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N/A ideling high and hesitating


Guest loughman

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Guest loughman

Hidi Folks,

 

In a bit of a pickle again, any help will be most appreciated.

 

I recently gave the oul girl (1995 3.0l N/A) a bit of a going over and tune her up for a few outings in the good weather.

 

I, a, changed spark plugs (NGK Platinum Tips)

b, changed rocker cover gaskets (removing throttle body as far back as manifold)

c, changed oil and filter

d, changed coolant

 

Since ive done the work the car is idling up and down between 1500 and 2000 rpm, which would suggest to me too much air intake. Previously it was a steady 1000 rpm.The car is also hesitating under power, in short she's running like a dog.

 

The car runs a greddy/airnix induction kit. Inspecting the air filter i noticed that part of the underside of it was missing, i assume it has desintegrated. I have ordered a new one. Unfortunately it is coming from the U.S and may take a few weeks in coming.

 

From experience do you feel the filter is the more likely culprit or could it be something to do with the work listed above or indeed a mixture of both.

 

Any help guys would be greatly appreciated as i would like to get her up and running asap with this good weather which in this country you can be guaranteed wont last too long.

 

thanks.

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what part of the throttle body did you remove? did you just undo the six bolts on the y pipe and lift out of the way or did you split it more than perhaps you needed to? Of the work done this is the area i'd focus on. Did you pop all the little vacuum pipes back on? there is a fiddly one sort of down under and in between the two Y pipe bits of Ali. I'm not clued up enough to know what the outcomes are of each pipe or even if they can cause your issue but if it was fine before it'll be something you've done or not done and these little pipes are easy to miss.

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Guest loughman
Na's can have an extremely high idle when cold.... not sure about the hesitation.

 

Cheers buddy.

 

Your correct she always ideled high on starting (round 1300 rpm) but she always settled down to a level 1000rpm after a short while.

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Guest loughman

Cheers buddy. I will get a good duke at her tonight and tomorrow. All this good weather and no supra to let fly is near enough to put a man off in the head lol

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Guest loughman
what part of the throttle body did you remove? did you just undo the six bolts on the y pipe and lift out of the way or did you split it more than perhaps you needed to? Of the work done this is the area i'd focus on. Did you pop all the little vacuum pipes back on? there is a fiddly one sort of down under and in between the two Y pipe bits of Ali. I'm not clued up enough to know what the outcomes are of each pipe or even if they can cause your issue but if it was fine before it'll be something you've done or not done and these little pipes are easy to miss.

 

Cheers buddy. I will get a good duke at her tonight and tomorrow. All this good weather and no supra to let fly is near enough to put a man off in the head lol

 

- - - Updated - - -

 

Check you have put all the vac pipes back in properly, there are a few that aren't obvious on first inspection on the right of the throttle body.

 

Will do thanks for the help much appreciated

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The throttle position sensor thing is the one thing that's always caused my idling to be all over the place after removing throttle body etc.

 

If you removed it all, including throttle position sensor thing, and didn't make note of its position when refitting, that could well be it.

 

There's also an idle adjuster screw on the throttle cable assembly that I needed to tweak ever so slightly.

 

Have a good search on the forum though as it's been covered relatively recently (possibly in the last 6 months when I last had trouble).

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there are a few possible reasons for that..

no 1 start the car and use a carbulator spray or break cleaner spray and start spraying the whole area you worked on one place at a time..if the engine revs a bit higher or the engine noise change there you have a leakage

no.2.. as above check again all the vaccum pipes you removed that all are in correct place and not broken

no.3 take out the idle valve and clean it very good with carb cleaner..there are instructions online

no.4 you probably messed the calibration of the TPS (throttle position sensor).. again there are instructions online how to calibrate it

no.5 i had the same issues after removing throttle and after of 2-3 days of driving the car was fixxed by its self

 

so do everything above drive the car a couple of days and leave no4 for last

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