Acceleration Issue
paintedalley
12-09-2003, 07:56 AM
I have a 94 Galant 2.4 SOHC with an acceleration problem, I have very little power when taking off for about 6 to 10 seconds, no matter how much pedal pressure you use, after 6 to 10 seconds the car bolts off just about pushing your head into the seat, once past the first delay and at cruising speed the car runs great and I can accelerate to a degree to pass another car, I do have a passing gear. This problem is always at initial acceleration; weather the car has been driven all day or just started in the morning. Just replaced the Distributor last week, but this was a problem before than. Usually max speed starting off even if you floor the pedal is 15 to 25 mph for that 6 to 10 sec, and don’t even think of pulling out into traffic unless it’s totally clear for a ways !!
FORGOT to ad this: there are no codes showing and this car has been put on the computer with nothing showing up.
FORGOT to ad this: there are no codes showing and this car has been put on the computer with nothing showing up.
gmech
12-14-2003, 03:35 AM
- here's a few suggestions, listed in order of ease and costs and are based on personal experience - however, since results may vary... use at your discretion.
1. confirm the vehicle is starting out in 1st gear by manually starting out in L (LOW) and then manually upshifting each gear while counting the upshifts.
2. avoid using fuel grades with an excessively high driveability index (DI). DI is a measure of gasoline volatility, a tendency to vaporize completely, which is characteristic of 91 or higher octane fuels. Lower compression engines are designed to operate using 87 or 89 octane fuel and as a result, performance can be impacted if higher octane fuels are used.
3. perform the next step twice before moving to step 4. Run tank near empty and then fill up with 87 octane from highly reputable gas station. Also, add a bottle of fuel dryer and fuel injector cleaner.
4. if problem continues, perform an individual cylinder peformance test as follows: with engine running, simply lift each spark plug wire at a time from the ignition coil using insulated spark plug removal or equivalent pliers. Note, the RPM drop should be the same for all cylinders (between 200 and 300 RPMS). Little or no engine RPM drop may indicate faulty plug, low compression or faulty injector.
4b. if RPM drop is neglible for any particular cylinder, first inspect the plug and plug gap. If visually good, swap with plug from another cylinder to see if the problem moves, otherwise correct gap or replace/clean plug.
4c. if necessary perform a cylinder compression test. Minimum compression pressures at engine cranking speed is 157 psi. Difference between cylinders should not exceed 14 psi.
4c-1. if compression is lower in one or more cylinder perform a wet (oil) cylinder test. if compression improves after wet test, either compression rings are misaligned, worn or cylinder exceeds tolerance and engine may require repair.
4d. if a particular cylinder performance remains negligible following spark plug/compression operability, clean or replace fuel injector on questionable cylinder.
5. take vehicle to reputable service center for further diagnosis.
1. confirm the vehicle is starting out in 1st gear by manually starting out in L (LOW) and then manually upshifting each gear while counting the upshifts.
2. avoid using fuel grades with an excessively high driveability index (DI). DI is a measure of gasoline volatility, a tendency to vaporize completely, which is characteristic of 91 or higher octane fuels. Lower compression engines are designed to operate using 87 or 89 octane fuel and as a result, performance can be impacted if higher octane fuels are used.
3. perform the next step twice before moving to step 4. Run tank near empty and then fill up with 87 octane from highly reputable gas station. Also, add a bottle of fuel dryer and fuel injector cleaner.
4. if problem continues, perform an individual cylinder peformance test as follows: with engine running, simply lift each spark plug wire at a time from the ignition coil using insulated spark plug removal or equivalent pliers. Note, the RPM drop should be the same for all cylinders (between 200 and 300 RPMS). Little or no engine RPM drop may indicate faulty plug, low compression or faulty injector.
4b. if RPM drop is neglible for any particular cylinder, first inspect the plug and plug gap. If visually good, swap with plug from another cylinder to see if the problem moves, otherwise correct gap or replace/clean plug.
4c. if necessary perform a cylinder compression test. Minimum compression pressures at engine cranking speed is 157 psi. Difference between cylinders should not exceed 14 psi.
4c-1. if compression is lower in one or more cylinder perform a wet (oil) cylinder test. if compression improves after wet test, either compression rings are misaligned, worn or cylinder exceeds tolerance and engine may require repair.
4d. if a particular cylinder performance remains negligible following spark plug/compression operability, clean or replace fuel injector on questionable cylinder.
5. take vehicle to reputable service center for further diagnosis.
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