Mitsubishi Forum - Mitsubishi Enthusiast Forums

Mitsubishi Forum - Mitsubishi Enthusiast Forums (https://mitsubishiforum.com/forum/)
-   1st Generation (https://mitsubishiforum.com/forum/1st-generation-62/)
-   -   My 93 1.8L eclipse has no acceleration and rough idle. Whats wrong? (https://mitsubishiforum.com/forum/1st-generation-62/my-93-1-8l-eclipse-has-no-acceleration-rough-idle-whats-wrong-26120/)

zncus 03-09-2008 09:55 AM

My 93 1.8L eclipse has no acceleration and rough idle. Whats wrong?
 
I have1993 1.8 liter Eclipse with an automatic transmission.I am experiencing three conditions/problems.

1) Rough idle when engine is cold and rough idle when engine is at operating temp.

2) Before engine is at operating temp, while accelerating out of cruising mode into passing mode, the tyranny down shifts well but in transition out of passing mode backinto cruising modethe tranny will up shift for a moment and then will rapidly down shift into D2 and then just as swiftly up shift back into D3.

3) After the engine reaches operating temp, the engine looses most of its power and acceleration. It barely has the power to accelerate over a 10 degree slope in the road, even if I manually down shift into D1.

Any idea on what is the cause of these symptoms???

Thanks
Scott

dsm1990gsx 03-09-2008 10:44 AM

RE: My 93 1.8L eclipse has no acceleration and rough idle. Whats wrong?
 
Is the car miss-firing? Check your plugs and wires along w/ the distributor cap and rotor.

zncus 03-09-2008 05:27 PM

RE: My 93 1.8L eclipse has no acceleration and rough idle. Whats wrong?
 
MISS-FIRING?? No miss-fire. Just no power.

jgbrules 03-09-2008 10:36 PM

RE: My 93 1.8L eclipse has no acceleration and rough idle. Whats wrong?
 
hello! sounds like you have several different problems.#1 your idle problem could be as simple as adjusting the idle speed. adjust screw on a 1.8 is on the linkage that the motor rides on. if it wont adjust you will have to replace it. those idle speed motors dont age very well. clean out the throttle body as well if you replace the motor.#2 sounds like to me the trans is on its way out. you should scan the TCM for codes, it could be a solenoid on the valve body, or even the tcm itself. if it has 5 or more codes in it most of them bieng1-2 non syncronus, or 2-3. trans is smoked. most of the time when the TCM goes bad a scanner cant access the system. it will give you a" cant communicate" message. when that happens the trans will be in limp mode or whats called fail safe mode. it will be stuck in 3rd gear. it will drive but wont shift and have NO POWER. sometimes a trans will be in the process of going bad and it might take a few shift intervals to set enough new codes before it goes into failsafe. meaning it might get to operating temp before the problem occurs. so this could also be relating to problem #3. the only other thing i can think of is the internal parts of the distributor are starting to go bad, usually heat accelerates the problem, so when it gets warm? you guessed it!! no power.the pick up coil is usually the culprit. i dont know if you can get that part from mitsubishi anymore. the aftermarket ones i have put in are a crap shoot. sometimes they work fine, and sometimes the car gets towed back in after a few weeks or months. go dealer if you can!! i would first start by scanning both the PCM&TCM for codes. that might give you a little direction. hope this helps!! keep us posted! greg....

zncus 03-11-2008 09:22 PM

RE: My 93 1.8L eclipse has no acceleration and rough idle. Whats wrong?
 
Thanks a lot Greg. Your really raised some great points. I think you are right. The problem is inthetranny. I will preform the checks you have recommended and tell you what the results are. It may take some time, I have very little time to work on the car.

Thanks again
Scott

zncus 03-16-2008 05:34 AM

RE: My 93 1.8L eclipse has no acceleration and rough idle. Whats wrong?
 
Hi Greg. Had some time to drive the car some moreand test the tranny. You are right, the tranny is not down shifting to 1st gear. That is the cause of the poor acceleration and loss of power.
When the car is cold, the tanny shifts through all three gears, 1st, 2nd and 3rd. But once the car warms up, it will not shift into 1st gear, either manually or automatically.

