4g idle hunting issue

Post by **Merlin** » Fri Oct 09, 2015 2:43 pm

Drax wrote:id have to check if we have calibrated the TPS during tuning with the Hondata, but ive tried a different tb with a different TPS and it made no differance.

Changing the TPS wont do anything as it is the ECU's measurement of the position of the throttle plate that matters. When you set the TPS on the S300 you are telling the ECU when the plate is closed and when it is fully open.

Post by **NafemanNathan** » Fri Oct 09, 2015 2:43 pm

Drax wrote:could a faulty coolant temp sensor cause this kind of issue?

Yes. That was the source of my surging issue on the 3rd gen. 4th gens use the same temp sensor.

Post by **Drax** » Fri Oct 09, 2015 2:46 pm

NafemanNathan wrote:
Drax wrote:could a faulty coolant temp sensor cause this kind of issue?
Yes. That was the source of my surging issue on the 3rd gen. 4th gens use the same temp sensor.

new replacement is on the cards methinks, cheers Nath!

Post by **NafemanNathan** » Fri Oct 09, 2015 2:47 pm

The orange circled one here to be sure...

Sender, not a sensor

Post by **Merlin** » Fri Oct 09, 2015 2:51 pm

The orange one is only for the temp gauge. It is not ECU related.

Drax wrote:http://vid218.photobucket.com/albums/cc ... ezevey.mp4

IS that still the same issue you have?

Post by **Drax** » Fri Oct 09, 2015 3:03 pm

right, so its the coolant sender that could cause the issue, not the coolant sensor?

or shall I just swap both of those

ill have spares of both on my new block and Will's lude that is currently taking up my drive space

Post by **Drax** » Fri Oct 09, 2015 3:04 pm

Merlin wrote:
Drax wrote:http://vid218.photobucket.com/albums/cc ... ezevey.mp4
IS that still the same issue you have?

yes, although now sounds a tad worse

Post by **NafemanNathan** » Fri Oct 09, 2015 3:06 pm

Hmmm... replacing mine certainly cured my 3rd gen. It used to run too rich. It would start fine when cold, but after it was warmed up if you turned it off and tried to restart it it wouldn't and the spark plugs were always saturated in fuel.

I removed the "sender" and replaced it with one from my 4th gen...

The corroded one on the left was the original 3rd gen one, the one on the right was from my 4th gen, which I cleaned up...

I never had any restarting issues again after that.

I'm just going to go back through my 3rd gen history as I realise that isn't a hunting issue, which I also suffered from

Bare with me.

Post by **Merlin** » Fri Oct 09, 2015 3:13 pm

Swapping the coolant temp sender will not do anything.

TBH the vid does not sound like hunting to me. A bit "put-put-put" but not hunting.

This is what I class as hunting, bouncing of idle from 1-2K.
[youtube]wwm0-tlsNHk[/youtube]

See the start of this vid and see if the idle noise is the same:
[youtube]lNyJpI42Zls[/youtube]

Post by **Drax** » Fri Oct 09, 2015 3:16 pm

ah no, don't be deceived - that video only shows the rough idling before the engine begins to warm up and hunt. ive had multiple hunting issues so I know what it is

sorry, I should have made that clearer Merl