I have a 91 R/T that won't shift. It seems as if it is stuck in limp mode. I cannot manually shift it and it takes off real slow like it is in third gear. Anybody had this problem?
Thanks,
Dan:dodge1:
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I have a 91 R/T that won't shift. It seems as if it is stuck in limp mode. I cannot manually shift it and it takes off real slow like it is in third gear. Anybody had this problem?
Thanks,
Dan:dodge1:
"like limp mode". perhaps it's actually in limp mode?
I'm with Steve on this one. Plug 'er in and see what it says.
Well hopefully I can get my hands on a TCU and see if this is my problem.
Ok, so I pulled the tcu and sent it out for repair. I picked up a used one from a guy locally who had a 91 R/T with about 130k. He said he had no issues with the trans. However, I had the ECU rebuilt and it runs fine, better even. The trans is still stuck in limp mode! WTF! How can I have another bad tcu? Anything else I should look at?
Thanks,
-Dan
it might actually be dying. excessive metal shavings in the pan?
Well, the kid I bought it from said he just had the trans flushed. The fluid is clean and it was waaaaaaaaay overfull! I draid about 3qts and it's still a lil over the hot mark...not too much 1/8". No shavings from I can see. I should be getting my rebuilt tcu back this week. If I still have the same problem I may have to pull the pan and see my nightmare!
kid could have flushed it to try and "cover up" whatever was wrong with it. can't say for certain though. i've heard many stories about kids doing neutral-drops with an ATX. i wouldn't put it past teenage dumbass.
What you could do before you throw more money at it is read out the diagnostic codes.
If you know how to read the ECU codes with a meter the transmission codes are very similar except that you ground pin 10 then connect the meter (-) to pin 12 and the meter (+) to pin 6. (the ECU codes are pin 1 )
The list of codes is long, post up what you get and I'll look it up.
(or you could download the manual from 3SX )
Well, he knew nothing about cars. He was a geek going to IIT for electrical engineering. He claims to get it from the second owners widow. He actually died and the cars sat or about eight years. He drove it twice from the north side of Chicago to the south side (IIT) twice and it got hot. He parked it and asked a friend what was wrong with it. When I looked at it,it started fine but leaked coolant out of both "O" rings. I did a full 60k and replaced all hoses, gaskets and such. I just assumed the trans was ok because I found a receipt for a trans flush. I then find a bad tcu with "No Good" writen on it! lol Oh I haven't had the wool pulled over me in years. I will be looking at all electrical connections tomorrow.
If at first you don't succeed, then you don't succeed the second time...try a third time and bam, it works! The third tcu fix my shifting problems. It shifts quite well actually. I tried to get the codes and it would not stop sweeping (the multimeter). So, according to the book it was another bad tcu. It's funny how I came across the third tcu. On my way to Sears to get another analog multimeter (old one took a huge SH!T), I drove past a guy I knew was parting out a 91 SL. I had thought he had junked it by now. He had the garage open and there it sat. A few phone calls, a deal with a mutual friend and I am up and running!
Now I have a bad front end vibration at 60mph+... OMG does it ever end???
are your wheels balanced? that could be a vibration problem.
If it just started happening out of the blue make sure you don't have snow/ice/crud packed into your wheels. Pretty common problem in the winter, see if a run through the car wash fixes it :)
Yeah I just checked the front-end and all is tight. This car has a hound from every town for tires! It's more then likely the tires out of balance. No snow packed in due to it being in the garage most of the winter so far.
Did you make sure the lugnuts are tight? Did you lose a wheel weight?
Well I hope my 750lb/tq impact gun gets them tight! lol I have only drove the car up and down the block as few times since I got it. I have my original wheels and tires from my 92 R/T TT that I am going to put on. The regular R/T wheels are ugly IMO. This should tell me if I have a problem or not.
Tightening wheels with an impact is a bad idea. Overtightening is a bad thing and you have no control over am impact.
Overtightening wheels can warp the rotors though, so even if the wheels are shit, its still important not to overtighten.
if it only happens ~60mph or higher, it's not loose lugs. you'd notice that at 5mph.
its got be out of balance , how old are the tires? i have had a lot of tires when they get mileage start to vibrate at speed, warped rotors is a old wives tale
"warped rotors" is bullcrap. they might be heat-treated due to excessive braking; but that would only produce vibration during stops--not at speed.
Rotors can be warped by overtightening the wheels. That is fact. The warped rotor by excessive braking is the wives tale.
And my comment about overtightening is a seperate comment from his vibration issue. I just noted its bad.
I don't know how old the tires are. The tread is awesome on all four. However, as I mentioned earlier I have a hound from every town! They are all the same size and I checked to see if any weights had popped off and all is good. I hate the R/T wheels! My wife wants me to hold off on putting new tires on my R/T TT wheels until spring. So, I guess I will just have them balanced to make sure.
It only vibrates at 60+mph...so my guess is the wheels/tires out of balance or a broken belt.
Make sure to change the caps in the working TCU if they are original or it won't be a working TCU for long.
Unlike the ECUs, when the 47uf cap by the voltage regulator pass transistor leaks there is a very good chance the regulator will fail and dump 12v on the 5v buss to all the chips blowing them.
^is the the genius whose advice i've been warned about?
No, the Steve you've been warned about is Steve68.
Yeah I plan on having the third tcu rebuilt after I get my other two back. The original one was in such bad repair no way a novice like me could ever touch it and reserect it.
I wouldn't say normally not repairable. I have fixed many of them but the odds are bad enough that I won't anymore.[/QUOTE]
Well your the first one I asked to fix my tcu. I have a guy out in Oregon that has been messing with it. He found a lot of bad parts on it once he stripped it clean. So, hopefully he can get that one and replace the caps on tcu #2 before I send him #3 for a caps replacement as well.