Long story short. On my way to work this morning my 03 Neon Auto started blowing coolant out of overflow bottle. Trans started slipping, pulled into service plaza and checked. Trans fluid low, blowing what looks like trans fluid/coolant mix from overflow. Pulled 4 or 5 trans codes, don't have them on me right now. Is the cooler leaking a common problem? Don't have the car home yet. Am looking at worst case being radiator and trans toasted. Might get lucky and cut it off soon enough (fat chance with my luck). Anyone have experiance with this? Considering MTX swap after i get it home.

 

Hard to say if the transmission is toast without getting the contaminated fluid out and filling it up with new fluid and checking the operation.

Will wait for the codes though...

 

damn thats crazy, the transmission isnt connected with the coolant system is it?

 

im sorry but your tranni is probably shot. You need a new radiator and probably a new trans. If u look at side of radiator you will see 2 small steel lines attached. These carry transmission fluid bud. fluid in and out of a seperate radiator.its like a radiator within a radiator. The transmission radiator sprung a leak allowing tranni fluid to mix with antifreeze so you probably have a small crack on the outside of your tranni radiator on the inside(hard to explain)

you might get lucky if you didnt drive it too much so the tranni might be safe but you'll definitaly need a new radiator

 

AHHHH that makes sense, i drive a manual so i dont deal with anything like that, so the radiator accually is used to cool the tranny fluid also, but sounds like if your radiator has ruptured and allowed engine coolant to mix into the tranny with the tranny fluid its probably done some major damage... You may be lucky if you can just change the fluid and filter and make sure its pretty well clean, but youll still need to change the radiator.

 

I'm thinking the trans fluid pressure was more than coolant system pressure while driving. After it was shut off the coolant system pressure would force coolant back into the trans, as long as I don't run it like that (haven't had it towed home yet), I might be OK. Will probably bypass cooler and flush system just to check operation before I start rippin and tearin. Driving the Jeep 75 miles a day will give me incentive unless it magicaly gets a fuel mileage increase.

codes P0700 Trans. control system malfunction
P0734 Gear 4 incorrect ratio
P0846 Trans fluid pressure sensor/switch "B" circuit range/performance
P0871 ???
P0440 pending as always until it warms up outside and the CEL light will come on

Codes all sound like low fluid codes except P0700 which could be because of fluid pressure issues. Will have to see on that one. Any one know what 0871 is? not in the book with my code reader.

Oh, I have been a Heavy Truck Tecnician for 20 years, I should check my profile and see if thats in there. Was looking for personal experience on how fragile the trans and electronics are. I realize the explanation was for Neonftw87.

 

P0440-GENERAL EVAP SYSTEM FAILURE

When Monitored: Engine Running. Fuel Level greater than 12%. Ambient Temperature between 4°C and 32°C (39°F and 89°F)

Set Condition: The PCM does not see the NVLD switch close during the medium/large leak test. The PCM will then increase the vacuum supply to the EVAP system by increasing flow through the EVAP Purge valve. If the switch does not close with an increase in vacuum, an error is detected. Two Trip Fault.

POSSIBLE CAUSES
GOOD TRIP EQUAL TO ZERO
VISUAL AND PHYSICAL INSPECTION
EVAP PURGE SOLENOID VACUUM SUPPLY INSPECTION
EVAP PURGE SOLENOID STUCK CLOSED
NVLD SWITCH OPERATION
(Z1) GROUND CIRCUIT OPEN
NVLD ASSEMBLY
(K107) NVLD SWITCH SIGNAL CIRCUIT OPEN
EVAPORATIVE EMISSION LEAK DETECTION
PCM


P0700-TRANSMISSION CONTROL SYSTEM/READ TRANSMISSION DTCS ON THE DRBIII (MIL REQUEST)

This is an informational DTC letting you know that a DTC(s) is stored in the Transmission Control Module. Erase this DTC from the PCM after all Transmission DTC(s) have been repaired. Using the DRBIII, read the Transmission Controller DTC and refer to the Transmission Category and perform the appropriate symptom. PCM Diagnostic Information complete.


P0734-GEAR RATIO ERROR IN 4TH

When Monitored: The Transmission gear ratio is monitored continuously while the Transmission is in gear.

Set Condition: If the ratio of the Input RPM to the Output RPM does not match the
current gear ratio.

Theory of operation: The transmission system uses two speed sensors, one to measure input RPM and one to measure output RPM. These inputs are essential for proper transmission operation. Therefore, the integrity of this data is verified through the following checks:
1. When in gear, if the gear ratio does not compare to a known gear ratio, the corresponding in-gear trouble code is set (codes 50 through 54).
2. An excessive change in input or output speeds indicating signal intermittent will result in codes 56 and/or 57 being set.
3. After a PCM reset in neutral, observing erratic output and input speed sensor signals indicates a loss of the common speed sensors ground. This
sets a code 58.

