96 gts running rough under load

[chris gts]

Car starts and idels fine. But as soon as you set it out and start to drive it around 3 thousand rpm the motor starts cutting out. You can through it on the floor and the rpm gauge wont move but after a few seconds or so it will take off like a jet. I have replaced plugs and its still doing it. I need to get car running in tip top shape got a buddy with a rousch 427r mustang just waiting to clean my clock. I dont really no how bad it is any help would be aprecative on both problems.

 

[dave6666]

There's almost a bottomless plate of things it could be, within reason. How about a more detailed list of any mods that have been done, and more importantly is periodic maintenance up to date? BTW, that list of PM stuff if done thoroughly, may be longer than you realize. Another pertinent item might be how many miles on the car.

 

[chris gts]

The car has 46000 miles on it edelbrock headers gtsr exhaust just put a new water pump and power stering pump on it wit roe racing pully and billet bracket,smooth tubes and green air filters. I have also put a new fluydiane radiator 170 thermostat and silcone hoses. Took it to a viper tech in lexington ky last month for a check up and every thing was fine and now just last week this has all started so i put new plugs in it and still the same problem going to go with wires a coils next.

 

[dave6666]

When was the last time plug wires were changed? Battery was replaced? Can we assume no CEL's? Did the problem all of a sudden show up? Or show up after a mod or...?

 

[chris gts]

I have just owned the car about 3 months. The problem started after my power steering pump went out. But I know the spark plug wires arent stock they are ac delco performance 8MM wires and im sure the coils are stock. When it starts doing this you can push in the clutch and it clears up but just as the car comes back under load it happens again.

 

[99 R/T 10]

I would say go with a plug wire change out, just to be sure. It could also be a cam or crank sensor going bad. I would replace them both, cheap insurance. Check your *** Chris.

 

[dave6666]

I know the cam sensor is in the general location of the power steering pump, not that it could be related to a pump failure. Unless a wrench slipped and knocked it or the connector during the pump replacement.

When you do the plug wires pay careful attention to routing - try not to cross or weave the wires - and appropriate heat shielding of the wire at the plugs and along the headers. Make sure at the coils every thing snaps in tight, and be sure to use the dielectric grease on all of the boots.

 

[Leslie]

Car starts and idels fine. But as soon as you set it out and start to drive it around 3 thousand rpm the motor starts cutting out. You can through it on the floor and the rpm gauge wont move but after a few seconds or so it will take off like a jet. I have replaced plugs and its still doing it. I need to get car running in tip top shape got a buddy with a rousch 427r mustang just waiting to clean my clock. I dont really no how bad it is any help would be aprecative on both problems.

I had a VERY similar problem this past Sun. at the track. Car was overheating (running 70-100+mph in 3rd gear most of the course), so I started trying to run in 4th and 5th gears. Put my heater on blast (yeh it was 85 degrees outside) and that brought my temps down but kept dying under load, same corner.

Came out of a turn and it's like the car died, no pwr, then it came back.

Found this thread when I was doing a search for heating issues, good suggestions, thx.

 

[Madduc]

Also if you are going to replace plug wires, search here for AB Qualitywires...best there is. Also call Chuck Tator(viperwizard) and inquire about "Field dump" clearing the computer.

 

[Janni]

We had a similar goofy issue with our 1996 GTS. It would be ok when it was in "openloop" - i.e. WOT or when it was warming up - then would stall at lower RPMs.

It was a faulty ground on the Idle something or other, IAC (?) or intake air thingie (I'll call Tom Sessions and update this post with the proper part.

UPDATE - we regrounded the TPS (Throttle Position Sensor). It's actually BETTER to reground the sensor ground into the PCM and run it to the stud on the drivers side. NOTE - DO NOT do this if you have an AEM. It will make it MOST unhappy.

We swapped out the parts thinking they were bad and it was a bad ground. Ran another ground wire and it was a happy camper. Apparently this is a common issue on older vettes and other cars that are not metal bodied as there are few ground points and sometimes as things age, the ground gets lost.

The fix was cheap and instantaneous. (After we swapped 47 parts off of the 1998 race car motor...)