Help wanyed with blue top running issue

[Me_19588]

Hi i have a factory rwd blue top in my ke25, it runs but not well

Has an idle problem where it idles at about 3-4 grand, idle screw is as far down as it goes.

It also drives horribley to 5 grand where it seems to take off quite nicely.

In the throttle body there is that air bypass hole, if you put your finger of said hole the idle drops down to around 800 -1000 where it should be.

Just wanting to know if any ones knows how to correct this problem, i have changed throttle bodies made no difference.

Thanks for any help

[Jazza]

In the throttle body there is that air bypass hole, if you put your finger of said hole the idle drops down to around 800 -1000 where it should be.

Tried covering it over and driving with it? If it drops the revs to where they should be, maybe its the problem?

[Caveman]

The hole could be the idle screw adjuster or the cold start bypass/ps bypass.

The hole for the screw adjuster is on the side and the cold start/ps idle up is on the bottom.

if the car has ps it sounds like you might have a split in one of the lines going to the steering rack or your cold start valve is busted.

I just took off all that crap and sealed it with a plate and gasket.

Maybe just try take the tb off and spray it with a little tb cleaner?

[Me_19588]

no power steering or any thing, all lines lines blocked up, have had 3 different idle valves on it, results all the same.

[Caveman]

Are you running a fwd or rwd tb?

The I think the breather hole and idle screw holes are in different locations on the 2, someone will know more about this

[2LTR Rona]

Is you tb set up looking like this? including the vaccum line running from the top to under neath?

[ee904age]

The engine wasn't out of a crashed FWD by any chance was it?
I had a very similar problem with mine, it turned out to be a bent dizzy shaft. It had chipped a tooth off the pickup wheel and ran like crap at low revs and would idle at bout 3000rpm

[jondee86]

Does the idle speed drop at all from cold to hot ?? It should do
if the cold start thermo idle-up valve is working...

Cheers... jondee86

[Me_19588]

factory rwd throttle body, but now have an mr2 one on,

my vacum line is running from the bottom piece straight across to that vacum diaphrame buy the throttle cable

[Jebus]

K, the vacuum hoses on top are not necessary at all, block them too. Im assuming your using the bottom half of the throttle body you got off me. For FWD T/B on RWD manifold you dont need any vacuum hoses, just the 2 water. and theres nothing else you have to block other than the ones that are blocked on the piece I sent you, and the 2 on top.

The running shit below 5K is the TVIS actuator, TVIS is not closing. Check the hoses and plugs.

The high idle is either an air leak, or there is a throttle stop at the bottom of your throttle which someone has $&#$% with and isnt allowing the throttle body to close fully.

[Maxwedge]

I had a similar problem on my FXGT. I changed throttle bodies as well, changed cold start valve as well with still no change. I read somewhere that because the cold start valve is positioned relatively high in relation to the radiator filling point, sometimes if you dont fill and bleed your cooling system correctly you can get an air lock and the warming water may not reach the cold start valve in full proportion and may not activate the valve. I filled the block by removing the top radiator hose at the radiator and filling from here. Once I did that the engine speed dropped down and I have never had a problem since.

[l1ttle_d3vil]

if its been a conversion and wiring modified, check your coil/ignitor wiring and make sure it is getting good connections from ECU to coil etc. don't just check for continuity with a multimeter, actually re-crimp or solder any terminals which have been done and see if it makes any difference.

same goes for the dizzy wiring.

this is ofcourse, if any of these wires have been cut or anything.

[KinLoud]

I just put a foam earplug in the hole you are talking about - this was on my racecar where cold drivability wasn't really a concern.

Ken
Ham
021 408 863