Hi everyone.

I am losing my mind trying to work this trans problem out.

1999 eclipse spyder, 2.4L, automatic trans.

one day, just left the house and get a 1/2 mile down the road, notice the car won't shift. It is stuck in 2nd, typically but has no reverse. Getting an error code of P1750, which is for a bad solenoid.

I get hold of a guy with solenoids but he talks me out of buying them saying he has loads of experience with these cars and it is something internal.

So, I rebuild the tranny. It needed it having a burnt up clutch pack and broken low/reverse spring.

so, all is together and installed and I am hacing the exact same problem.

so I try a different TMU... same thing.

so I try solenoids from another car.... same thing.

so I try pulse generators from another car... guess what? same thing.

nothing thus far has corrected the problem. wtf?

maybe I should mention that the only thing I did before the problem first occured was change trans fluid and filter... I just read on here that this can cause problems... what kind of problems???

any ideas are more than welcome. this is just driving me freaking crazy!!!

In case my description of the problem isn't clear, I have no reverse and only 2nd gear typically. I can shift into Low and then into second but it will shift hard.

it definately sounds electrical because the trans is going into limp mode. when you rebuilt the trans did you have the valve body cleaned at a machine shop? did you replace those solenoids?

well, I am told it is not limp mode because I have no reverse. I should have reverse.

I am guessing that there is some damage to my valve body that i can't see or thayt I don't realize.

Maybe swapping it with another can show me through process of elimination.

as for electrical, there is virtually nothing I haven't changed. even though I did so with used parts, the problem is EXACTLY the same.

i have the identical problem. p1750 solenoid code. the car isn't really stuck in safe mode. but it does shift very erraticaly. with me it started with when i shifted into OD and the trans seemed to slip. i turned off OD and drove home. the next morning i went to try it and had no reverse. it does run in a few gears. but has really strange shift points. sometimes to redline. i put in a shift kit and new solenoids. i also did a filter and fluid change. and rebuilt the end clutch. no luck didn't change anything. turns out that one of the fluid veins poked thru to another one causing fluid to go the wrong way thru the valve body. i haven't fixed it yet. i am going to try and weld it. but i will let you know if it works. if not. i need a new valve body. oh i also replaced the pulse generators.

Ah ha! so it's probably the valve body with you guys... the only thing that wasn't changed! lol

Gotta love how that works out....

God I love my 5-speed....

It does seem like we have very similar problems.....

However, I did swap out the valve body with no improvement. Although, the replacement valve body is used and I suppose there is always the possibility of it having the same problem. I've had the kind of luck in the past.

Maybe I have a similar problem in the trans housing somewhere.

I am getting ready to pull this thing out again.

I don't mind working on the tranny, it's just the in and out of the car thing to test it that really sucks.

i will be working on mine soon. i am going to try and figure out a way of fixing it without replacing it. hopefully i can manage something. i'll keep you posted. let you know if it was my problem. good luck on figureing yours out. keep us posted if you figure out the cure.

the way i look at it. it either has to be the solenoids or the valve body. if the valve body has a problem it could appear as a bad solenoid if the fluid is not going where it is supposed to. or a solenoid is actually not working. i know IPT has rebuilt performance valve bodies in the $500-$600 range. that may be another option for you. i also found a place online that has valve bodies around $150 and it seems like they do a lot of testing on them to be sure they are working properly.

www.sunbeltvalvebodies.com

I am told that a solenoid would never cause "no reverse"... however, I do agree that a faulty valve body could casue fluid to flow incorrectly and give a solenoid error.

It also makes sense that I could have bought another used valve body with the same wear problem.

