Vs v8 idle problem

[eko]

It probably had no idle issues because his ECU had been tuned.

Ive got his ecu aswell would i be able to put it on just to start it see how it idles woukd the auto ecu crank over mine as mine is manual

 

[Nut Kracker]

Was yours causing the idle to drop and raise by couple hundred rpms every 10 secs or so on idle..the guy i got it off said there was no idle issues when it was in his vn could it be because the dizzy timing etc was adjusted to run for a auto and now its running a manual ecu and gearbox its going out of whack ??

The timing between an auto and manual should be the same. It's the engine that that has to be timed, not the gearbox.
If I lower my idle to factory rpm, it does hunt.
This would be because the ecu would have been tuned to a higher rpm setting.
Try advancing the timing a little and also the rpm. Do both of these in the diagnostic mode,
by bridging pins 5 and 6 of the OBD plug. (Advancing the timing will bring the revs up, so you may not need to bring up the idle much.)
If that doesn't work for you, you would probably have to get the ecu tuned.

It probably had no idle issues because his ECU had been tuned.

Correct.....

 

[Brisbarnz]

righto, warm car up, turnoff car, put jumper lead in diag plug, put ignition on, after 30sec you can now remove iac valve elec plug, start car, bit of throttle if it's hard to start and return throttle to closed.

(This next bit made all the difference to my hunting prob.)

Allow car to idle/hunt for 2 min!!

(At 2 min mark my hunting went all smooth and normal)

Now adjust idle to 500-550.
Turn off car an re connect iac plug. Remove diag plug jumper. Start car, bring revs to 3G to reset iac valve.

You should now have a smoother running engine.

I had hunting probs with my small cammed 5.0 with both std n tuned computers, following this procedure worked for me.

 

[BottleFedVS]

with the auto computer it may not start if yours is a manual,
as the pcm may be looking for the neutral start safety switch that prevents the auto starting in gear!

 

[eko]

Ok thanx for all the help guys soo i finally had time.to fiddle with it today heres what happen

I disconnected both the tps sensor and iac sensor started the car was idling.good but would.miss on rev i plugged the tps back in and when revving she was all sweet..it was idling like a dream with the tos connected and the iac disconnected but was idling bit high i than connected the iac valve back on and went revs dropped down abit and the idle issue came back...soo im sure its the iac valve seeing the problem came back after i plugged the iac back in what does this mean new sensor or is the valve just sticking needs a clean any help would be great thanks....

 

[Jake145]

Nah man a tune is needed I reakon, but I drive my supercharged v6 around with it unplugged cause I have the exact same problem but myn was tuned and I bought a new sensor aswell

 

[Jake145]

What I did is waited till the idle was where I wanted it and then I unplugged it and it stays at at the rpm when it was unplugged

 

[eko]

Ohh ok but my issue is indicating that the iac valve isnt operating properly and gettinh stuck am i right??

A tune may help it run better but its not highly modified to need a tune though thats what puzzles me...

Ill try my old throttle body see what happens

 

[BottleFedVS]

try resetting your idle first then if that is not correct I recommend an iac replacement or a tune afterwards.!

 

[eko]

try resetting your idle first then if that is not correct I recommend an iac replacement or a tune afterwards.!

Is that when you rev it to 3000 rpm for 10 seconds to rest it ??