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Surges when warm !!NEW CODES!!

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Old Jul 24, 2008 | 04:52 PM
  #1  
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Default Surges when warm !!NEW CODES!!

This is sort of a repost but here's what's going on.

Ive always had a surging idle when the car gets warm. It always happens all the sudden as if its something to do with the thermostat.
It will jump up to roughly 1600 rpms real quick then back down to 1100 rpms or so and stay there without going back down to the idle it was at when it was cold (750)
I've replaced the TPS, and MAP sensor as well as cleaned out my EGR and IAC.
After this, my cold idle seemed to be doing beautifully but i still have that horrble surging warm idle.
Ive also inspected some of the hoses coming out of the throttle body and only found one corroded one that goes down to the smog box on the passenger side.
I replaced that hose as well.

It surges in all gears, and throws the check engine light on. Mostly surging in neutral and park.
When put into reverse after its warm the rpms violently drop and the car either dies or has a hard time staying on.
It also says my oil pressure drops to 0 at certain points but i've blamed this on a faulty guage (which I could be wrong on)

Sorry for the huge wall of text, im just sick of it not being in tip top shape.

Thanks in advance!
Old Jul 24, 2008 | 07:32 PM
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Default RE: Surges only when warm

anyone?[&:]
Old Jul 24, 2008 | 09:15 PM
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Default RE: Surges only when warm

I had a similar problem with mine and I never did get to the bottom of it. So you mentioned MAP sensor so I am assuming you have either an 87 or 88 Stang so no Mass Air problems which would have been on my list of things to check. You've already checked all the other obvious culprits, how about one more thing, the VSS sensor on the tranny, this sensor is used by the computer to see if the engine is under load or not and adjust the idle appropriately, if its bad then it could be the cause of your problems.
Old Jul 24, 2008 | 09:17 PM
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Default RE: Surges only when warm

stop guessing what it is and run a koer test and pull the freakin code!!![&:]
Old Jul 25, 2008 | 08:29 AM
  #5  
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Default RE: Surges only when warm

ORIGINAL: SteveSkal

I had a similar problem with mine and I never did get to the bottom of it. So you mentioned MAP sensor so I am assuming you have either an 87 or 88 Stang so no Mass Air problems which would have been on my list of things to check. You've already checked all the other obvious culprits, how about one more thing, the VSS sensor on the tranny, this sensor is used by the computer to see if the engine is under load or not and adjust the idle appropriately, if its bad then it could be the cause of your problems.
I'll check that out, thanks!

ORIGINAL: mjr46

stop guessing what it is and run a koer test and pull the freakin code!!!
kk. I'll post a reply with my numbers
Old Jul 25, 2008 | 08:36 AM
  #6  
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Default RE: Surges only when warm

EGR delete solved my warm surging issues
my cold surging issues have gotten better but have not diapeared
Old Jul 25, 2008 | 10:20 AM
  #7  
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Default RE: Surges only when warm

EGR possibly stuck open causing a lean condition.
Old Jul 25, 2008 | 04:56 PM
  #8  
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Default RE: Surges only when warm

I'll get the codes pulled and if indeed its the egr, where can I get a delete kit?
I heard you can run into problems when deleting it.
Old Jul 25, 2008 | 05:16 PM
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Default RE: Surges only when warm

I just installed this one yesterday....http://rjminjectiontech.com/?p=9

You might want to replace every hose connected to intake. I recently did and found about every hose was cracked, detiorated and probably leaking a little. There 2 hoses on intake for pvc valve, 1 to the charcoal canister and the one to the MAP sensor(that one was nearly collapsed.
Old Jul 25, 2008 | 05:20 PM
  #10  
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Default RE: Surges only when warm

I talked to the guy at advance auto parts store he said he'd rent me out the code puller for cheap but he said he's not allowed to help me do it.

durrrr

So is there any tutorial on how to use it once I get it, and where does it show what codes mean? I would buy that eliminator but it's saying that there's no guarantee.
I guess i'll just wait till I get the codes.



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