The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support RTM Racing
Please Support ExtremePSI

1G Auto Tranny Shifting Way Too High / OD Slips

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

TermTrky

15+ Year Contributor
175
9
Aug 23, 2007
PNW, Washington
My 1G FWD Auto is having issues. Bought it slipping in OD. All I've done is trans filter + refill.
It was violently downshifting after a lot of throttle, not wanting to upshift, etc. I put in a new TPS and set to .63V at closed throttle. I drive it with OD off.

It downshifts OK now - still a little indecisive. It upshifts at way too high of an RPM. I have to let off the throttle a bit and let it upshift.

I used a cheapo Amazon TPS. It ohm'd out OK. Rebuild time ? Has been hard to find a used fwd auto tranny. At this point, I would jump on any working tranny for $500 or less if I could find one.
 
My 2g gsx does pretty much the same thing, and I too have to back off the throttle to try to get it to upshift. As far as I know, mine doesn't slip though, just upshifts too high. Plus my downshifts are a little sluggish. I bought it last month and still haven't had a chance to do a trans flush and filter change. (I'm converting to manual one day)
 
Try setting the TPS, at the sensor, to .53v. That is the FSM setting, and I was having auto issues, throwing a TPS code and don't have link in that car (which is the only one running now) so I replaced the TPS and set it like that. I don't know if it will help but it does put the TPS in a different position. Just what I had to do.
 
Ouch, that would help. That's what I get for not opening the FSM myself. Somebody posted .63V erroneously. I had really harsh downshifts - after flooring the accelerator to get it to downshift - with the old TPS. It would change resistance every time you set it back to closed throttle.

I went for a drive last night with OD on (just to check). It did OK. No slippage. It won't manually shift from 1st to 2nd with the shifter. It has to be in Drive, cruise up to 4-5k and then let off the throttle and it will engage 2nd. I did verify that it is not in limp mode.

Maybe a combo of failing end clutch (od) and improperly set TPS (high rpm upshift?)

No codes. Transmission fluid did not smell burnt when I got it, but it could have already been changed. Based on the lack of basic maintenance, I doubt he would have changed the fluid.
 
OD was non-existent on my cruise last night. It just won't make up its mind. I'm going to stop driving it (it's not my daily). Try IPT's end clutch kit - I have no idea if end clutch issues can inhibit other parts of the transmission. Maybe it simply lost so much clutch pack it began to damage the other clutch packs.
 
.63 is correct if you are using Link. The FSM says .49-.53 AT THE SENSOR so I used a wire probe and set mine at .53 (I checked voltage of my old TPS before removing it, it said .53). Limp gives you only 3rd and reverse. My sons Spyder had a OD issue, every now and then it would try to engage but not hold. I did a IPT end clutch kit on it and it had a tore ring seal allowing pressure to bleed off. After the IPT kit solved the OD problem I put a Translab 175 in the valve body and it hit strong and was fun. Sounds like you may need the end clutch repaired if it wont hold OD. Are all the gears this way?
 
Yeah. My sons Spyder was a 97. But awd is the same stuff and I believe the end clutch is the same but don't quote me.
 
Adjusted TPS to .5v closed throttle at TPS harness. Manually engaging 2nd with shifter - nothing there. Harsh shift from 1-2 when in Drive, won't always engage 2. Manually engaging 1st - then shifting to 2nd - nothing there. Doesn't always start out in 1st. Doesn't like to kick down. OD is gone. Transmission is gone. 2/4 band for sure. Going to skip IPT clutch kit and find another trans. Hard to find a turbo fwd auto trans. Just started driving this car this last week so I've been trying to pay attention to the transmission.
 
I'll have to ask my son if he has any.
 
I may go the same route as TermTrky and find another awd trans, but only as a means to have it rebuilt with all the proper/upgraded parts and then put it in and maybe eventually do the same to the current one and have a fresh backup trans since for now, I have no desire to race this car. Only plan to do minor upgrades to improve the suspension and handling, and engine/transmission response.
 
IPT (I think) has a great rebuild video! Looks really involved if you're also doing all bearings. I've found some 2G transmissions, but no 1G's. At this point I would pay to crate a transmission, I'm getting desperate. My trans shop quoted me $3.5K - $4.5K.
 
No doubt. With a lot of table space and a $20 clutch spring compressor looks like you could disassemble one and do a soft part rebuild! Considering it. Can only find ipt's $500 clutch pack kit. Wish there was a cheaper option for an experiment.
 
Bingo. I wonder if a soft part rebuild would fix it.
 

Attachments

  • Screenshot_20170915-231707.png
    Screenshot_20170915-231707.png
    210.4 KB · Views: 59
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top