Loss Of Power Above 5000 Rpm Help!!!!!!

[svtff2003]

when the rpms get to about 5200 rpm there is a loss of power it sort of sputters and pops i have no idea what the problem is, i put in brand new factory spark plug wires and brand new factory plugs. BTW its a 98 GST

 

[ryno]

How much psi are you running and do you have any fuel mods?

 

[TooFastTooG]

This really wont help with the poping or sputtering noises, but just to let you know your stock t-25 (if your still running that) drops off at about 5000 rpms.

 

[svtff2003]

I still have the stock turbo and there are no fuel mods. Could it be a boost leak or a sensor? I am running stock boost too

 

[DSM_TSI_95]

You should check your intercooler. I had this same problem on my 95 gsx and it turned out that my inercooler was bad.

 

[eclgst95]

You should check your intercooler. I had this same problem on my 95 gsx and it turned out that my inercooler was bad.

How can the intercooler go bad?
I use to think I had the same problem. loss of power after 5500rpm.
But after alot of work ive just come to the conclusion as someone else just said that after 5500rpm the turbo stops pushing the power anyway

The sputtering could be fouled plugs and possibly wires or the coil pack.
Maybe even bad gas?

 

[DSM_TSI_95]

All good theorys on that. Im just saying that i had the same problem with the same turbo. I changed plugs, wires, gas, coil, just about everything. Then i had my intercooler checked and it checked bad. I replaced the intercooler and my problem was fixed. This is for the sputtering side of the problem. The turbo does seem to stop pushing at around those rpms i aggree with you there. I would check my intercooler before i started throwing parts at it though and if it checks good then proceed from there to bad gas, plugs or wires.

 

[svtff2003]

Thanks for the advice i'll definately check the intercooler cause i replaced just about everything else

 

[eclgst95]

All good theorys on that. Im just saying that i had the same problem with the same turbo. I changed plugs, wires, gas, coil, just about everything. Then i had my intercooler checked and it checked bad. I replaced the intercooler and my problem was fixed. This is for the sputtering side of the problem. The turbo does seem to stop pushing at around those rpms i aggree with you there. I would check my intercooler before i started throwing parts at it though and if it checks good then proceed from there to bad gas, plugs or wires.

I still dont understand how a intercooler goes "bad" WTF
Im sorry but can you please explain this? When i go to look at my intercooler I want to know what to look for.

 

[oldman]

Boost leak test.

I still dont understand how a intercooler goes "bad" WTF

A leaky IC = a bad IC.

 

[DSM_TSI_95]

As old man has said.An intercooler that leaks will give you some problems as svtff2003 is describing.

 

[TalonESIT]

i had a similar problem... could you describe more about what happens? does it just stop accelerating and the exhausts just starts popping? because i just finished finding out why my car was doing that too. because of my wideband reading so lean i realized i needed to turn up my static fuel psi to compensate for the air, i originally lowered it because i figured the mixture was too rich before i installed my wideband. one time when i was boosting too my cold pipe disconnected from my intercooler! Huge loss in power but it was a much different feeling and there wasn't nearly as much popping coming from the exhaust... hope this helps somewhat.



i'm sorry i didn't realize you were still running on stock boost, i may be totally wrong then; my apologies.

 

[Sweetridez]

My friend had the same problem with his car and he has the same setup as yours.After 5000K his car would start sputter and make differnt noice . He found out his timing was a little off thats why he was loosing all that power and making wierd nice.

 

[amaank]

Octane value? if 2gs have that...

Perhaps try resetting your ecu. My car had huge power losses at 4ish-5kish until i reset it.

 

[svtff2003]

How Do You Reset Your Ecu?

 

[eclgst95]

Yes how do you reset ecu? Disconnect the battery for 10min?

 

[titogs95]

Yes how do you reset ecu? Disconnect the battery for 10min?

Yes, disconect the negative. but, not for that long 1 min or so should be enough.

Also if you have any datalogger or Obd-2 reader you can manually delete it.

 

[talontsi9095]

It may be your intake manifold gasket.