thrashingcows

Thought I would post this up here...hope someone can help.

Got a call from my sister in-law this morning, seems her 02 PT cruiser tranny died last night. The car has 302K km's, and no tranny rebuild to their knowledge.

She was just driving, slowed down and almost came to a stop, then turned a corner and the tranny would not go into any gear but 1st. She said if she reved it up to the point where it "should" shift, that it seemed to just go into neutral? And would stay there, and not down shift when the road speed dropped.

She said she would then have to shut the ignition off. Put the tranny in park, then start it up and try again. Tried this numerous times and the same thing happened over and over.

Check engine light came on a few minutes after all this started happening. My brother is a car guy, so he told her to try a few thing. So She tried disconnecting the battery for 10+ minutes...to reset the computer, and check engine light. But the issues never changed.

Eventually they had to get it towed home. Unfortunately my access to a code reader has been hampered by my friend going on holidays. So I'm trying to find some advice by the knowledgeable people who frequent these boards.

j_martin

First thing is make sure it didn't just leak fluid. Might be too late, though.

thrashingcows

She checked the fluid right after this happened. Said it was down less then a quart. Topped it up and nothing changed.

I had her pull the quick codes off the dash with the 3x's ignition on/off. She told me there is P0700 and a P1684. I have done a little searching and reading and have found that these are,

P0700 - DTC (Diagnostic Trouble Code) which means that there are more codes stored in the TCM (Tranny Control module) and will require a scan tool to access them.

P1684 - Is a code that comes up if the battery has recently been disconnected. So not an issue.

thrashingcows

Alright my brother found a cheapy OBDII scanner and hooked it up this evening, he got additional codes.

P0720 - Output Speed Sensor Circuit malfunction
P0732 - 2nd Gear Ratio incorrect
P0733 - 3rd Gear Ratio incorrect

I'm going over tomorrow evening with the Snap-on scanner I can borrow and see if any additional codes come up.

He did have some additional info though. He took it for a test drive this evening. First time he's had a chance since this happened. Anyway he says when driving normally it will pull to about 1500-2000rpm then just seems to go into neutral. You have to stop, put it in park, then turn ignition off...wait a couple seconds...then turn everything back on and it will repeat.

But he did discover that if he put it in drive, then put the throttle to the floor the car would pull all the way to 6000rpm and then hit the Rev limiter and just sit there. He said it pulled hard with no noise, or slipping from the tranny. But as soon as he let off the throttle, at the high RPM's, it would go into neutral.

I've done a little research on-line and I'm hoping it's just the solenoid pack, and the in/out speed sensors that need replacing?

Thoughts?

RocknRick

Output Speed Sensor monitors the teeth on the Rear Carrier, if it is defective, then it won't communicate with the control solenoid. This will keep the transmission from shifting properly. If it was down a quart of ATF, I would find out where the leak is as well, check the oil pan, diff pan. With that many miles the RTV could of separated from the case and the pan. Hope this helps

thrashingcows

Thank you for your advice RocknRick....I appreciate it!!

I'm going to have my brother drop the pan and check it, and the filter for clutch debris. If it all looks good inside then we will probably just replace the solenoid pack, and the in/out speed sensors.

RocknRick

Hopefully no debris. I think you have an electronic issue, input/output speed sensor or the solenoid. If any one of those aren't working properly, you'll have shift issues. Check and clean the magnet in the pan while you have it off changing the filter. Make sure to get RTV in the right area of the pan when reinstalling. If you don't, the excess can get sucked into the filter and cause more headaches. Good Luck

Rampage1967

Check out the speed sensor circuit. Your trans is going into limp in (locked in second gear) as it is supposed to when the computer garbage data. The sensor may be the cause of the other two codes.

thrashingcows

OK went over to my brother's last night with the code reader. Same codes as before...except for a P0731 - 1st gear ratio incorrect. He had gone to the wreckers and picked up a used set of input/output sensors and installed them. Hoping for a quick, cheap fix...Nope! I cleared all the codes.

The car still had no reverse, and would only go into first. We had it up in the air and brought the RPM up to 3000rpm and speed about 30 km/h....never shifted. And we could both feel an "imbalance" in the tranny, through the shifter, and brake/throttle pedals. Ran the codes again after this...all were back again.

So I suggest we pull the pan and see what was happening. The magnet in the pan looked like a puffer fish, or a sea urchin! There were lots of shiny metal debris in the pan too. We cut open the filter and found aluminum shavings. So that pretty much seals the deal...tranny is toast!

Thank you to everyone who offered advice, and suggestions.

RocknRick

I wouldn't say it's toast yet. Everything stuck to the magnet means it was doing it's job collecting all the debris from gears meshing and so on. I would try changing the solenoid(notorious for failing) after all it's what controls the speed sensors, shifting etc. Are you 100% sure the input/output sensors are good? Solenoids are cheaper than a Tranny. My guess is the pan has never been dropped or the filter changed. What you saw in the pan is to be expected with that mileage and Tranny not serviced. It may be toast, but I'd try the solenoid before spending cash on Tranny. Let us know.

thrashingcows

My brother picked up a used tranny out of the wreckers for under $100. Out of a 06 Neon, with 68K km's. Thing looked almost new, and the filter and pan were pristine!! Swapped it in and works like a charm! Then the alternator would not charge. We worked on that for a couple days and finally had to run a new wire from the stud on the alternator to the battery. Seems there is a fusible link hidden somewhere in that heavy wiring circuit, and it is toast. So for now this will do the job.