The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support Morrison Fabrications
Please Support STM Tuned

1G Evo 1 Hesitation / Jerking low or high rpm load.

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Wrathvr4

Proven Member
47
11
Sep 15, 2021
Brisbane, California
Hoping i can find some help here, as heading says, i'm experiencing hesitation / jerking under low and high rpm. i must admit i am a newbie when it comes to analysing Logs, so im hoping someone here will be able to point me in the right direction as i am all out of ideas.

so far i have done Boost leak test, re gapped plugs to 0.20, checked fuel system (pressure is good) and COP system seems good (no load)

evo 1 4G63T 2.2L Stroker

if anyone is able to shoot me any advice what i should be focusing on would be much appreciated.
 
Can you post a log? It will "say" a lot (if you are using DSMLink).
 
i should have mentioned, im using LINK G4X ecu please find attached a small clip of whats going on, if you need anything else let me know. thanks heaps
 

Attachments

  • Hesitation.zip
    1.1 MB · Views: 18
It’s actually a new tps unit however I will test that today 🙏

Could be the throttle position sensor throwing some bad readings
You must be logged in to view this image or video.

As you can see from that vid. The tps does seem to be jumping with throttle off. Will test now and see if I’m getting the same result with multimeter
 
That's pretty normal behavior for any sensor in my experience.
Yep and after just testing tps it looks to be functioning correctly. The one thing I haven’t done is pull the injectors. They are almost brand new ID1700 so I’m sceptical that those are the cause
 
Yep and after just testing tps it looks to be functioning correctly. The one thing I haven’t done is pull the injectors. They are almost brand new ID1700 so I’m sceptical that those are the cause
I cant look at the logs until tomorrow but G4X is much more complicated than ecmlink and it's very easy to get little nagging issues like this if you're not a great tuner.
 
I cant look at the logs until tomorrow but G4X is much more complicated than ecmlink and it's very easy to get little nagging issues like this if you're not a great tuner.
I hear ya, was running just fine a week ago on current tune. So the problem is within my system. I’m hoping the logs can tell a story
 
As you can see from that vid. The tps does seem to be jumping with throttle off. Will test now and see if I’m getting the same result with multimeter
my tps values stay constant at around .8 volts? I think at idle.

You will need a volt meter to properly adjust throttle closed voltage settings. They can be found in these forums
 
If the sensor doesn't react smooth on the meter (I'd use an analog one for this stuff), then it will give erroneous info to your ECU. It should transition smooth from nothing to full throttle no matter what kind of TB you have.
I wish @GST with PSI Brett was watching this thread LOL.
 
What TPS are you using ? I can't tell from your video.

In that log fragment was the throttle steady and that was all noise or were you playing with it? I assume you were trying to run it through it's range but lets be sure (pedal or by hand at the TB)

What does the LINK G4X ecu want to idle TPS voltage. What's normal for a DSM/EVO isn't necessarily the same with some other ECU.

A profile on this car would help along with some pictures.
 
I had a double-whammy on my S2000 once. The TPS wasn’t working properly, which caused hesitation and bucking, so I replaced it with an Omni TPS sensor. Didn’t fix it. When wiggling the wiring, it caused the TPS voltage to fluctuate, so I replaced the wiring pigtail. That fixed the floating voltage issue when the wiring was wiggled, but it continued to buck while driving and it had a dead spot on the pedal. I tried the stock TPS again and everything worked beautifully - the Omni TPS caused the hesitation. It’s possible for both the TPS and wiring to be bad.
 
swapped out the TPS and problem solved!! such a wank when the unit in it was also new. all good though, just happy to be boosting again. thanks for every ones help
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top