Hey

Been chasing this problem for a couple of weeks now and I'm out of ideas. Hoping someone on here might have a solution.

Was having some very hard starts just as it got cold, ended up replacing the battery which has been fine for 2 weeks now. I think this problem is just coincidence but I'll include it for the background story.

It starts fine, but as soon as the initial surge in revs drops it stalls. Its not quite every single time, it seems to start fine when its been parked on an incline with the engine higher. When its on flat ground it stalls 98% of the time. Giving it a bit of gas starts it no problem every time. So its not the end of the world its just super annoying because I know that something isn't quite right.

Now, heres a list of work I've done to it in the last few days -

Replaced battery
Replaced spark plugs
Replaced fuel filter
Reset idle air control
Cleaned MAF sensor

Once it is running its fine, does not stall, idle seems normal. The only other thing wrong with it right now is there is a rattle that directly corresponds to the accelerator pedal being depressed, disappears once the engine has warmed up. Not throwing up any codes either.

Anything spring to mind to check?

Thanks!

Couple of questions:
Do you have a OBD scan tool with the ability to record and recall real-time diagnostic tests like fuel trim behavior?
Second, what procedure did you follow to "reset" the IACV?

Idle Air Volume Learning I should say, using this -

https://forums.nicoclub.com/how-to-ecu- ... 45702.html

After completing the above, idle revs do drop out of specified range, to around 500rpm and it sounds laboured. Once you shift into N, revs sit nicely at around 800. Now if I go back into P, expecting 500, its sits at around 1100.

I have a scanner, I will look at fuel trim behaviour. What specifically should I be looking for?

Thanks!

Since you mentioned a hard start issue, check your fuel pressure regulator and fuel pressure damper. Both are up top near the front and are easy to check. Let the vehicle run for a few minutes then shut it off. Each part has a small rubber vacuum hose connected to it. Pull each one off and if either has fuel in it (it should be bone dry) then that part is bad and needs to be replaced.

I strongly suspect the IACV is failing, and if it's not too late, it will damage your ECM.
When it's that old, replacing it now will save you a lot of headaches and money.
If it's too late and the ECM is damaged, you'll have to send it out for repairs. It's not that expensive, but it's a major inconvenience.

Had the same issue, including stalling sometimes after driving, parking, restarting. Different mechanics had the common ideas/fixes, but what worked for me was simply popping off the intake hose, and cleaning the throttle body with a damp rag. Used a screwdriver to hold open the butterfly valve to clean past that. Issue fixed. Bought some throttle body cleaner and hit it again, just to be sure. The first two trial starts were rough, though, as the engine/ecm reacts to a cleaner combustion, I reckon.