4AGZE cold & warm idling problems **EDITTED**

[aesc]

Hi,

Ok well this morning I removed my oil catch tank, so to do this I had to unbolt the intake plenum part off the throttle body to move the elbow off around so I could connect back the original rocker cover/plenum hose. Fine did that, put it back on etc

Started the car up from cold and it would hardly idle, however I drove off and it was fine until it warmed up with no issues with performance

However now at warm idle it revs around 1100-1250rpm, when usually idles around 900rpm. I thought Id check the faults codes so bridged E1 and TE1 however no codes showed BUT the idle did not drop down to 500 rpm like it always has.

Can anyone tell me the problem? All the vac hoses are connected and there doesnt seem to be any vac leaks.

EDIT: Also tried pulling the efi fuse and disconnecting the battery to no avail

EDIT #2 - see down page for summary

Thanks

[CAMB01]

Sounds like you have an air leak.
I know you said you dont think you do, but it sounds like you do

[soopachargen]

good luck on finding your airleak if you have one, just be thankful you havent swapped all the hoses etc like i have. my air leak from my sc14 conversion is a constant battle, i have about 17inHG at idle and it pulses like a rotor when its left to idle.

[Caveman]

good luck on finding your airleak if you have one, just be thankful you havent swapped all the hoses etc like i have. my air leak from my sc14 conversion is a constant battle, i have about 17inHG at idle and it pulses like a rotor when its left to idle.

To you have your rotary solinoid (no joke) wired up properly?

aesc: Definatly sounds like a air leak. An alternative fix is remove all the air bypass valves, this is what ive done. Always starts first time and runs sweet + no hassels

[Vertigo]

can you use soapy water on vacuum hoses to find leaks? methinks it wouldnt work?

[soopachargen]

To you have your rotary solinoid (no joke) wired up properly?

Um... where do i find that..?? i havent changed any wiring but that doesnt mean the guy who put the motor in didnt cock it up.

[gepsk8]

nah, brake clean the best spray it in the spot where u think the airleak is if the car will rev up more ur in the right area,

[aesc]

Ok cheers for the replies. I originally thought it mightve been an air leak, so I sprayed CRC around the throttle body area but it didnt show anything up.

The warm idle seems to be OK now However when I started it this morning it wouldnt idle on its own at all. Would start, but revs would drop really low and then die straight away. Its like there is no fast cold idle anymore. However once I drove it down the road it would idle although at quite low revs (750rpm) when it would usually be around the 1500rpm mark.

Maybe its leaking air around where the plenum connects onto the throttle body? I didnt reaplace the gasket, just unbolted it, removed it (plenum) and bolted it back on.

But this wouldnt explain why the revs wont drop when bridging E1 and TE1 though does it? I mean the revs dont vary at allwhen doing it

[Caveman]

Have you put the water hoses back on the throttle body? Or is the line from the cold idle valve going to the intake or is it blocked? Maybe you havnt pluged in the two air bypass valves which go between the cold start valve and the intake.

[aesc]

Yeah all hoses are where they should be. I didnt disconnect any hoses or anything before it started doing it, just unbolted the plenum enough to lift it up so I could swing that brass elbow around, then put it back on. This is why I'm so confused by it because I didnt disconnect or remove anything. Shouldnt be blocked either, if it is its a big coincidence!

[aesc]

Bump

A summary:

- Doesnt seem to be any fast cold idle anymore - idles around 700rpm when cold (if it doesnt stall)

- Warm idle is back at around 1100-1200rpm.

- When checking fault codes the idle does not drop down to around 500rpm like it used to. The revs at idle do not change when doing this, and I'm not getting any codes.

I have checked for disconnected vac/water lines and everything is intact. Sprayed CRC around the throttle body area to spot air leaks but nothing. I have found that even if there is a vac leak around the throttle body it doesnt effect idle speed.

Even swapped the cold start switch over last night with a spare I have but this didnt change anything.

Any more ideas?

[CAMB01]

Try changing your cold start injector or at least checking it

[Caveman]

Just take the whole damn thing apart and do it properly Cant be too hard to find, its just pipes and abvs. Maybe you've got a crappy gasket, could be anything from what you've posted so my suggestion is get in there and get grease on your hands.