I suppose giving that a good look would be worth the effort instead of pulling out the transmission.

the A and B solenoids are on and off at different times in different gears. if one of the solenoids wasn't working properly i could definately see you not having reverse. and also screwing up different gears. making shifting very erratic. if the A solenoid wasn't working then when it is supposed A on and B off. it would show as BOTH off. which would possibly activate a different gear. although i do think that the valve body would definately be more probable.

the solenoids have nothing to do with reverse.

ok the post prior to my last post you say that you were "told" that solenoids would never cause no reverse. then after i make my post you come back on here and say "the solenoids have nothing to do with reverse". can you back this statement up? is the only proof you have that someone "told you this". if you know someone with another mitsubishi that the trans works. go disconect the solenoids and try and put it into reverse. my bet is that it won't shift into reverse. when i shift my vehicle into reverse i can hear the shift solenoids working. if they are not working then i do believe it is possible that your reverse would not engage. to come on here and say that the solenoids have nothing to do with reverse just because someone told you this does a disservice to everyone on here. because some people will take your statement as fact even though it is not. until you are sure of your statement. you should not come on here and state it as a FACT. i take most of the things said on these sites with a grain of salt. because so many people think they know so much about cars. you can usually tell the people who know what they are talking about because they give explanations that make sense. they don't just say that someone told them that solenoids have nothing to do with reverse. you can go to five people who think they know what they are talking about when it comes to cars. 2 of them will tell you that solenoids have nothing to do with reverse. the other 2 will tell you solenoids do have something to do with shifting into reverse. and the last guy who thinks he knows about cars will say "solenoid, what is that?" so these sites are good to get ideas but i wouldn't take to much as fact. if you do then you will most likely overlook your problem.

in this statement you say you agree that a faulty valve body could cause fluid to flow incorrectly and give a solenoid error.

well is it not also possible that the solenoids which control the flow in a transmission, one could go bad and cause no flow to open or close a valve in the transmission that controls reverse. causing a "solenoid error"

i found this on a website. it has to do with Cadillac. but makes the point of solenoids and reverse. i also posted the entire article at the bottom if you would like to read what the engineers at cadillac have to say about their problem of no reverse having to do with a solenoid in the transmission


No Reverse engagement. Owners of 2003 CTS models with the 5L-40E transaxle may complain of a no-Reverse situation. According to Cadillac powertrain engineers, the problem may or may not he accompanied by an illuminated MIL, with DTC P0722 stored in computer memory if the light is on. An internal short in the pulse-width-modulated TCC solenoid could be the root cause of the no-engagement complaint.


http://findarticles.com/p/articles/mi_qa3828/is_/ai_n9363215

Ryan, with all due respect and my apologies for the short answer previously, with the Mitsubishi, a bad solenoid will not cause a condition of no reverse. Reverse is controlled by the manual valve alone. The manual valve is a mechanical valve that connects directly to the shift linkage. When a Mistubishi transmission goes into failsafe or limp mode, it will have reverse and second or third gear only.... this means that even under a catastrophic electrical control situation, you will have those gears.

Now, as for written proof, I suppose I could point you to this manual for specific information on my series as well as a couple others. For conditions of no reverse, solenoids are not a cause. http://www.lilevo.com/mirage/89-92%20Colt%...0.PDF/atoh2.pdf

I've also dealt with one transmission repair shop and one mitsubishi mechanic thus far and both have confirmed that a solenoid would have nothing to do, at least in the case of this transmission, with a condition of no reverse. As for your cadillac example, all I can say is that it is not a mitsubishi and I'll go a step further in saying that it is probably the exception as far as transmissions go.

To address the concept of a faulty valve body giving the solenoid code, it is a situation of effect, not cause. IF the VB were faulty and fuid allowed to escape which caused the no reverse and that fluid were now traveling to the channel of one solenoid it would also give the reading of a bad solenoid or solenoid malfunction, perhaps.

maybe we have a clogged trans cooler. not allowing enough flow in the transmission or a bad pump or going bad. have you checked your pressure in your trans. the thing that makes no sense with my trans is that when i shifted in OD it started to slip. i see no reason why this would cause me to lose reverse. doesn't make much sense.