99 GSX.... lags/hesitates when you push the gas? fuel pump?

[MXRider04]

i have a 99 gsx. i been working on it for almost two years and its finally almost drive able. i having a problem with it and think it might be that i need a better fuel pump or fuel regulator? When you press the gas to move it hesitates and theres a delay when the cars about to move. Its a real pain... Sometimes i even stall out because the delay is long enough that the rpms go to far down before the car actually kicks in to move. any suggestions appreciated!
thanks alot!

 

[khawks]

MAF sensor? mine was broken and did the same thing

 

[talonguy85]

Is the car throwing a cel?

 

[MXRider04]

ill have to check the maf sensor... as far as CEL i have no idea!? i had to tear apart the whole dash to replace the heater core. While doing so i found that the bulbs for my tach are all burned out. So im going to have to replace the bulbs to see if the CEL comes on.

 

[immortalmcf]

hook up the scanner and see the code if u dont have a scanner go to autozone and keep us updated

 

[TopGun8818]

Sounds similiar to when I needed to replace my fuel filter on my old car. Have you changed the fuel filter in the time you've been working on the car?

 

[Outdorsman]

Heres the worst case scenario and I had the same exact symptoms as you. You may not like em but its what caused my issue and another members with the same symptoms:


Blown Headgasket between two cylinders or you jumped timing. Compression test and check your timing. Hopefully you're lucky.

 

[Timechg]

I wouldn't jump to blown head gasket or bad timing yet, but it could be a worse case scenario. Have you checked your throttle cable position as well as tps sensor adjustment? These can cause a lag between pushing pedal and going forward and could cause stalling problems.

 

[acorn3583]

Our Spyder always had problems like this. Make sure your throttle body isn't sticking and the throttle cable isn't loose or anything simple like that, but definitely take a look at the fuel filter and some of the other delivery components. Check the small stuff first Good luck, man!

 

[Outdorsman]

Run a compression test to check the health of your engine. And check timing like I said, it literally takes like 5 mins and could give you room to breath unlike me :/. Like he said, do easy stuff, can't get easier than turning the crank pulley til TDC or sticking the gauge into the spark plug holes haha.

 

[vr4joe]

Have you run an inter cooler piping test. Could have blown a coupler or small leak somewhere. Does to run idle rough? Do you have the stock by pass valve? I know the VR4's are known to leak when they get old. Wasn't sure if this was a common Mitsubishi issue.

 

[DEADKITTY]

I think it could be a throttle cable issue maybe it came lose some how. My friend had a similar problem and that's what it was. Its an easy fix.

 

[CleverDSMusername]

Sounds similiar to when I needed to replace my fuel filter on my old car. Have you changed the fuel filter in the time you've been working on the car?

+1 on the above, sounds like a fuel filter to me as well. i've seen hyundai's, kia's, ford's, old cadillac's, chevy's, & honda's do the exact same thing.