Help trouble shooting.

[pingi3]

I have a couple of questions to ask and see if anybody has experienced the same issues. First is that when I am driving on the hwy, i will accelerate REAL slow up towards 4000 rpm in 3rd or 4th gear and it will start to sputter like it is starving for fuel. But if I get on the throttle no hint of it. revs right up through the rpm range. Oh by the way i have the 5lb roe system on my GTS. The car is tuned and is between 11 and 13.5 a/f. Any suggestions i can play off of instead of taking it to a shop blinded.

And the second question is my clutch would be mushy sometimes in the morning but after a couple pumps would stiffen up. But the other day I pushed it to the floor and it stayed there. The petal came up but no pressure at all and could not get it to engage 1st gear. After a few pumps it did engage but still half way. I came back later in the evening and it was fine. It was cold in the morning.

Thanks in advance.

 

[dave6666]

No comments on the Roe but your clutch I been there done that. Any visible fluid leakage under car? Not much in the system so not much to leak, but under the flywheel inspection plate area would be where slave leakage would be.

What's the level in the reservoir up top? If it is low probably the slave. If it is OK probably the master cylinder.

You can also just do a fluid change if yours is dark or old but usually that doesn't fix worn parts.

 

[bluesrt]

clutch sounds like a possible slave or master cylinder for clutch hydrolics, other fault u have is a tough one without feeling it in the car itself,but a guess would be some sort of ignition fault? but just a crazy guess.

 

[mike & juli]

Maybe a call in to Chuck Tator would be warranted? 1-914-763-3136 ~juli

 

[BOTTLEFED]

No check engine light?

could be ignition breakup - check your plugs and wires
also check you o2 sensors since they are only accounted for during closed-loop operation

 

[eucharistos]

Help trouble shooting.

remember to squeeze instead of pulling the trigger










sorry, just jealous of your Roe

 

[EllowViper]

The mild accelleration stumbling is tricky. Lots of intertwined issues that I've pondered/addressed over the years as well. Closed-loop vs. open loop transition during other than WOT accelleration, individual injector trim, base fuel % offset, 02 sensor location (with headers), heat range of plugs/gap, potential vacuum leaks, bypass valve, TPS signal, VEC ground, short runner manifold design...you get the idea. Since this appears to be a closed-loop tuning issue, I'd focus on your base injector % and make sure your LTFT are within +/- 3% of zero on banks 1 and 2. Need an ODB-II data logger to check that. It would be good to pull a few ODB data logs too to see what the closed loop timing and fuel trims are doing IRT RPM and load as well. Since the VEC really doesn't address closed-loop tuning other than base injector % and injector trim, a SCT flash might be in order to bring your PCM into sync with what your engine is telling you. This is where I see the future of having a SCT flash capability married to a VEC. Checking into that myself right now....