2g Stuttering at 4300 rpm in first gear only

[97FairGame4g63]

Hey I bought my car used in June. It's a 1997 GST with a built bottom end stock head 4g63. The car has 95 eprom ECU, FMIC, Evo 3 turbo and manifold.

The car also has a 2 step but I'm not sure how it's set up and I don't know where to start looking. In first gear if you pull away like normal it's like he car is trying to do a 2 step at just over 4000 rpm while it's moving. The clutch switch isn't hooked up and I see a couple wires spliced in. When I connected it the car wouldn't crank over at all so I left it. I'm just not sure if someone installed a WOT box wrong?

 

[cmehlxl]

i had a problem with a bad spark plug/boot/coil that would produce similar results around 5k, voltage would drop and battery light would flicker and car would stutter/jerk. changed plugs/boots/coil and issue was resolved.

however, since you're unsure about the ecu/ 2step install it makes it trickier to diagnose without throwing a stock ecu to ensure it's not your ecu or deleting 2step control to see if that has an effect..

 

[TehRiceBandit]

Look up a video of a slipping clutch on YouTube and see if that's what you're talking about. I'm not entirely sure of what you're describing.

 

[Chumpaumpalumpa]

You have link, correct? It's very simple to use. Go to the RPM tab and set the enable launch limit speed to 5mph. Also post a log or a screenshot of the tab.

If you don't have it on your laptop then PM me and I will help you get it set up .

 

[2gmitsueclipse]

OP; If you are not sure about what method of tuning was done to the car, you may want to pull the ECU out and open the case.

A log would be nice. Do you have a wideband?

Other then that, I would complete some standard procedure troubleshooting such as boost leak test and checking condition/gap of spark plugs.