High idle 1.5k-2k and overheating

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ws180
Driver
Posts: 32
Joined: Sat Jun 23, 2012 7:49 pm

High idle 1.5k-2k and overheating

Postby ws180 » Tue Oct 23, 2012 5:59 pm

89 NA6
OK so first off the car was overheating and caused it to split one of the radiator hoses. Decided to give the cooling system an overhaul with a new ASI rad, new sensors, rad hoses, thermostat etc. While i was doing that i took off the TB to give it a clean out.

Now it's all back together, and it's idling very high starting around 1500 and creeping up to 2000. And its still overheating while idling, however i think i have narrowed it down to the fan relay. Fan won't turn on and if it is overheating il'd imagine it is getting to temp. Tested the fan manually and it works so the motor isn't gone, and had just replaced the thermoswitch sensor. Now when bridging the two points in the diagnostic box i can hear the relay clicking but the fan isn't turning on, so does that mean the relay needs to be replaced? I thought i wouldn't be able to hear it click if it needs to be replaced is all?

Now with the idle, i may have been an idiot and loosened the TPS when cleaning the TB. and i don't know how to set it, so would this be why it is idling high?

Thanks for any help

ws180
Driver
Posts: 32
Joined: Sat Jun 23, 2012 7:49 pm

Re: High idle 1.5k-2k and overheating

Postby ws180 » Tue Oct 23, 2012 7:01 pm

alright, so used the LA10 relay from the horn and tested the two out. Fan one was toast, so just using the horn one for now and the fan turns itself on so all sorted with that.

Idle on the other hand, idn. Idle screw is down as much as it can so i can only adjust it up. And when trying to bridge the two points in the diagnostic box nothing seems to happen

ralt
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Re: High idle 1.5k-2k and overheating

Postby ralt » Wed Oct 24, 2012 9:29 am

Hi.
When you cleaned the throttle body did you clean of the sealer on the butterfly. If you did the car will idle higher as there is no sealer which stops air getting past the edge of the butterfly. Once you seal it idle will be fine.

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hks_kansei
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Re: High idle 1.5k-2k and overheating

Postby hks_kansei » Wed Oct 24, 2012 10:25 am

As per Ralt, I think there's a very thin seal around the edge of the butterfly.

It's not just silicone or something, it's some form of special paint. Mr Pham has used it before on his quad throttle system, maybe ask him?



Other option is to look around and see if there are any hoses disconnected/split causing a vaccuum leak.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

93_Clubman
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Re: High idle 1.5k-2k and overheating

Postby 93_Clubman » Wed Oct 24, 2012 12:08 pm

Yeah, sounds like cleaning the TB has effected the brown coating around the TB bore at the butterfly.

Following what you've done, it's worth disconnecting the battery & pumping the brakes a few times to clear the ECU codes etc.

ws180
Driver
Posts: 32
Joined: Sat Jun 23, 2012 7:49 pm

Re: High idle 1.5k-2k and overheating

Postby ws180 » Wed Oct 24, 2012 6:34 pm

ah ffs, thanks guys. Most probs did clean it off cause that makes sense, hopefully that fixes it up but. Thanks again


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