Slight lurching feeling in 3rd and 4th gear

[Darizey]

Greetings everybody, thanks in advance for reading and possibly helping out with this issue.

I have a 98 Eclipse RS, stock, just purchased not too long ago and having an annoying issue. The vehicle accelerates fine, and at WOT its fine, hell even cruising in 5th its great, but when I am in 3rd and 4th gear, cruising around 2700 rpms or so, the car feels like its lurching ever so slightly. It still has great throttle response, no lose of power, RPMs arent bouncing around, but it feels like you're just tapping the gas lightly then letting off.

There's no CEL, changed plugs, oil, and ran seafoam when I first got the vehicle. Checked hoses and vac lines and nothing stood out as damaged or missing.

Any ideas or suggestions would be greatly appreciated. Thanks

(I tried searching and found plenty about lurching when you get on the throttle, but nothing like this)

 

[Darizey]

I just replaced the plugs when I bought the vehicle with NGK plugs. I guess I'll pull em and double check the gaps. Thanks.

 

[Darizey]

Alright, so I finally got around to checking the spark plug gaps and they were gapped incorrectly. Increased the gaps to .045 and ran it for a while. Unfortunately I am still having the same issue.

I am also trying out running midgrade fuel to see if it runs any better.

I guess the next step is to r&r the tps, but thats gonna be a huge pain because the bolts are stripped so I have to remove the whole throttle body first.

Anyone have any ideas what else it could be?

 

[Darizey]

Alright, replaced the TPS, cleaned the throttle body, cleaned the IAC, put everything back together and it seemed to have improved a little bit but I'm still getting a bit of bucking at the low to mid range of rpms. Not sure where to go next, so any help would be greatly appreciated.

 

[Darizey]

(Starting to feel like I'm talking to myself here)

Searched for a vac leak and wasnt able to pinpoint one. Currently working on getting the funds together to replace my cracked exhaust manifold and leaky exhaust pipe, and will delete the cat in the process. Still have no idea what to look at next to try and figure this out.

 

[952g63t]

Have you checked your fuel system? You would be amazed at how well a car responds to fresh injectors and filters.

 

[jakk220]

Are you sure that it's not drivetrain related?

 

[Darizey]

I was just thinking about it today and figured fuel system would be my next step since I dont know when it was serviced. I'm gonna pick up a new fuel filter today and see if that helps out at all. I've run Lucas thru the system a few times and seafoamed it after I bought it.

I was also thinking it may be drivetrain related but I'm clueless as to where to begin with it.

I am also going to look into issues possibly with the EGR system, and may just delete it.

Thanks for the responses, I'll let ya know what I come up with.

 

[BoostforBreakfast]

gap them to .030

 

[Darizey]

Why .030? Every thing I have found on here says .045. I cant really tell if there was a difference, if there was it wasnt very significant. Mileage and power seems to be the same.

 

[Darizey]

New test pipe and cat back on its way, already have the header and downpipe, so hopefully Monday I'll be able to get that all installed and who knows, maybe that will fix my problem (yeah right).

 

[Darizey]

Does anyone think this could be a fuel issue? Maybe injectors or fuel pump? Is there any way to test the injectors still in the vehicle?