hole in throttle body in front of the butterflies bottom left what is it? picture. idle issue.

[FrazUK]

What is this for? My idle is high but if i block this off with my finger it drops to the right idle RPM. It sits about 1500 RPM otherwise. It then will start jumping about as if it's hunting idle. Switching between holding 1500 and bouncing between 720 and 1500. Car is on Apexi PFC base map.

It was well higher but the TPS was way off so that has brought it down a bit. Tried disconnecting the throttle cable, no change. Open to suggestions. Also cant find a boost leak and it drives fine just idles shit.

 

[Nite_Shayde]

I think that's the passage to the idle control valve, which is probably the cause of your problem. Could try removing it and spraying it liberally with some carb cleaner to see if it helps

 

[FrazUK]

I think that's the passage to the idle control valve, which is probably the cause of your problem. Could try removing it and spraying it liberally with some carb cleaner to see if it helps

Will give that a try many thanks mate.

 

[MKZ7212]

Get a flat head screwdriver and wind the screw in just below the TB just next to the bottom right stud in you pic, from memory you wind in right in then back it out 1 1/12 turns, this will adjust the idle control, presume your TPS is in range now?
What ecu are you using?
Was the idle ok before? Or is it a rebuild?

 

[FrazUK]

I wound it all the way in then back out half a turn. Yeah the TPS is with the ranges now. It's on an Apexi Power FC on base map. The idle was high before on the standard ECU. It seems 'better' on the Apexi but still high and bouncing every now and then as it was on the standard ECU.

 

[Spendyrx]

Sounds like a leak to me!

 

[FrazUK]

Sounds like a leak to me!

Will try having a look again but its a pain in the arse trying to find a leak with vacuum pipes running all over the shop.

 

[MKZ7212]

I wound it all the way in then back out half a turn. Yeah the TPS is with the ranges now. It's on an Apexi Power FC on base map. The idle was high before on the standard ECU. It seems 'better' on the Apexi but still high and bouncing every now and then as it was on the standard ECU.

Have you done the idle learn on the apexi?

 

[Spendyrx]

Actually, thinking about it......do you have a mate who could lend you a throttle? Maybe worth trying another throttle or even looking at where everything lines up on another! Maybe your butterflies are slightly out! Or even your thermo wax!

 

[FrazUK]

Have you done the idle learn on the apexi?

I've done the initialise all data switch off switch on, then when you turn it back on does it go in to it by itself or do i have to do anything? It doesn't give me any indication it's doing it but i did the 10 mins window heater on 10 mins ac on for 10 mins.

 

[FrazUK]

Actually, thinking about it......do you have a mate who could lend you a throttle? Maybe worth trying another throttle or even looking at where everything lines up on another! Maybe your butterflies are slightly out! Or even your thermo wax!

Unfortunately not mate. I did have a look at the butterflies but beyond that and other obvious gaps i can't see anythinf suggesting they're not closing. What is the thermo wax?

 

[Spendyrx]

You just leave it do it's thing. You kinda hear the hunting stop after a few mins when it's doing idle learn!
Thermo wax is on the side.....one sec.....

 

[Spendyrx]

In the yellow! That opens as the throttle warms and adjusts your idle speed/ acts like a choke! It won't make your car hunt but it will make it idle high if not set correctly. When the car is warmed up, just pull on it to see if there's any change in idle speed. If not then leave it do some reading on it all, it's a bit of head work but may help with some issues!

 

[FrazUK]

In the yellow! That opens as the throttle warms and adjusts your idle speed/ acts like a choke! It won't make your car hunt but it will make it idle high if not set correctly. When the car is warmed up, just pull on it to see if there's any change in idle speed. If not then leave it do some reading on it all, it's a bit of head work but may help with some issues!

View attachment 12588

Will give that a try tomorrow. Dont think the neighbours would be happy firing it up at this time.

 

[bash]

I'd turn the screw all the way in then back out a full turn. Seemed for me to be different than the prescribed 1/2 a turn thing.
Hunting i'd check the cables on the connectors which go to the PFC; if you have a loose wire you'll find it'll hunt and FDOC about then seemingly fix itself. This happened with mine. Just give the power fc ecu box a wiggle whilst it's running and see if the hunting appears and disappears.

It could also be the wax rod on the back of the inlet as people have been saying, make sure when the car warms out that the little arm extends out. you should see this visually happen and then the revs drop. Watch on the hand controller and when you get to like 65 deg C it should have opened IIRC.

I'd also pull the ICV off the back of the inlet and clean it out with carb cleaner. It could be scummed up with shit. If you take the UIM off then check vacuum hoses for perishing / leaks.

 

[FrazUK]

I'd turn the screw all the way in then back out a full turn. Seemed for me to be different than the prescribed 1/2 a turn thing.
Hunting i'd check the cables on the connectors which go to the PFC; if you have a loose wire you'll find it'll hunt and FDOC about then seemingly fix itself. This happened with mine. Just give the power fc ecu box a wiggle whilst it's running and see if the hunting appears and disappears.

It could also be the wax rod on the back of the inlet as people have been saying, make sure when the car warms out that the little arm extends out. you should see this visually happen and then the revs drop. Watch on the hand controller and when you get to like 65 deg C it should have opened IIRC.

I'd also pull the ICV off the back of the inlet and clean it out with carb cleaner. It could be scummed up with shit. If you taker the UIM off then check vacuum hoses for perishing / leaks.

Will do that tomorrow then. Cheers mate

 

[FrazUK]

Ok so the thermal wax comes out as it heats up. The ICV I've cleaned. the issue isn't as bad but still exists.

As the car warms up the revs climb, the revs bouncing i can stop by adjusting the idle screw on the top left the holds the butterflies open but I can't get it below 2000 rpm without it starting to bounce again. On the commander when it starts bouncing it shows injector duty going 7% 0% 7% 0%.

I can lower the revs with the butterfly adjuster down to 800rpm but, when restarting it it idles at 400rpm and struggles to get going.

I'm starting to think the only way to solve this is have it mapped. I've sprayed as many of the vacuum lines as I can see so other than having it pressure checked and smoke tested.

 

[Ceylon]

My car did this when I had a solenoid failure in the rack. I had to use the throttle to keep it running on a hot start until I swapped the faulty solenoid out.

 

[FrazUK]

The rack? As in under the UIM?

 

[Ceylon]

Yep .