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Loss of power and rough idle.

1927 Views 13 Replies 7 Participants Last post by  eouellette18
I'm still experiencing a loss of power and a but if a rough idle. The rough idle happens mainly when I'm decelerating. It will boince around all the way between 500-1000 rpms. Once I'm at a full stop its not too bad. It may bounce between 700-800 rpm but that's about it. I replaced my air filter on my jlt cai, cleaned my MAF (maybe not enough? I only gave it about 5 sprays because the autozone dude said to use it sparingly) I even replaced the throttle body fully for a new oem one! My thought is my spark plugs need to be replaced. My car has 67000 on it. Still original plugs. I'm just at a loss right now. Please help!

---------- Post added at 10:09 AM ---------- Previous post was at 10:06 AM ----------

Please excuse all the misspelled words. I'm using my iPhone! Lol
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I am experiencing the same problem with my 04 GT at 67K miles. I replaced my spark plugs with NGK Indrium and I think those are giving me problems. I also am experiencing shaking at higher speeds (may be my tires though)
Did you clean your IAC? Also do you feel the power loss at any other time?
How do you clean the iac. And the car just doesnt feel as powerful as it did. I'll push on the accelerator and it feels sluggish. I used to run the 93 race tune from bama, but I switched it to stock settings after replacing my throttle body. Would a clogged fuel filter or fuel injectors cause this too?
Rough idle, power loss seems like a vacuum leak. Check you're hoses to make sure you're not leaking
How do I check for vacuum leaks? Like what hoses and where should I be looking for/at?
How do you clean the iac. And the car just doesnt feel as powerful as it did. I'll push on the accelerator and it feels sluggish. I used to run the 93 race tune from bama, but I switched it to stock settings after replacing my throttle body. Would a clogged fuel filter or fuel injectors cause this too?
eouellette18,

Yes, a clogged Fuel Filter or Injectors could potentially cause hesitation or sluggishness. At the minimum, I would replace the Fuel Filter, since they're relatively cheap and easy to install!

I see you mentioned after switching to the factory tune, you're are still having issues. Have you tried adjusting and tightening the CAI, as I mentioned in your previous thread? A very simple/small air leak will cause a lot of issues!

Shane
I haven't tried adjusting/ tightening it yet. I also replaced the cai filter with an autozone filter as it was cheap and quick replacement. Could that be not sealing right or something?
Will definitely try these sugg. Since I to am having same exact issues on idle
I haven't tried adjusting/ tightening it yet. I also replaced the cai filter with an autozone filter as it was cheap and quick replacement. Could that be not sealing right or something?
I doubt the filter is your problem, considering the issue accorded before and after the filter replacement. Make sure you check every coupler in the intake. Make sure the fitment is perfect and you tighten all the clamps. As I said before, this is an easy issue to have if there's an air leak in your CAI.

Shane
Ok. I'll check tomorrow. I also reinstalled the 93 race tune. Some times it pulled really hard like it should, and others not as much. Could this be from malfunctioning spark plugs? I'm also in need of tires. Could that be part of the feeling that its list some grunt just because its not hooking up as well as it should? I'm also thinking the issue is either spark or fuel related because the throttle response doesn't seem quite as quick as it once did.
You went back 2 tha stock tune its gonna feel slugish ..and ur gonna lose throttle responce..ur prolly putting regular gas in it 2.....its just gonna happen..
Yes, but even going back to the 93 octane tune it feels sluggish at times. There will be times that it pulls really hard, and other times it doesn't as much.
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