Pulled onto highway 1st- 7K rpm, 2nd - 7K rpm, 3rd - stutter lunge lunge, let off , and throttle again, now smooth acceleration.

Same feeling as when learning to drive MT in 1st and not giving enough gas or letting clutch off too soon. Feels like the car is skipping instead of running.

(Have a single plate Helix clutch, light tune - ecu cams F.pump exhaust.)

I know that the gearing is high so letting off the gas has a similar effect of lunging. But wouldn't see why this would happen accelerating.

Has anyone else experienced this? Normal or problem?

 

My car has done this exact thing to me as well. Once a long time ago, but a couple times in the last week. Only in third gear as well. I checked my intercooler hoes thinking I might have blown one off, but it wasn’t that. Hopefully someone who knows what it is will chime in.

Nick

 

Mine did that a few times in the last couple of weeks. It does it in third gear too. Strange.

 

Mine has done something similar to that, but it was in 2nd gear. Normally high in the RPM's without pressing the petal to the floor. I just assumed that I was going to easy on the gas.

Same thing?

 

My 96 GTI VR6 did the same thing in 3rd gear and so did my 01 GTI 1.8T. I don't think it's manufacturer specific. Thought it was either a scavenging problem with the fuel pump or a dirty fuel filter but never nailed anything down. My EVO hasn't done this yet but I do expect it will happen eventually.

 

What your describing sounds like fuel cut.. it happens more frequently when the air gets cooler and more dense..

But it doesnt happen all the time, and doesnt always happen and sometimes its different for different people, but happens consistently for the individual..

Sometimes it could be misfire, but what your describing sounds like fuel cut (Bucking and whatnot)

There's things you can do to reduce it or eliminate it, but it depends on your level of modification (if any)

 

You may be misfiring. I suggest first changing you plugs to NGKBPR9ES. They work very well for a bunch of us at the shop. It may be running too rich, but I don't think that is your problem considering it only does it in third. It also may be detonating. I once had this problem from a poor tuner and eventually boom there went my engine. I didn't no jack when I was getting started so I thought it was only bad gas. Check your tuning. Every car is different so if you just plugged in some numbers you got from somewhere then they might not work for you. Good luck and be careful.

Matt

 

If it is fuelcut then it would probably back fire when letting of the throttle, I think??? I use AEM EMS and if I hit the rev limiter it backfires.

 

If you blow off an intercooler hose, you'll know it. The car won't climb even a slight grade and misses if there is ANY boost.

Don't ask me how I know.


(Old guy who lives in mountains)

 

Change your plugs, I was experiencing something like this, put new plugs in and bam problem solved. I noticed the problem in higher gears when the engine was under a bigger load.

Shane

 

Fuel cut doesn't cause a backfire, ignition cut however would..

 

Yep thats another good point.. but misfire is more subtle than bucking like that.. its a good idea to change your plugs anyway..

 

(modifications: tomei ECU + poncams/ 255L pump/ FPR/ decat downpipe cat back)

Plugs:
Just had plugs changed last month. NGK

Weather:
The weather has gotten cooler here.

Fuel cut:
Don't think it is fuel cut. Had that on skyline and that feels relative to how I describe the lunging to being more severe, acceleration spikes are more violent where your body would leave the seat. This was more like a FWD jerking where cut or decrease in acceleration band was not enough to jerk my out of my seat. But different car so possible... Inputs on what confirmed fuel cut feels like on EVO?

IC pipes are fine no leaks

I had it in full throttle when it happened, backed off on it and full throttle again, it was normal.

 

Well what happened with me was car was jerking when engine was under load in high gears. turned boost down a bit and it seemed to help a little bit, not really. Changed plugs and it solved the whole problem, was able to turn boost back up with no problems. When this was happening it wasn'tviolent at all kinda felt like good power then lost power, good power then lost power when boost was applied. Make sure your plugs are gapped correctlly. Also even though they are notthat old make sure they are not fouled.

Shane

 

i have the greddy ti, helix dp and cat delete, turbo xs bov, helix ic piping, arc intake, and after I put the 255 fuel pump in an hour later my car stutters when boost kicks in at every gear! Can anybody help me, the pipes are on perfect, the fuel pump is on perfect, so im thinkin dyno flash because I am runnin way to rich ? I might get a dynoflash monday, can somebody confirm this and let me know if this will fix the problem thansk