95 gsx rough idol, some hesitation

[pimpin81]

Okay so i just put a low milage jdm 7bolt into my 95 gsx. the timing belt alignment marks were dead on i triple checked it before putting the cover on. I put all new gaskets on swaped everything over from the old motor that was different wich was practley everything, such as water pipe, coolant neck,intake manifold, turbo "t-25" ect ect. it was an automatic even swaped over the cas knock sensor ect ect.. only thing i kept was a jdm transferr case from a differnent 5speed awd jdm tranny that looked to be in better condition then my old one came



PROLBEM:: 1

Rough idol. The idol is prety normal as far as the base rmps but i have more vibration like the steering wheel shakes and what not. Just doesnt seem right to me. Also notice vibration in the higher rpms manily above 4k rpm but its not too terrible. and engine changes sound above 4k not a great sound eathier

2: feals like there is some kind of lagg on the drive train, bad gass milage and too keep a steady speed on a flat road looking at stock boost gage with pettle pressure right at steady speed sits 1/4 inch below ambiont or 0 psi.. Seems like i sould be useing less pressure to mantain a steady speed in 5th gear at 55-60

3: slight hesitation while boosting like a sudden slight jerk or nuge only once during 4gear pulls mostly

4: low oil pressure at idol like sitting at a stop light for example except for warm up then sits slightly above 1/2 way and also shows good pressure while cruzing..




Plugs,wires?oil pump balance shaft out of phase? base timing out of wack ?
im prety sure theres no boost leaks becasue it pulls hard just doesnt seem like the timing is right on the money. And the bad gass milage is killing me.


Im new to 2gs and this is my first one so i could really use some expert advice as funds are on the low end right now and cant afford shop rates.

 

[Jeff99GS]

Did you do a tune up on the engine before starting it? New Plugs, Wires, Oil ect.

Also I would still do a boost leak test just to be safe.

Triple check the timing...make sure all four TIMING marks are level with the surface of the head at TDC.

In the first picture I posted the timing is INCORRECT

The second picture I posted the timing is CORRECT

Hold a straight edge across all four timing marks.

 

[Colt4G63 also]

Plugs,wires?oil pump balance shaft out of phase? base timing out of wack ? CAS 180 off?

You have to check these things, I can't do it from here.

 

[joro702]

my car changed sound to when i got over 4 grand in any gear but now that i have an exhaust idk if it went away or i just cant hear it

 

[dsm03]

BLT, Check Compression, Spark plugs and Wires. and Check for oil leaks around the oil pump.

 

[Wicked95AWD]

My car had similar symptoms when the timing belt slipped a tooth.

 

[pimpin81]

I took the oil pan off cleaned it with a soft grinder wheel, then cleaned the pick up tube and oil pan on a solvent table. also put fresh oil in it and new oil filter all new timing components reused oil pump housing from old motor because had a tap for oil feed for my turbo."instead of getting it from the head" new thermostat ect. basically every gasket or filter was changed along with the pcv valve .before i started it.


I didn't put new plug's or wires on it. i used the plugs that were in the motor because they looked to be in great shape, i also reused the wires.

i guess i will take the top cover off bring it up to tdc and take a straight edge to the cams and see whats what.


The car drives pretty good , it doesn't seem like its gonna blow up or anything. just doesn't feel 100% with the vibration at idol the very slight hesitation on full throttle in 4th gear the drag on the drive-train and the low oil pressure at idol. and the weird vibration/noise around 4.5k which doesn't get worse after that ethier.


the car is stock , running stock boost 10-11lbs, have after market boost gauge, and a cone intake filter.

 

[Jeff99GS]

Does it have the balance shafts removed?

 

[pimpin81]

UPDATE

No still has balance shafts.


A friend who owned a dsm for a few years come over look at the car and take it for a test drive..


His diagnosis for 2 of my problems have probably been discovered..


PROLBEM
1: very slight hesitation

Possible Answer:

leaking from driver side exhaust manifold.

Gonna retorque the manifold.. its only been 850 miles since the swap so i suppose i should check everything anyway.


PROLBEM 2 :
Low oil pressure at idol..

Friend thinks it could be do to my sourcing oil from the oil pump housing for the turbo, and its robbing oil from the sending unit at idol and the turbo is getting more oil then the sending unit.


Problem 3:

Vibration at idol and at 42-4500 rpm only doesn't seem to be timing or balance shafts

Unknown, but gonna replace the plugs and wires see if that smooths out the idol vibrations.