I bought a used magna one month ago. This car is 1993/magna/TR/SE/2.6L/4cyl/Auto/sedan/210000km, I feel this car is good condition, I use this car one month and last several times I note the petrol consumpiton.
Sum to: about 700km---130Litres, At high petrol prices this is dreadful.

Please help me to reduce petrol consumpiton with feasible means, if need to fix the engine, please recommend about better mitsubshi service and the service price.

I live in Meadowbank, NSW

Thank you very much!

Have you had it serviced?
Thats the first thing i'd get done. Have the engine cleaned up and a tune couldn't hurt it. Auto service while you're there. Make sure they replace all fluids. New gaskets etc.

I bought a used magna one month ago. This car is 1993/magna/TR/SE/2.6L/4cyl/Auto/sedan/210000km, I feel this car is good condition, I use this car one month and last several times I note the petrol consumpiton.
Sum to: about 700km---130Litres, At high petrol prices this is dreadful.

Please help me to reduce petrol consumpiton with feasible means, if need to fix the engine, please recommend about better mitsubshi service and the service price.

I live in Meadowbank, NSW

Thank you very much!

Hello jingsun,

After your purchase, was the battery ever disonnected in order to perform work on the car?

If so, the ECU / ECM (car's computer) is now going through a re-lean process regarding your driving habbits. This takes a while for the ECU to "re-learn" and in this situation your gas milage/KM will suck. If so, your mileage/KM will get better. This would not inculde the many parts that would contribute to poor mileage/KM - O2 sensor, spark plugs, ISC, distributor cap and rotor, spark plug wires, fuel filters, etc.........

TG

Thank you for your response.

After purchasing, the dealer change a new battery, so the battery ever disonnected.

Later on my friend help me to change the oil and oil filters, But the other parts do not change
and the oil may leak.

I have some questions:

1. How long or how much distance the situation for the ECU to "re-learn" is?
2. Need I change O2 sensor, spark plugs, ISC, distributor cap and rotor, spark plug wires, fuel filters, etc.........?
3. If need change these parts, where should I go to? How much the price of changing is?
4. I do not understand: "Have the engine cleaned up and a tune couldn't hurt it. Auto service while you're there.", could you explain it for me?

Thank you very much!

Thank you for your response.

After purchasing, the dealer change a new battery, so the battery ever disonnected.

Later on my friend help me to change the oil and oil filters, But the other parts do not change
and the oil may leak.

I have some questions:

1. How long or how much distance the situation for the ECU to "re-learn" is?
2. Need I change O2 sensor, spark plugs, ISC, distributor cap and rotor, spark plug wires, fuel filters, etc.........?
3. If need change these parts, where should I go to? How much the price of changing is?
4. I do not understand: "Have the engine cleaned up and a tune couldn't hurt it. Auto service while you're there.", could you explain it for me?

Thank you very much!
3. Autobarn or even supercheap auto is a good place to get these parts, they're just filters and general service stuff. O2 sensor could be a problem, but i'd leave that one for last as they can be costly. But you should definately replace all your spark stuff (eg. plugs leads etc.).
4. Clean engine as in: Clean the throttle body, general clean up the engine, that way if you have any leaks or whatever you'll see them alot better. Clean sensors/plugs with metho, make sure theres minimal exposing wires (retape them or whatever). Check hoses to make sure none are decaying or starting to split. A tune is basically advancing or retarding the timing, though on the 2nd gens this may be automatic i'm not sure, but i think adjusting it might be an option, talk to a mechanic about that one. Get your automatic gearbox serviced or even just get the fluid flushed, who knows when (and if) it's been done. Do all this, couldn't hurt.

"COMPUTER RELEARN PROCEDURES
1993 Mitsubishi Diamante
GENERAL INFORMATION
Computer Relearn Procedures
All Models
* PLEASE READ THIS FIRST *
The following general procedures are to be used if driveability problems are encountered after power loss or battery has been disconnected. These procedures may provide an aid in eliminating these problems. To reduce the possibility of complaints, after any service which requires battery power to be disconnected, vehicle should be road tested.