Transmission Effects: The transmission will not go into Limp-in mode until three gear ratio error events occur in a given key start also the MIL will illuminate after 5 minutes of substituted operation. This allows for intermittent problems to correct themselves without opening the relay. However, if a gear ratio error develops, a code is always set, but if the condition corrects itself the transmission will continue without requiring the ignition key to be cycled on and off.

POSSIBLE CAUSES
> If code P0944(35) is also set, follow diagnostic procedure for code P0944(35) first
> Failed or slipping OD clutch - may also set code P0733(53)
> OD and Reverse inner and outer lip seal leakage (usually hard code)
> Sticky OD accumulator seals (intermittent)
> Worn reaction shaft support seal rings (hard code at heavy throttle)
> Broken OD/UD tapered snap ring - (hard code at heavy throttle)
> Failed or slipping 2/4 clutch - may also set code P0732(52)
> 2/4 seal leakage (intermittent)
> Sticky accumulator seals (intermittent)


P0846(22)-2/4 PRESSURE SWITCH SENSE CIRCUIT

When Monitored: Whenever the engine is running.

Set Condition: The DTC is set if one of the pressure switches are open or closed at the wrong time in a given gear .

Theory of operation: The Transmission system uses three pressure switches to monitor the fluid pressure in the LR, 2/4, and OD elements. The pressure switches are continuously monitored for the correct states in each gear as shown below.

Transmission Effects: If the 2/4 pressure switch is identified as closed in P or N, the code will immediately be set and normal operation will be allowed for that given key start. If the problem is identified for 3 successive key starts, the transmission will go into Limp-in mode. If the 2/4 pressure switch is identified as being closed in 1st or 3rd gear and was not identified as being closed in P or N, then 2nd gear or 4th gear will be substituted for 1st or 3rd gear depending on throttle angle and vehicle speed. A short period of time after the gear substitution, the transmission will return to normal operating mode. If the transmission is shifted back into 1st or 3rd gear through normal operation, and the 2/4 pressure switch remains closed, 2nd or 4th gear will be substituted briefly and then resume normal operation. If four gear substitutions occur in a given key start, the transmission will go into Limp-in mode. If the 2/4 pressure switch is open (indicating no 2/4 clutch pressure) in 2nd or 4th gear, the Transmission Control System sets code P0846(22) and continues with normal operation. The transmission will only go into Limp-in mode if a code P0706(28) is also present. If no 2/4 clutch pressure is present a gear ratio code P0732(52) or P0734(54) will be set and cause the limp-in condition.

POSSIBLE CAUSES
> If code P0944(35) is present, ignore code P0846(22) and perform code P0944 diagnostic procedures
> 2/4 pressure switch sense circuit open or shorted to ground between PCM and solenoid pack
> 2/4 pressure switch sense circuit shorted to battery
> Solenoid/Pressure Switch assembly
> Transmission overheated - Excessive regulator valve leakage in valve body causing high line pressure which results in 2/4 solenoid blow-off in 1st or 3rd gear. May require new valve body if it happens only when hot.
> Loose valve body bolts
> Plugged filter - internal transmission or torque converter failure
> PCM


P0871(21)-OD PRESSURE SWITCH SENSE CIRCUIT

When Monitored: Whenever the engine is running.

Set Condition: The DTC is set if one of the pressure switches are open or closed at the
wrong time in a given gear.

Theory of operation: The PCM uses three pressure switches to monitor the fluid pressure in the LR, 2/4, and OD clutch circuits. The pressure switches are continuously monitored for the correct states in each gear as shown below.

Transmission Effects: Normal operation will be experienced if no other codes are present. Transmission Control System will ignore the code. Limp-in condition will only occur if code P0871(21) is present with a code P0706(28).

POSSIBLE CAUSES
> If code P0944(35) is present, ignore code P0871(21) and perform code P0944 diagnostic procedures
> OD pressure switch sense circuit open or shorted to ground between PCM and solenoid pack
> OD pressure switch sense circuit shorted to battery
> Solenoid/Pressure Switch assembly
> Loose valve body bolts
> Plugged filter - internal transmission or torque converter failure
> PCM

 

a radiator and fluid is nothing compared to a tranni.
if your lucky then you can flush your transmission and it will be fine but if coolant got into any spots that you miss then owch.best of luck man

 

Thanks for the info darthroush. Maybe I'll get lucky and just need a good flush for the trans. and cooling system,don't need any balloon animal hoses poppin and cookin motor and/or trans. if I do indeed get lucky on this one. Hope to get it home tommorrow and at least drain out fluid from trans. I spent this afternoon pickin up Caravan for wife for now. I will update when I know more.

 

well when you drain the trani fluid you'll be able to see if alot of coolant got in it.let us know what you find.