.

 

its going now though.

 

 

[NC Tom]

3 minutes ago, llhat said:

not sure i'll help much, but...

have you tested fuel pressure on the rail during this no start condition?

 

other basic tests... Instructions on site

  CPS output

  Spark?

 

think the red herring here is the 'rolling' and then firing...

IMHO, probably not NSS

 

Stalling...  Idle air controller, cleaning Throttle body and the IAC port 

the MAP sensor and vacuum line connections

 

Possible leaking injector and 'flooding"?  Have you tried crank on Wide Open Throttle to initiate the 'flood' start in ECU??

 

Yeah these no cranks can be PITA,  my recent experience paralled  could hear fuel pump run, but NO pressure at rail.

 

its going now though.

 

 

Sure, checked all the above. I checked the fuel pressure at 30+. It may be a little low. I don't know when it's low enough to be an issue.

[89 MJ]

1 minute ago, NC Tom said:

 

Ok, I'll check the NSS. I have not, intentionally, adjusted idle screw. I do not know idle numbers.

 

BTW, I just looked through your videos and such. I gotta say, I am truly jealous of your mechanical talents. And that Eagle is sweeeeet! I'm 58 and I remember when they first came out. I've always really liked the SX4!

If I were to guess, your idle speed should be somewhere around 900 rpm. I’d also recommend cleaning up the throttle body. Best part about cleaning up the TB will be bringing it inside since it’s cold out haha. Here’s a thread on cleaning it and the IAC. 

 

Thank you for the kind words! If you think my Eagle is cool, you should check out Eagle_SX4’s car. 

 

 

11 minutes ago, llhat said:

think the red herring here is the 'rolling' and then firing...

IMHO, probably not NSS

 

Stalling...  Idle air controller, cleaning Throttle body and the IAC port 

the MAP sensor and vacuum line connections

 

Possible leaking injector and 'flooding"?  Have you tried crank on Wide Open Throttle to initiate the 'flood' start in ECU??

I’m thinking the rolling could just be it getting jostled to where there is contact at the NSS. 
 

Good thinking on the vac lines and TB stuff. 
 

If I recall correctly, we didn’t think it was flooding because it would seem like the issue would be worse after the engine was just run. The no start condition seems to happen when it’s sat overnight. 

[NC Tom]

6 minutes ago, 89 MJ said:

If I recall correctly, we didn’t think it was flooding because it would seem like the issue would be worse after the engine was just run. The no start condition seems to happen when it’s sat overnight. 

What's really interesting is that it seems like if I do not start her every day, this happens. Miss one day and all bets are off.

 

It is cold! Especially for NC! I really need to invest in a garage. I don't mind the work, just not so much when there is snow on the ground.

[89 MJ]

4 minutes ago, NC Tom said:

What's really interesting is that it seems like if I do not start her every day, this happens. Miss one day and all bets are off.

 

It is cold! Especially for NC! I really need to invest in a garage. I don't mind the work, just not so much when there is snow on the ground.

That is super weird. 
I can’t say that I blame you there, I don’t care for the cold weather at all. 

[llhat]

i just do not see the correlation between the NSS and the vehicle running. 

The circuits on the wiring diagram just do not seem to go to the ECU..controlling the spark and the fuel.  but it does control the starting circuit, the reverse lights, and the transmission controls.

If you unplug the NSS at the connector under the hood, the starter would not engage, but I'd think if you unplugged with the engine running, it would continue to do so, but the transmission would only shift with the manual lever.

 

temp 'could' have an effect on connections, as well as the CPS response and its output,   and "maybe" circuits in the ignition module, etc

 

cold here in the piedmont too.....