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new to this forum due to issues im having with my car. hoping someone can shed some light and direct me in the correct way to resolving this issue.

 

my car is a 2008 LGT limited the car is automatic

 

problem i am having is a pulsation in power that happens during light and heavy acceleration.

 

idles perfectly fine has no engine light no codes pending current or in the history and from everything ive looked at with my solus everything seems to check out.

 

during light or heavy acceleration it seems to be pulsing or randomly cutting the power down. instead of just a smooth accell it keeps dropping down a few hundred RPMs then back up then cut then back up ect.

 

car only has 48k miles and doesnt have any performance upgrades.

 

only other thing i had noticed in my adventures of trying to pinpoint the problem is if i am driving along in inteligent mode and it starts to pulse if i switch it to sport the pulse gets worse or sport sharp pulse gets even worse.

 

im hoping someone can point me in the right direction of where to go with this problem.

 

and in case this information helps it seems to have starting doing this more recently as the weather has gotten colder i live in upstate ny. any advice would be greatly apreciate.

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during light or heavy acceleration it seems to be pulsing or randomly cutting the power down. instead of just a smooth accell it keeps dropping down a few hundred RPMs then back up then cut then back up ect.

 

A very similar thing was happening to me. The RPMs never actually dropped, but you felt the power drop then rise again. Turned out the PO had NA plugs with a .45 gap. Put the correct plugs with .30 and it runs great now.

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I did check for vacuum leaks with a smoke machine and good ol carb clean didn't find anything. I will check my plugs tomorrow and go from there. I've read some things about ecu programming? Other saying similar issues have been corrected with an access port tuner. It's pulses most between 2200-2600 but even under heavy acceleration it will randomly cut power and sometimes it even seems to lack in power compared to other times. Frustrating just bought the car 3 months ago
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dropping down a few hundred rpm? leads me to suspect the issue has something to do with the trans. i would think bad plugs would cause more of a stutter than a pulse. the AP would let you monitor what the ecu is seeing and doing... but i doubt you need it to solve this issue.

 

intelligent, sport, and sport sharp are used to change the throttle curve, right? So maybe clean your throttle body? clean your maf and air filter while you're at it. you could try applying a small amount of dielectric grease to some of the harness connections, but do your research on that one.

 

good luck m8

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Yeah plugs were perfect didn't suspect they would make a difference trying anything at this point. It doesn't seem like a transmission issue it shifts great and smooth I guess it's a possibility always but with no codes or anything it aucks to track down. I'm going to clean my throttle body maf and all that tonight and see if that makes any difference thanks for the input.
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Yeah plugs were perfect didn't suspect they would make a difference trying anything at this point. It doesn't seem like a transmission issue it shifts great and smooth I guess it's a possibility always but with no codes or anything it aucks to track down. I'm going to clean my throttle body maf and all that tonight and see if that makes any difference thanks for the input.

 

A note about cleaning the MAF. I had a problem with the MAF on my X5 and cleaning it did nothing to solve the problem. Replacing it did. While it doesn't hurt to clean it keep in mind, if the problem persists afterwards, the MAF could still be a problem (though, in my limited experience, problems with the MAF throws a code).

 

Good luck. I know it's frustrating buying a new vehicle and immediately having problems with it. But once you get it running right you'll forget all about it and enjoy your car.

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The the problem happen mostly between 2,000 - 3,000 RPMs? If so, then you have the famous stumble that most of have. In most causes it's an easy fix by moving a few vacuum hoses around by the fuel pressure regulator.

 

When this happens, sometimes the car will go into "limp" mode as a safety measure. Then after a while it will return back to normal power.

My wife's balls are delicious.
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use your solus and check out the TCM. monitor your engine speed input and see if you have any issues there. it kinda sounds like a "spark" issue that's causing your transmission to stutter. if the ESI seems a bit off, you could always clean/replace your cam and crank position sensors. I thought my tranny was dead -- replaced the two cam position sensors; tranny was flawless again. it's worth a shot
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The the problem happen mostly between 2,000 - 3,000 RPMs? If so, then you have the famous stumble that most of have. In most causes it's an easy fix by moving a few vacuum hoses around by the fuel pressure regulator.

 

When this happens, sometimes the car will go into "limp" mode as a safety measure. Then after a while it will return back to normal power.

 

It's definitely between 2-3,000rpm where the main problem is just cruising along with my foot on the gas it will bounce between 2,200-2600 what hoses do I switch where ? Will to try anything at this point

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