810 Maxima L24 heat soak starting issue

[HRH]

So the Maxima has been running great, but I've only been starting it up and driving for a while, then shutting down and letting the engine go completely cold after driving again.  Today I did some errand running in it and I found an annoyance.

 

When I shut the car down (running fine) for a period of 5-30 minutes and it heat soaks, I go to restart and she runs quite poorly.  I'll crank the key without the throttle, she'll start then die.  Then I do it again and feather it a bit and keep her going, but she just runs like crap.  If I floor it, she does increase engine speed.  After about a minute of this, the motor starts running great again, so something is definitely getting cooler.

 

Calling the Datsun guru, he mentioned the temperature sensor being problematic on those vehicles, which made sense, so I squished the connector ends a bit more to make better contact on the sensor and put some dielectric grease on it.  Didn't help.  I can't seem to find the exact sensor to replace the one I have, rather odd.  Another model may work but I haven't gotten to extricating the old sensor yet.  Need to measure the thread size, I'm a little worried they used something different on the Maximas with the L motor.  I literally go to look it up in my computer and it says it doesn't exist, which is crap, because it's obviously there.

 

The only other things I can think of is the air temp sensor in the airflow meter and the matchbox dizzy.  The airflow meter should get cool fairly quickly though, especially with the K&N filter.  The matchbox heating up is certainly a possibility, but usually when they fail, they fail, they don't return to running fine after cooldown.

 

Any other thoughts?  By the way, no cat and freeflowing exhaust just put on.  Other than that and opening up the airbox a bit, she's a bone stock L24.

[HRH]

Found this interesting thread on this very problem!  It's L28, but basically the same thing minus the displacement.  Think I'll be digging into the AFM a bit.  Might just replace it and adjust the rebuilt one for good measure.

 

http://www.classiczcars.com/forums/help-me/48743-need-help-77-280z-hot-start-issue.html

[datzenmike]

Maybe add a really good ground from the block to the body?

[flatcat19]

AF meter. 

 

I just went and looked at a Maxima here in town last week. 1983. 

Ran great for 5 minutes. Once warm, garbage. 

 

MAF would make a huge banging sound from that little flapper inside when it would have it's "hiccup."

 

 

http://kpr.craigslist.org/cto/4386152562.html

I was actually thinking about buying the thing. It was a beautiful car. Perfect. Great shape. 

It's running issues kept me away. If I was in the market for a project-this would be the one. 

 

Find a carbed manifold, forget the headaches. 

[HRH]

I saw that Maxima.  I'm happy with my ugly one as it runs pretty well minus a few things, but the body is definitely nicer on that one.  Almost debating buying it to have a second! :D  I'm actually really digging the 810.

[flatcat19]

I saw that Maxima.  I'm happy with my ugly one as it runs pretty well minus a few things, but the body is definitely nicer on that one.  Almost debating buying it to have a second! :D  I'm actually really digging the 810.

 

Do it! The whole car is legit. So clean. And the price is right.