1995 pickup 2.4 wont idle

[Niti QX4]

Thinking about this more, BUT as a carburetor system;

no codes in Mode 5 BUT only above 1000RPM. Assuming not able to get realtime codes at idle as engine would not run.

As a carb system not able to idle - I would look at the idle screws and idle passages, check for vacuum leaks, and confirm the dizzy isn't wandering on timing.

In this case:

1. Check compression and balance across cylinders.

2. Is the choke working correctly and is the idle screw set properly:

https://www.nicoclub.com/archives/ka24d ... -idle.html

https://www.infamousnissan.com/tech-are ... your-ka24e

3. If so, then let's look at fuel delivery at idle speed (or as close to idle as you can). PSI, and then cranking check for flow/volume.

If those are good, then it seems like a vacuum leak might be the issue. Since it won't idle, there is no way to get a vacuum reading, but if you use a smoke test, it might help.

[Niti QX4]

OP, any news?

[xrjoe]

just got a smoke generator, didnt come with smoke liquid??? 12 miles this morning for liquid purchase, ill load the intake to confirm any problem areas, although i usually can trace vacuum leaks with a hook tube quickly, i can reach under intake checking non visible areas listening for leaks. this is more like a multiport injection with throttle body, i have removed idle air screw, port seems fine, the small hole in t.b. for maf sensor also serves idle air, at lower rpms i sprayed start fluid to enrich idle running condition, and it ran alot better, if i confirm no other vacuum leaks, the only other fuel control at idle is ecm

[Niti QX4]

Please keep us updated. Thanks!

[xrjoe]

smoke generator revealed a intake leak i couldnt hear with hose, under side of manifold had the gasket suck into the two center ports, the center bolts gasket holes broke away allowing it to move, you were right niti, thinking it had to be something like that, getting the manifolds loose is a bit of a chore, once assembled and ready to fire, i needed to set idle and timing, seems to run pretty good even with t-chain out one link on cam, its still tight, but will need to be addressed soon, so the list to regain idle includes, replacement of iac valve, tps sensor wouldnt close idle position circuit, intake gasket leak, if this truck was 1 year newer, it would have obd2 diagnostics with alot more information pointing toward repair, being that i mostly work on diesels, these older engines do present a challenge. back in 1977 i bought a '75 vw camper bus with vintage cis injection, when i had a few problems with that, it became carbureted and very dependable. ill get a drive on the pickup today to confirm hopeful success.

[Niti QX4]

Awesome news!! Congratulations on the fix!!

[VStar650CL]

Congratulations on the fix!!

And congratulations on the diagnostic advice. Well done.

[Niti QX4]

Thanks, but it was a team effort. Between all of us, it got solved. Always a good feeling to get something fixed and back on the road!

Great job again OP!!

[xrjoe]

did good cruising and at speed, and yes a great group effort for sure, someone will come across a similar idle issue, and possibly down the road they can benefit from this thread, m next plan is clean the motor, spiffy it up a bit, after all this time it still cleans up, thanks soooo much for the help, forums like nico do help alot when you have a few thinking in your court, and relative car experiences.

[Niti QX4]