Why dont I have smooth idle?

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sticky nicky
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Location: Perth WA

Why dont I have smooth idle?

Postby sticky nicky » Thu Jan 09, 2014 6:52 pm

Hi guys,

Since putting in a new adaptronic ECU, changing back to 4 injectors instead of 5, and re-tuning, my 1989 turbo MX5 hasnt been idleing smoothly. I will start it up and without my foot on the accelorator it will go straight up to 2000rpm and then slowly drop to 1000. Then whilst driving, if I slow to go around a corner and change down, the revs go up! The other day I drove it to the shop, parked up for 15 mins and when restarted it shot up to 3000rpm without me touching the accelorator.

Yesterday I took out my factory air flow metre as the tuner said it wasnt needed anymore and put in a piece of stainless steel pipe in its place. This seems to have improved the rev problem a fair bit but its still not right, still reving randomly, but not as often.

Im taking it back to the tuner on Monday but he doesnt seem to know what the problem would be so is going to have a look at it.

Any suggestions? :?

Thanks

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A.Chen89
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Re: Why dont I have smooth idle?

Postby A.Chen89 » Thu Jan 09, 2014 7:00 pm

You need to tune the idle control

Amount of fuel at idle, load compensation for AC/power steer, idle at hot/cold (fuel enrichment when cold), idle control valve etc.

Tuner should be able to sort it out.

sticky nicky
Fast Driver
Posts: 255
Joined: Thu Sep 09, 2010 10:46 am
Vehicle: NA6 - Turbo
Location: Perth WA

Re: Why dont I have smooth idle?

Postby sticky nicky » Fri Jan 10, 2014 6:16 pm

Thanks A.Chen89, I would have hoped the tuner has already done that but I will check with him :)

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Okibi
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Re: Why dont I have smooth idle?

Postby Okibi » Fri Jan 10, 2014 11:30 pm

Who's doing the tune?
If you had access to a car like this, would you take it back right away? Neither would I.

sticky nicky
Fast Driver
Posts: 255
Joined: Thu Sep 09, 2010 10:46 am
Vehicle: NA6 - Turbo
Location: Perth WA

Re: Why dont I have smooth idle?

Postby sticky nicky » Sun Jan 12, 2014 12:37 pm

Hyperdrive

sticky nicky
Fast Driver
Posts: 255
Joined: Thu Sep 09, 2010 10:46 am
Vehicle: NA6 - Turbo
Location: Perth WA

Re: Why dont I have smooth idle?

Postby sticky nicky » Thu Jan 16, 2014 7:13 pm

Well, took it back to Hyperdrive, Andrew did some adjustments to the ECU and its running a LOT smoother now :D

mr bender
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Re: Why dont I have smooth idle?

Postby mr bender » Thu Jan 16, 2014 7:25 pm

cool

ja9
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Re: Why dont I have smooth idle?

Postby ja9 » Fri Jan 17, 2014 8:01 pm

Just so the rest of us learn something from your issue do you know wht the tuner did to improve things? Short post cranking, perhaps?
UNDERSTEER is when you hit the wall with the front of the car. OVERSTEER is when you hit the wall with the rear of the car.

sticky nicky
Fast Driver
Posts: 255
Joined: Thu Sep 09, 2010 10:46 am
Vehicle: NA6 - Turbo
Location: Perth WA

Re: Why dont I have smooth idle?

Postby sticky nicky » Sat Jan 18, 2014 2:19 pm

Sorry Ja9 I didn't ask, not very car savvy so I probably wouldn't have understood the answer anyway :-/


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