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More High Idling trouble


Rob

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There doesn't appear to be any vacuum pressure in that pipe at all, as if it's blocked. Would the vacuum pull the butterfly closed ie is it designed that way? With the engine off, the throttle return spring is sufficient to shut the throttle, and it's quite a strong spring, requiring a final damper.

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Iv got the same problem but the other way round!!

When i first get in the car if it hasnt been driven for a few hours it idles at 2000 but after bout 5minutes it settles down to 400-500.

Problem is cos i got a aftermarket exhaust on my n/a I wake everone up in the village at half 6 in the mornin when i leave home.

can i fix this anyway?

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is there a seperate adjuster for warm idle? i recall collecting my car from Hyper Sports once & it was high idling after i'd got a mile or two down the road. when i went back, he just adjusted something on the throttle cable with a spanner & it was sorted

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Ok, did that, no effect while it was running hot and high revs, but when i switched off and immediately re-started, it idled at normal 700 and dis-connecting the TPS caused the revs to rise.

 

Any diagrams to show the two sensors you mean, and the same for what CW said?

 

Another note, while it was idling high after driving, I watched the throttle lever (the one I can push shut to return revs to normal) and whilst watching, pulled the connector on the Dizzy cap to kill the engine. I could see the throttle lever move slightly to close as the engine died. I'm convinced something is holding the butterfly open but I don't understand how if it's purely a mechanical device connected to a cable.

 

OK so when you disconnect the TPS sensor, it doesn't make a difference to the revs?

This says to me that there's a break somewhere between the TPS sensor and the ECU. Try measuring the TPS voltage at the ECU when it's running normal, and again when it's high idling. If it's different then it's deffo a loose connection somewhere. My money is still on a loose connection at the plug.

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No, when running high disconnecting the TPS made no difference, which I'm assumming is because the throttle is slightly ajar which will negate anything the IAC can do.

 

However when pushed shut and idling at 700, disconnecting the TPS does cause the revs to rise, reconnecting makes them drop again.

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No, when running high disconnecting the TPS made no difference, which I'm assumming is because the throttle is slightly ajar which will negate anything the IAC can do.

 

However when pushed shut and idling at 700, disconnecting the TPS does cause the revs to rise, reconnecting makes them drop again.

 

Yeah it will do. The IAC valve looses it's signal and just parks itself at something like 63% open. If you disconnect the TPS when it's revving high, you're interrupting a signal that's already been interrupted so it doesn't make a difference.

 

I don't think it's the butterfly being slightly open, unless you've adjusted the set screws. Plus if it was revving high, and then the IAC opened it would rev higher as you've let more air in.

 

I found that if I pushed the butterfly shut, it somehow caused the connection to make again, which dropped the revs. I kept thinking it was the little dashpot that somehow causing something strange to happen. It was only by accident that one day I nudged the connector and the revs dropped. So I had it all apart and made sure that there was always going to be a good connection between the plug and socket, and my weird idling went away.

 

The pin out diagrams are on here in the technical section IIRC. If not I'll find them out when I'm home.

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Yep, IAC removed, dismantled and cleaned, and tested.

 

Although jiggling and tapping caused no revs drops, I'll pop the TPS off then, although I read somewhere that one shouldn't remove it at all, is that true?

 

When I removed a vac pipe from the Vac sensor on the bulkhead it killed the engine for gen info.

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It's probably engine vacuum going through that hose in the pictures attached above that is nerfing the throttle open a bit for some reason (NA's are not my forte). Try removing the hose and temporarily blocking the feed barb on the throttle, and see if it still drops the throttle shut when you kill the engine.

 

-Ian

 

Had no effect, I could still see the throttle close the last few mm when the ignition was switched off.

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Took the TPS off, tapped it, fiddled about, cleaned all the contacts, put it back on. No real difference, although driving to work today I noticed the car holds back more on "overrun"

 

Whilst stuck in a jam for 15 minutes it was idling at 1100, so I switched off and restarted and it idled at 700, but when I crept forward a bit, say at no more than 10mph it then idled at 900 and after going a bit faster idled back at 1100-1200.

 

Re-checked error codes tonight and got a 13.

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Rob, sorry for the delay will try and post something up tomorrow (definitely by wednesday)............