COMPUTER RELEARN PROCEDURES
Vehicles equipped with engine or transmission computers may require a relearn procedure after vehicle battery is disconnected. Many vehicle computers memorize and store vehicle operation patterns for optimum driveability and performance. When vehicle battery is disconnected, this memory is lost. The computer will use default data until new data from each key start is stored. As computer memorizes vehicle operation for each new key start, driveability is restored. Vehicle computers may memorize vehicles operation patterns for 40 of more key starts. Customers often complain of driveability problems during relearn stage because vehicle acts differently then before being serviced. Depending on type and make of vehicle and how it is equipped, the following complaints (driveability problems) may exist:
* Harsh Or Poor Shift Quality
* Rough Or Unstable Idle
* Hesitation Or Stumble
* Rich Or Lean Running
* Poor Fuel Mileage
These symptoms and complaints should disappear after a number of drive cycles have been memorized. To reduce the possibility of complaints, after any service which requires battery power to be disconnected, vehicle should be road tested. If a specific relearn procedure is not available, the following procedure may be used:
Automatic Transmission
* Set parking brake, start engine in "P" or "N" position. Warm-up vehicle to normal operating temperature or until cooling fan cycles.
* Allow vehicle to idle for one minute in "N" position. Select "D" and allow engine to idle for one minute.
* Accelerate at normal throttle position (20-50%) until vehicle shifts into top gear.
* Cruise at light to medium throttle.
* Decelerate to a stop, allowing vehicle to downshift, and use brakes normally.
* Process may be repeated as necessary.
Manual Transmission
* Place transmission in Neutral position.
* Ensure emergency brake has been set and all accessories are turned off.
* Start engine and bring to normal operating temperature.
* Allow vehicle to idle in Neutral for one minute.
* Initial relearn is complete: process will be completed during normal driving.
Some manufacturers identify a specific relearn procedure which will help establish suitable driveability during relearn stage. These procedures are especially important if vehicle is equipped with and electronically controlled automatic transmission or transaxle. Always complete procedure before returning vehicle to customer."

AND

"PURPOSE

1989 - 1994 four cylinder engines equipped with an Idle Speed Control (ISC) system (the type which opens the throttle valve) have adaptive memory built into the Electronic Control Module (ECM). This memory accumulates information on how an individual vehicle operates and adjusts the vehicle's ECM programming for optimum driveablity. Adaptive memory resides in the ECM's Random Access Memory (RAM) and the information contained will be lost when power is not available to the ECM.

This bulletin explains:

1. If adaptive memory is lost, in some cases, the vehicle may idle roughly (too slow) or may not idle at all due to deposits on the throttle valve.

2. Use the Scan Tool (MUT/MUT II) to erase Diagnostic Trouble Codes. Do not disconnect the vehicle's battery.

3. Idle the vehicle for at least 10 minutes after the battery has been disconnected for any reason.

4. Do not assume that the ISC is inoperative if the vehicle won't idle or idles rough after the battery is disconnected.

5. If the vehicle will not idle after a battery is disconnected, clean the throttle plates as described in the appropriate vehicle's service manual.

ADAPTIVE MEMORY DETAILS

The Electronic Control Module (ECM) contains adaptive memory which remembers the vehicle's typical operating characteristics. One of the memory's functions is to remember the "normal" operating position of the ISC.

As a vehicle is operated, deposits build up inside the throttle body housing and on the throttle plates causing airflow to become slightly restricted. In these cases the ECM instructs the ISC to increase the opening of the throttle plate. The ECM learns that the vehicle requires a larger throttle opening to idle properly in its adaptive memory.

When battery voltage is removed from the ECM (i.e. battery is disconnected) this adaptive memory is lost. The ECM then does not know the vehicle needs a larger throttle opening to idle properly and responds with its basic factory (new vehicle) programming. Consequentially, the idle may become rough until the ECM re-adapts. Clearing the Diagnostic Trouble Codes with a Scan Tool does not affect adaptive memory.

In some cases the deposit build-up will restrict air flow so much that if battery power is lost (adaptive memory is lost) the vehicle will not idle afterwards. The solution is to clean the throttle body as specified in the appropriate service manual.

Technicians are advised not to disconnect the battery unnecessarily, especially when clearing diagnostic trouble codes from the ECM's memory.

SUMMARY

1. Use the scan tool to erase diagnostic codes, versus disconnecting the battery.

2. Whenever the battery is disconnected, allow the vehicle to idle for at least 10 minutes. This will allow the ECM to re-learn its adaptive memory.

3. If a vehicle will not idle after the battery has been disconnected, clean the throttle plate.

4. Do not assume that an ISC failure exists if the vehicle will not idle properly after the battery is disconnected."

TG