Do i need a fuel system cleaning/service?

Question

Hi, I have a 2003 Mitsubishi Galant, 84,000 miles. It had been performing just fine until last week when it stalled out on me when I pressed the accelerator. The repair shop fixed it and said the intake manifold had come loose allowing unmetered air to get in. Now the car has a rougher ride and they recommended I do the following services:

Transmission flush

Fuel system cleaning

Do I need to do these? Will either help improve the rougher ride I'm experiencing since it's been repaired? Shouldn't the repair have resulted in my car being at least as it was before it broke down?

Answer 1

It depends on how long the unfiltered air was getting sucked into the cylinder(s). Some dummies used to pull out their air filters to "get more horsepower" but this lets all of that sand and dirt get into the combustion cycle (cylinders) and as it passes the intake and or exhaust valves it sand blasts that perfect valve to cylinder head fit or the valve seat and lowers compression and scores the cylinder walls and so forth.

I'd just run a tank of higher octane gas in it one time and see if there's any driveability changes for the better.

But. before you do this, ask the repair guys if they disconnected the battery during service. This "zeros" out the computer and you will have to drive the car for several days before the computer adjusts the timing and it runs more like it used to. The timing is gradually adjusted as things like spark gap changes and the teeth on your timing gears and chain wear with age and so on. When the battery is disconnected at any time, the timing goes back to the original mechanical settings and it will take the computer time to readjust after the battery is reconnected and the car is driven for several days.

Good Luck!

Answer 2

sounds to me like all you need is to change the gas filter. it sounds like the filter is dirty and restricting the flow of fuel. i fully agree with mustang, do not, i repete do not have the tranny flushed, if you have any seals or gaskets that are weak, it could start them leaking. if your going to do anything, just change the tranny oil and filter, dont flush it!

Answer 3

"Is this the first time the Transmission has been Serviced?" Do the Flush if the fluid is burnt (Bad Smell), if not Fluid & Filter Change Only.

Oil change is Needed if the Intake Manifold did come loose "Durt in the Engine and Oil!" Fuel System Service including Fuel Filter.

They Did Replace/Change the Intake Manifold Gasket when they fixed it, Right? Might also need a Tune-Up "Timing Checked & Reset.

NOTE; Manifold Came loose? Replace Manifold Bolts and check Manifold for "Cracks!"

Answer 4

ok here is the deal. what they are calling a fuel system service is more than likely an air induction service. you have carbon that builds up in the intake and throttle body assemblies. when that tube allowed unmetered air into the induction system it brought dirt in there as well. this dirt can cause the valves not to seat completely and also can cake up on moving sensors like the idle air control valve and also can restrict airflow to the top half of the motor.  fuel c**p in the tank will only clean the fuel lines and the injectors. it will not clean the dirty intake and throttle body. i recommend doing and air induction cleaning not a fuel system cleaning.  as for the trans service. it is reccomended from mitsubishi at around 50-60k miles as the transmission fluid type is mitsubishi diamond highly friction modified transmission fluid. after this time interval the high friction polymers break down and the tranny has to work harder to shift. you change the filter in the trans every 30k miles and flush every 50-60k mi.  getting a pressure flush is bad on your trans but the machines that use the natrual fluid flow of the transmission to exchange the fluid is reccomended. this service is not a flush but a transmission fluid exchange though it is commonly called a flush. but they have to put the diamond fluid back in it otherwise damage will result. the trans flush is not going to resolve your issue though. the air induction will help and probably  resolve alot of your problem and changing the plugs as they have fouled due to the uncalibrated unmetered air causing excessive fuel to flow will help.

Answer 5

DO NOT do a transmission flush. That's like changing the engine oil and leaving the dirty filter in place. A lot of places push them but I'd shy away from them. I'd also get a second or third opinion before I'd do the fuel system cleaning. Don't tell the other shops what the first one said, just tell them how the car is acting and let them decide what's wrong and what needs to be done.

Answer 6

transmission flushing just ruins transmissions. Fuel system cleaning is just bull ****. add STP to the gas and change the gas filter.

I would clean ( not replace) the egr system and the MAF sensor.