 

error code 13

 

reason -

No NE signal to ecu for 0.1 sec or more at 1000rpm or more

OR

NE signal does not pulse 12 times to ecu during interval between G1 and G2

 

NE G1 and G2 are the three pickup coils in the distributor.......G1 and G2 inform the ECU of crankshaft angle NE informs the ECU of "ENGINE SPEED"

 

code 13 ;- This code indicates that a momentary interuption of the G, NE signal from the distributor to the ecu has occurred,but that it has returned to normal . Note that although this problem may not necessarily appear at the time of inspection, it cannot be ignored because this diagnostic trouble code is output, indicating that there is or was a malfunction in the G, NE signal circuit: this malfunction is usually a "loose connector".

The distributor connector and the NE terminal of the ecu connector must therefore be checked for the following

 

1) Loose connector

2) Dirty connector terminals

3) Loose connector terminals

 

 

Straight from the manual - just highlighted possible important bits.

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Rob are you refering to the pipe in the diagrams attached? if so these attachments may be some help........

 

 

By the way i've just seen this again and am thinking that maybe a whole throttle body may be a better way of sorting this............you could always compare the two to find out what part is faulty on yours.....(tbh i'd rather send you the whole thing than swear and curse at removing the sensors!)

 

Sorry i've been a bit slack, I'll fish the whole thing out tomorrow.

 

Received it today, thanks very much.

Is there any way you could have packaged it to make it look MORE like a child's torso wrapped in a plastic sack? My colleagues think I'm some sort of mail-order paedo-killer now.

 

I'll swap the whole thing over this weekend and give it a run, I reckon if the same symptoms occur, then it must be something in the vacuum pipes. If it's all fine I'll then try my own TB back and swap the IAC, TPS, one at a time to pinpoint the item.

 

I notice your TPS is in a different rotation to mine, was it all running sweet with this on do you know? Although I suppose on assembly Toyota adjust each car to account for the vagaries of manufacture.

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Received it today, thanks very much.

Is there any way you could have packaged it to make it look MORE like a child's torso wrapped in a plastic sack? My colleagues think I'm some sort of mail-order paedo-killer now.

 

I notice your TPS is in a different rotation to mine, was it all running sweet with this on do you know? Although I suppose on assembly Toyota adjust each car to account for the vagaries of manufacture.

 

I thought giant jelly baby........'you' thought childs torso! :D

 

Unfortunately i can't confirm it was all a ok i'm afraid as its off a 2nd hand engine i brought..........DAMOA may be able to confirm......it was sold to me as a 'ok'..........

 

There was some oily grime in the runners etc and i cleaned it up a fair bit inside, but you may wish to have a good look before installing...........

 

Good luck with it, hope it sorts it gives you a few more things to try at least...........

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Right OK, sweet jesus this is doing my head in.

 

With scooters TB on, my car runs perfect, albeit idling at 600 when hot as opposed to 700.

I swapped the IACs which gave no effect meaning my IAC is perfect. It must be the TPS.

Scooters gives a reading of 20 odd Ohms across the 4 and 3 pins, mine gives 0.8 and mine is impossible to set up, it jsut deflects to no circuit, then using both 0.16in and 0.24in feelers under teh throttle stop gives no circuit either way.

 

Anyone agree it's fubar'd?

How much are they, are do you want to sell yours Scooter?

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I have some wheels i won on ebay...........'Sunderland' is where the buyer is.........

 

Ideally i'd pick them up but it is a looooooooong way from down here.......I know a courier is approx £10-12 per wheel but its the whole £300+£50 to courier all up front via paypal to the seller. Probably just being paranoid but i'd rather you got them and i arranged a courier from you to me!

 

Its no biggy just if you were that way etc........I'll try and find out where exactly they are, as he's away until this Friday anyway..........

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OK, now this is interesting. All seemed fine with Scooters TB when I was around town on the weekend, but this mornings drive into work has resulted in the car sitting in the work car park idling at 1100 again.:search: :search:

 

Turning off and restarting, it idles at 700.

 

Does this mean the TB and all it's sensors are totally irrelevant?

CW mentioned the water temp sensor but where is this on the NA? and how do I test it?

 

Again, why does actually rolling the car on the road cause the problem when high revving whilst stationary does not?

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