# whats the problem?
**URL:** https://forums.speedlife.net/t/whats-the-problem/123879
**Category:** SON240sx Automotive
**Created:** [April 24, 2009, 8:57pm UTC](https://forums.speedlife.net/t/whats-the-problem/123879 "2009-04-24T20:57:13Z")
**Posts on this page:** 13
**Page:** 1
### Author:  [@89\_coupe](https://forums.speedlife.net/u/89_coupe)
#### Post date: [April 24, 2009, 8:57pm UTC](https://forums.speedlife.net/t/whats-the-problem/123879/1 "2009-04-24T20:57:13Z")
ok so heres the deal. i bought a 1989 240sx 5speed coupe with 118 000km. i bought it off a guy on a farm. he says it has been sitting for a long time. it starts fine and all is great but i have a weird idle. it will be sitting at 1500rpm then it will jump to around 2000rpm then drop back to around 1500rpm and it repeats every like 5 sec. could this be a bad idle air control valve or is it just because it has been sitting for so long and needs a tune up?
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### Author:  [@sidewayz240](https://forums.speedlife.net/u/sidewayz240)
#### Post date: [April 24, 2009, 9:53pm UTC](https://forums.speedlife.net/t/whats-the-problem/123879/2 "2009-04-24T21:53:36Z")
Well it needs a tune up either way, so do that first.
Could be a vacuum leak also.
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### Author:  [@IRo](https://forums.speedlife.net/u/IRo)
#### Post date: [April 25, 2009, 12:16am UTC](https://forums.speedlife.net/t/whats-the-problem/123879/3 "2009-04-25T00:16:04Z")
Check the vac lines for cracks ect.
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### Author:  [@89\_coupe](https://forums.speedlife.net/u/89_coupe)
#### Post date: [April 25, 2009, 5:10am UTC](https://forums.speedlife.net/t/whats-the-problem/123879/4 "2009-04-25T05:10:30Z")
ok thanks. some of the hoses did look like they were starting to crack. ill check that out.
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### Author:  [@87s15lt1](https://forums.speedlife.net/u/87s15lt1)
#### Post date: [April 25, 2009, 5:43am UTC](https://forums.speedlife.net/t/whats-the-problem/123879/5 "2009-04-25T05:43:01Z")
If the car sat for “X” amount of years. Trace everything. Every hose, wire…everything. Let it run and get nice and hot. Oil change, then another. FULL tune-up. FRESH gas is a major factor as well. Then diagnose electrical engine components. Do the basics first.
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### Author:  [@Tacoboy](https://forums.speedlife.net/u/Tacoboy)
#### Post date: [April 25, 2009, 9:52am UTC](https://forums.speedlife.net/t/whats-the-problem/123879/6 "2009-04-25T09:52:20Z")
Coolant bubble.
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### Author:  [@schwiin\_27](https://forums.speedlife.net/u/schwiin_27)
#### Post date: [April 25, 2009, 10:19am UTC](https://forums.speedlife.net/t/whats-the-problem/123879/7 "2009-04-25T10:19:47Z")
- 1 for the coolant , take the cap off , let it run, bleed it and make sure its full.
still rec tune up, fresh gas
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### Author:  [@91S131](https://forums.speedlife.net/u/91S131)
#### Post date: [April 25, 2009, 9:17pm UTC](https://forums.speedlife.net/t/whats-the-problem/123879/8 "2009-04-25T21:17:43Z")
search other recent threads for tune-ups and how to solve the idle issue.
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### Author:  [@89\_coupe](https://forums.speedlife.net/u/89_coupe)
#### Post date: [April 27, 2009, 12:24pm UTC](https://forums.speedlife.net/t/whats-the-problem/123879/9 "2009-04-27T12:24:48Z")
ok so i pulled off the iacv and cleaned it with air intake cleaner and put it back on. replaced a couple of the bad vacuum lines and my idle is still fluctuating.
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### Author:  [@89\_coupe](https://forums.speedlife.net/u/89_coupe)
#### Post date: [April 27, 2009, 12:32pm UTC](https://forums.speedlife.net/t/whats-the-problem/123879/10 "2009-04-27T12:32:41Z")
im thinking it is a bad iacv since my mechanic said that the tune up only makes it run better and doesnt do anything with the idle
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### Author:  [@87s15lt1](https://forums.speedlife.net/u/87s15lt1)
#### Post date: [April 27, 2009, 12:49pm UTC](https://forums.speedlife.net/t/whats-the-problem/123879/11 "2009-04-27T12:49:29Z")
a tune up has a lot to do with your idle. it just won’t seem like it if you have an over riding condition.
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### Author:  [@87s15lt1](https://forums.speedlife.net/u/87s15lt1)
#### Post date: [April 27, 2009, 12:49pm UTC](https://forums.speedlife.net/t/whats-the-problem/123879/12 "2009-04-27T12:49:59Z")
is she hunting or just idling high?
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### Author:  [@89\_coupe](https://forums.speedlife.net/u/89_coupe)
#### Post date: [April 27, 2009, 1:58pm UTC](https://forums.speedlife.net/t/whats-the-problem/123879/13 "2009-04-27T13:58:15Z")
when i start her up its sittin at about 1500rpm creeps up to close to 2000rpm then cuts off and drops to 1500 again. and it keeps repeating that. so i think i need a new iacv. all the vacuum lines are good. i replaced a couple that were staring to get bad.