How to Fix a 2001 Chevrolet Impala
Repair Advice for Sluggish Chevy Impala with no Power
Your questions answered about a 2001 Chevy Impala that has no power.
This weekly Q&A session answers your questions about cars and trucks. This week explores a 2001 Chevy Impala that is very sluggish.
Question: Chevy Impala Has No Get Up And Go!
Hi: I have a 2001 Chevy Impala 3.4 liter V-6 with about 100,000 miles. The car has no power from 0 to 40 mph, from a stop or roll. Up to 35 to 40 mph the car gets there at its own speed. Gas pedal all the way down or part way down makes no difference, RPM increases like it should with the speed of the car, auto shift or manual shift does not change the time it takes to get from 0 to 40. After 40 mph until about 65 mph, hit the gas it down shifts or just takes off great, runs like it should. Car has had a tune-up, gas filter, air filter, and transmission tune-up. Engine does not miss, idles fine, transmission is not slipping, Check Engine Light does not come on (and it does work). I have no idea what to check or try next.
Thank You,
Kevin
Answer:
Well Kevin, there are any number of reasons for an engine with that many miles to be sluggish. Usually what happens is a general wandering out of specification due to normal engine wear. First thing to do is read Back To Basics and Engine Testing With A Vacuum Gauge. This will tell you what to look for as far as the basic air, fuel and engine. Most of the time following the procedures in the article will fix your problem. If not it gives us a foundation for further troubleshooting.
Assuming all the basics are in good order, you can look for another problem.
First thing to do is scan the computer for any codes that may give us a clue where to look. Then do a fuel pressure and volume test. The engine needs the proper fuel pressure, in this case fuel pressure should be Key On Engine Off 52 to 59 psi, and the proper volume of fuel, in this case greater than 2.25 liters per minute. If either one of out of specification it will cause the engine to be sluggish and hesitate.
Another thing would be partially clogged fuel injectors. With the engine running, take a long screwdriver and place the tip on the injector under the connector. Place your ear on the handle and you will hear the injector clicking. It should be a nice, sharp click. If it sounds dull or muffled the injectors need cleaning. Best way to have the injectors cleaned is by the Chevy Dealer. Additives will not clean them, only a professional cleaning system will do the job.
Also check the level the condition of the transmission fluid. Dirty/worn out transmission fluid and partially clogged transmission filter will also make the vehicle sluggish. If it hasn't been serviced in a while, drop the transmission pan and replace the transmission filter. Replace the transmission pan and fill with the proper transmission fluid. If in doubt get the transmission fluid from your Chevy Dealer. It may cost a bit more but you will be sure it's the correct fluid.
If all that fails then do a wet/dry compression test. The engine itself my just be tired and worn out and need some internal repairs to bring it back.
The 3.4 liter V-6 engine is also prone to eating intake manifold gaskets. See GM Intake Manifold Leaks for more on this.
That's all for this week. Feel free to browse the archives for past topics and other resources. And, as always, if you are stuck and need an immediate answer you can always call Vince on the phone.