I tried to read the error codes on the Transmission Control Module with an analogue volt meter, (this is the technique recommended in an automotive manual called "Mitchell On Demand") . I connected the (+) prob of the meter to pin 10 and (-) prob of the meter to pin 12 of the data terminal. It read out at a constant value of approx 5 volts. I even tried to drive the car with the volt meter connected to the data terminal and the reading between pin 10 and 12 was a constant 5 volts. I even tried to cycle the ignition switch on-off, on-off and then on within 5 seconds, and the reading was still 5 volts, (when the ignition is off, the reading is 0 volts).
I did notice one other inconsistent thing about the tranny - With the ignition switch on, engine off, if I shift the tranny into reverse, I hear some type of actuator, or motor, in the tranny run for a couple of seconds and then stop. When I shift into D3, I hear the same thing, (small electric motor in the tranny will run for a couple of seconds and then shut off). When I shift to D2, I hear nothing. But when I shift to D1, I hear the motor run and it does not stop. It just keeps running. It seams like there is some type of electronic actuator/motor that shift the tranny through its gears and for some reason it can not find 1st gear and it keeps running. That may be completely incorrect but it is what makes sense to me at this time.
Could it be the Kick-down Servo? And if yes can it be adjusted, or replaced? If not the Kick-down Servo what else could it be?


Thanks
Scott
Email address - sksobi@netscape.com

jgbrules 03-17-2008 11:16 PM

RE: My 93 1.8L eclipse has no acceleration and rough idle. Whats wrong?
 
hey scott. the noises you hear are the shift solenoids inside the trans. depending what gear you put it in the appropriate solenoid will activate. sounds like a buzzing noise for about 2-5 seconds. thats normal. that solenoid lets fluid go through the valve body into the appropriate clutch pack. there are 4 solenoids.1-2, 2-3, low&reverse, and overdrive. scott, that volt meter method is very inacurate. as you found out it isnt worth it. you can go to auto zone or any parts house and buy a cheap hand held scanner that will read codes for you. and it will give you that cant communicate message i was talking about if the TCM is bad. if you have the extra money take it to any reputible shop and get it scanned for codes. cost you 40-50 bucks though. if you cant take it to the dealer, go to a place that specializes in imports. they have the proper scanners to plug up to that model. as for the kick down servo, all that does is adjust the band tightness on the kick down drum inside the trans. it might cure a slip for a little while, but its not gonna fix a trans in fail safe. another thing you can do if you can access the equipment is take pressure readings on the trans. there are ports on the main body of the trans that are properly labeled for each clutch pack. you will have to get a high pressure line with a proper fitting to screw it into the port, and a gauge that will read up to 200PSI. that mitchell on demand website should give you the specs on proper pressure. another good site is alldata.com. if the clutch packs do not have proper pressure the TCM will see that and put the trans in failsafe. also if the TCM is bad and doesnt do anything the trans also will automatically go into failsafe. my money is on the trans. 99 times out of 100 if a TCM goes bad, its bad. it wont work and then sometimes will. usually it shorts and burns a hole in the circuit board. no fixing that. PCM can do the same! those pressure readings will tell you if the trans needs overhauling or not. and scanning for codes will tell you if the TCM is bad. i hope this helps scott! keep me posted! greg....

zncus 03-20-2008 06:23 AM

RE: My 93 1.8L eclipse has no acceleration and rough idle. Whats wrong?
 
Thanks again Greg. I will take the car in to have it checked out. I will post the results.

Scott

nelsonedwin 08-06-2021 11:36 AM

can read codes w/o scanner
 
pretty sure can read codes with jumper with intermittent ability to cycle comp. then it will have some combination of dash lights that blink count them and write em down then go on line and look that code # up most all of them can be accessed in analog mode different makers may have different combos of them but i think that works the initializing could be cycling key or the jumper point switch im unsure of that think 3 or 4 times will activate it then off and back on and it should start blinking codes on dash pretty sure but i have been wrong before so i would do your own research and do what you think best


All times are GMT -5. The time now is 08:07 AM.


© 2024 MH Sub I, LLC dba Internet Brands