4g idle hunting issue

[Drax]

i have yet another hunting issue first time it was a faulty fiav, second time it was a leaky inlet gasket and now its back seems like its something else.

ive done:
-checked fiav by swapping with two others
-checked, cleaned and swapped iacv
-checked for vac leaks (found one small one in a coolant pipe but sorted that)
-swapped tb for known good one
-cleaned egr valve
-drained and refilled coolant and opened bleed valve until fans kicked in (yo)

im convinced its an air lock in the coolant because, as shown in the video below, even after draining it (via the radiator and removing the rear lower coolant hose as i cant seem to get to the proper rear drain bolt thingy ) it still comes out really full of air bubbles.

http://vid218.photobucket.com/albums/cc ... wgw1hl.mp4

plus i suspect its making my engine sound rough on idle

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

its usually something stupid ive done, like not drained the coolant right..... urgh... so all suggestions welcome

[NafemanNathan]

Have you stuck your thumb over the FITV hole in the throttle body?

When you're bleeding the coolant, raise the front end of the car and make a reservoir up out of an old pop bottle with electrical tape around the neck. Then jam it in the neck of the radiator. Then bind the join with electrical tape to insure it doesn't leak or fall out. Forget the bleed nipple for a bit and just watch the bubbles come up into the inverted bottle. The additional height from the reservoir will help force the air out from wherever it's trapped.

[Drax]

Have you stuck your thumb over the FITV hole in the throttle body?

yep, its not the fiav or iacv

When you're bleeding the coolant, raise the front end of the car and make a reservoir up out of an old pop bottle with electrical tape around the neck. Then jam it in the neck of the radiator. Then bind the join with electrical tape to insure it doesn't leak or fall out. Forget the bleed nipple for a bit and just watch the bubbles come up into the inverted bottle. The additional height from the reservoir will help force the air out from wherever it's trapped.

so, the "neck" of the rad is where you top it up?
so i put the bottle in for both bleeding the rad AND once topped up again and the car started ready to go up in temp until the fans kick in? or just for bleeding?
@NafemanNathan

[NafemanNathan]

so, the "neck" of the rad is where you top it up?

Yep

so i put the bottle in for both bleeding the rad AND once topped up again and the car started ready to go up in temp until the fans kick in? or just for bleeding?

For filling and then run the car with it still fitted for the fan to kick in twice. You obviously don't want to finish with the reservoir still full as you'll need to remove it again afterwards, so after fitting the reservoir with the car parked with it's nose slightly raised...

Before running the car just fill the rad up to the bottom of the rad neck.

Then start the car. Chances are the coolant level will drop immediately, so top it back up.

Once the car's running give both rad hoses a good squeeze to get rid of any trapped air.

Then you can also release the bleed valve on the thermostat housing to relieve any air that still might be there. Hopefully there shouldn't be any.

Then allow the car to run up to temp, keeping an eye on the rad level. If ever it drops below the bottom of the rad neck, top it back up. Also squeeze the rad hoses from time to time.

When the car is up to temp the chances are the reservoir will start back filling. This is ok, it should go back down when the fans kick in.

Once the fans have kicked in twice and you've followed everything above turn the car off. Hopefully once the car has cooled the coolant level should remain where you want it, right at the base of the rad neck.

Then fill your overflow up to halfway between max and min and you should be done.

[judderod]

Have you set the idle speed properly? It's in the service manual I think you have to disconnect the IACV.

Idle in that vid sounds a bit rough. Have you checked the plugs?

[Merlin]

What tuning do you have? If you have the Hondata S300 you can calibrate the TPS. When my TPS setting were a little out I did get a very small "bouncing" effect.

[Drax]

tried all what you said @NafemanNathan but no differance even the bottle started melting due to the coolant temp in the rad

Have you set the idle speed properly? It's in the service manual I think you have to disconnect the IACV.

Idle in that vid sounds a bit rough. Have you checked the plugs?

the idle speed is set by the Hondata, ive never done any manual setting as most people say stick with the factory default. I thought exactly the same about the rough idle though, and the first thing i checked was the plugs. all seemed ok except a little white meaning it maybe running lean, which is not usually the case for my lude as its known to run pretty rich

What tuning do you have? If you have the Hondata S300 you can calibrate the TPS. When my TPS setting were a little out I did get a very small "bouncing" effect.

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.

ive also swapped the fuel filter today (arse of a job! ) as it was overdue and just in case the idle was bad fueling.

Im going to drop the car off at a mates garage sunday eve so he can do a proper job of the coolant and check underneath in case he can see anything im missing, appreciate all the input so far guys

[Drax]

got the lude back yesterday from the mechanics and after several weeks he's had no luck. checked a lot of stuff ive already done but then also properly flushed the coolant, checked (and swapped some) vac hoses, gaskets etc. checked the valve clearances and timing too.

its also beginning to run pretty rough, and last I checked the spark plugs it was running lean which is very unusual for my car. im going to swap the main relay, dizzy for the spare and check the ecu wiring in case something has been knocked out of place. it could be a blocked injector but they were cleaned around 2 years ago.

any other ideas, throw them at me

[NafemanNathan]

any other ideas, throw them at me

Yeah, drop your smurf in there already

[Drax]

any other ideas, throw them at me

Yeah, drop your smurf in there already

that's the plan if all else fails .... well, that's the plan anyway damn soon. cross finger this sunday nick can pop over and help me finish the cam timing and its old engine out time.

id rather diag the problem before the new one goes in just in case its not block/inlet related, then ill just have running issues IF the new block runs.

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