Sluggish acceleration

[jedi]

My 95 automatics acceleration has been getting a little sluggish lately. When I try to accelerate in 2nd or 3rd I have to get on the go peddle more than normal to get that corvette feeling. SO...I took it to a tranny place today and they could not find anything wrong. What else could cause this type of issue? It does not happen all the time. Just sometimes it does not accelerate as quick as I am used to. Could it be in my head? :crazy
Jedi

 

[Ken]

It might be in your head, I've been thinking the same thing lately about my truck; it seems like I gotta put more of my foot into it lately to get it to go anywhere. But then, maybe it's just me wanting my Vette. :L

 

[militant_x]

Im a novice, but it could be anything from a weak ignition component (wires, coil, sparkplugs, timing retarded etc), or it could be something in the head (warped, sticking valve etc) or it could be rings, it could be the computer or mas airflow (or are lt1s map?) or the throttle position sensor, dirty air filter, failing fuel pump etc I mean it goes on and on. So many things can cause an engine to lose power. It may not even be the engine... the list goes on.

Any codes? .. Just in 2nd and 3rd? How does it pull in first? I dont know how hard it is to run a compression check on an LT1...

trying to help,

-chris

 

[vettenick]

Pull your spark plugs to check the gap and their color. If they're OK, road test the car with a fuel pressure gauge.

Good luck!

 

[jedi]

Update

This is getting weird. I have been testing for different problems, and found that when accelerating between 30-45 in Overdrive I get the sluggish acceleration, but if I put it in drive I have no problems. Acceleration outside of 30-45 is fine, from a dead stop all the way up no problem but if I slow to 30-45 and then accelerate I get the slow porfomance and increased engine whine. Anyone got ideas? Dealer and Amaco are totally lost.
Jedi

 

[vettenick]

You should go back and check the basics...make sure that you igniton system is working properly, and that your fuel pressure is OK. It sounds like you're trying to accelerate when the transmission is in 4th gear. This will put a load on both the ignition system and fuel supply. If either system is not up to par, you will have problems.

 

[Robertwav1]

I really hate to ask this but...was the fuel filter changed? May not be the fix but take it out of the equation. I don't know how may miles are on the car but it may be due anyway.

 

[jmccloud]

...that when accelerating between 30-45 in Overdrive I get the sluggish acceleration, but if I put it in drive I have no problems....

Had three cars that did this, one of them was like riding a bucking bronco. The worst and best performing had one bad plug wire that was causing the engine to lug in overdrive. The third car had a burnt exhaust valve (compression test showed it right away).
Hope it's a plug wire.

 

[Daryllawman]

I had the same problem the other day.......I changed out the fuel filter and the pump......Now I am back to leaving the Rustangs back there somewhere.......

 

[jedi]

Just heard back from the dealer. Apperently this is a common thing with similar year vettes. They said the problem is that the car does not want to downshift at those speeds (which I am told is normal and there is no adjustment for it), so the load is increased until it gets fast enough to shift up to the next gear.

They recommended the same thing you guys did, new plug wires, and fuel filter, and a fuel injector cleaning. The plug wires and filter I will do myself this weekend. The fuel injector cleaning I am going to have them do, for around $350. Sound resonable to you guys? Thanks for all your help guys.
Jedi

 

[RedRagTop]

Between 30-45 in OD I have never realized steller acceleration. I run mine around town in D just to avoid the lug as it is normal in my mind to have low torque in high gear at low RPM...

 

[cntrhub]

"The fuel injector cleaning I am going to have them do, for around $350. Sound reasonable to you guys?" OUCH!! Does the car start right up and idle fairly smoothly? Is gas mileage about the same? If "yes" to both questions, I would for now......pass on the injector cleaning. I hate to see you spend that much for little, or no improvement.
I like vettenick's suggestions.

 

[jedi]

Too late they should be done soon......

 

[prepass]

cat. converter, fuel filter. Fuel filter first, cheaper

 

[vettenick]

Just curious....What is the dealer going to do for $350? If it's just to clean the injectors, it sounds a little high. Either way, I hope it fixes your problem.

Good luck!

 

[Rogue]

If you've been using premium fuel all this time from a reputable source, the fuel should already have "detergents" that keep your FI cleaned.

$350 to clean FI's is steep. You can buy all 8 FI nozzles for that price from MidAmerica I think.

 

[drcorvette]

Between 30-45 in OD I have never realized steller acceleration. I run mine around town in D just to avoid the lug as it is normal in my mind to have low torque in high gear at low RPM...

I agree 100%!!!!

 

[jedi]

Update

I got my Vette back yesterday and deffinitly noticed an improvement in acceleration and fuel economy. Fuel economy went up 2 points! Have new plug wires coming Thursday which should really improve it. Thanks for the help guys!
Jedi