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problem and i'm not sure...

hyped

hyped

New member
Hi everybody,
I should start by saying that I'm not the most mechanically inclined person, so bear with me (as this might be a dumb question or have an obvious answer)

I picked up a 97 gtp with 220k kms on it for around 3 grand in November. It needed its share of maintenance (filters, fluids, headlights, tires, etc) but nothing too big. Up until yesterday it's been great and a blast to drive, but when I was coming home from school on the back roads and I put my foot into it, it flew up to 80-85 km/h and wouldn't go any higher under heavy rpm and full boost (which I quickly let off).

I took it around the block again and gave it another go, and it didn't happen again–it was totally smooth. My guess is it's to do with the transmission, but I honestly have no idea :th_nervous: anybody have any input? it would be greatly appreciated.
 


Most likely KR of some sort.

Have you already done the plugs, wires and basic tune up stuff?
Was the check engine light flashing while it wasn't accelerating further?
 
So, for us americans that's between the 45-50 MPH area, if I'm not mistaken. That is around where you should be shifting from second to third gear on a factory tune.
 
it's got new spark plugs, oil, blarby-bla bla. most of the things covered in the "safely modding your 3800" thread's maintenance section.


no lights were on.
 
sorry to necro this thread, but it's still doing it, and it's every time now. i've had some suggestions from neighbors who think it might be to do with the gas circulation (??) but I don't think that's the problem. The only way I can really describe what's going on it once it gets to around 90 km/h under heavy (not even full now) acceleration it just kind of chugs around...the engine goes and stops and goes and stops and goes and stops. I'm still pretty sure this is a tranny problem, can anyone shed some more light on this? I'm trying to be patient but I'm getting sick of this :(
 
So the check engine light wasn't on steady, how about flashing? It's tough to fix a problem over the internet when the guy who needs to provide details saying that he changed blah blah deblahey.. :th_laugh-lol3:

Many of us would like to help you for free, but it you don't provide clear detailed answers... see the point I'm making? :th_thumbsup-wink:

Let's take a couple steps back.
Check engine light flashing when it's doing the issue?
What octane of fuel are you using?
What spark plugs did you put in and how long back?
Did you change the plug wires?
Are the #4 or #6 plug wires touching the O2 wiring?
Have you checked for vacuum leaks?
 


:th_laugh-lol2: Sorry. I appreciate any and all help I can get. The deblabla bit was just that I've done most of the suggested things you do to a used GTP when you get it from the Safely Modding your 3800 Powered Car thread.

Check engine light flashing when it's doing the issue?
What octane of fuel are you using?
What spark plugs did you put in and how long back?
Did you change the plug wires?
Are the #4 or #6 plug wires touching the O2 wiring?
Have you checked for vacuum leaks?

No CEL flashing or solid.
I'm using 94 high octane.
I'm not sure what the plugs are but they are from last November (receipt from seller). I'll see if I can find out.
I think the wires are new as well. Again, I'll try to find out.
From memory, all the plugs are clear from touching anything. I will check!
I haven't checked for vacuum leaks yet but will do so when I get home. I think there might be a little one (just guessing), will let ya know.

Thanks. :D
 
Sorry for taking so long. Finals are keeping me busier than I want to be. :th_nervous:

Couldn't find the receipt for the plugs and I have no idea what they are, sorry.
The wires are indeed new from November, they're NGKs.
4+6 wires are not touching the o2 wiring.
Still haven't checked for vacuum leaks, going to try to either tomorrow or Saturday.

Thanks again :th_thumbsup-wink:
 
Remove your front o2 sensor and see if the problem persists. Its gonna be load just to warn you. Dont forget to put it back in when your done. My car did that when my cat was plugged would go fine till about 40-45mph then it would bog down, but my CEL flashed at me.
 
Correct me on this if I'm wrong but on the 97's there is a knock module that plugs into the pcm that is holds the crank learn. Maybe that module has gone bad. Seems strange though no codes so I might be wrong on this, but still something to check.

Some info on a typical GM knock module.

Knock Modules.

The Knock Module monitors the Knock Sensor's AC voltage signal
and supplies an 8-10 volt signal to the ICM if no knock is present.

If spark knock IS present then the Knock Control Module will remove the 8-10
volt signal going to the ICM.

A loss of this 8-10volt signal will cause the ICM to
deactivate the MBT (Best-Mean-Timing) feature which will
drop the timing to a safe level.

Always use the correct Knock Module WITH the correct
knock sensor or you will have problems.
 
Last edited:
The knock module isn't a typical culprit.. Let's aim for the easy things. Like unknown plugs and wires. :th_winking:
 


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