Hey guys. I just picked up a 2001 Neon as a project/investment for $300. The PO told me it had a blown trans. Upon doing a bit of reading and researching, it seems more likely that the TSS is bad.

Symptoms include: wont rev past 4k in neutral, or 3k in gear (limp mode?). It wont shift into third gear. The revs rise slower than they should- it sounds like the motor is under heavy load when I rev it in neutral. Also (probably unrelated) but the battery goes dead after sitting for a day. BRAND new battery.

The thing thats stumping me is, theres no check engine light. I would assume if the car was in limp mode, itd have a CEL. I'd like to be able to confirm my suspicions before I go out and spend $155 on a TSS. It seems to have most of the symptoms of this problem, but id really be kicking myself if i replaced the part and it didnt solve the problem. Can anyone offer any advice on the matter?

 

my suggestion is to get a real scanner and look at codes and DATA. see what the computer is seeing.

I never heard of a rev limit of 4k on neons. sounds like there's an engine/computer problem

are you dealing with a 41te overdrive trans?

 

I havent a clue. Its a 2001 Neon ES... 2.0 16v SOHC.

I only got it to rev to 4k once... usually it kinda tapers off at 3 grand, but i kept it pinned once just to see where itd rev to.

If it was throwing a code, wouldnt I have a CEL? Im new to domestic cars (this is my first), but on all my past cars, I could pull the codes either from the ECU itself, or by using a jumper wire to make the CEL flash the codes. Is there a way to do this on the neon?

 

IDK of any OBDII car (1996+) that allows using a jumper wire to make the MIL blink.

does the MIL come on when you turn on the key --- bulb check?

but with a chrysler product, you can cycle the key 3x to get it to blink. but i'd be connecting a real scanner to see what the computer sees for a problem. Neon's don't have a rev limiter at 3 or 4k!

 

They do if the computer is in limp mode. Im just confused why the computer would go into limp mode without throwing a check engine.

The check engine does come on when i initially turn the key- as do all of the dash lights. So I know the bulb is good.

Tell me more about "cycling the key 3x to get it to blink." Does this just mean, turn the key on, then off, then on, then off, then on? This will get the ecu to flash the codes? (ie, 2 long, 2 short = code 22?)

My OBD2 240sx has a two prong diagnostic port that, when jumpered together with a peice of speaker wire, will cause the ECU to flash the codes on the dash. Ive also worked on an OBD1 mitsubishi that did the same. Some cars have a bulb on the ecu itself that will flash the codes. Either way, ive never run into a car where the ONLY way to pull the codes was with an OBD2 scanner. Theres always another way to get them (on the cars ive worked on anyway).

Side note, is there a way to pop the trunk besides the clicker and key? Or is that it? No lever in the car?

I appreciate the help by the way.

 

since you have zero chrysler experience, what do you mean by "limp-in"?

that's a term chrysler guys use to describe transmission problems!!!

you can always take out the back seat to open the trunk or use a BFH. not all cars have remote trunk release lever. I know some Geo metro's do and some dont and some toyotas do and some dont, etc.

do a search for 'key dance' I read a lot of chrysler guys doing this to get the MIL to blink.

 

lol, not "limp-in." LIMP MODE. Limp mode for cars is like putting a computer into "safe mode." I would assume it retards the timing, richens the fuel, limits the revs to keep the engine in as safe of a condition as possible, because the computer recognizes something being wrong, and goes into limp mode to prevent further damage from occurring. All I need to know is- can a neon go into limp mode without throwing a check engine light?

If the answer is yes, how do I confirm that the trans shifter solenoid is bad?

If the answer is no, where do I go from here?

 

that's not a term used around chryslers. Limp-in is used to describe transmission failure only not engine related problems.

You have an engine related probem. You need a REAL scanner to read engine information. could even be someone worked on this car and screwed up cam/crank timing

 

Im not trying to be a dick, especially since Im the one here asking for help.. but I think you need to educate yourself before offering advice. Limp Mode is most definitely a term used for all fuel injected cars that utilize an ECU. Do a google search for "neon limp mode."

If you have never heard of limp mode before, I cant expect you to know why the ecu wouldnt throw a code while being in limp mode.

Taken from another website:


Nearly every system in your automobile is controlled by onboard computers these days, especially your engine and transmission functions.

'Fail Code' conditions, or 'Limp Mode', happens when the vehicle computer recognizes a problem in it's logic. When an expected signal value from a sensor is sent to the computer and is not within the computer's programmed specifications, 'secondary' programs are activated by the computer to strive to protect the transmission from any damage the improper sensor signal might cause to occur, be signaling, or contribute to.

In other words, the computer is always expecting certain signal values from certain sensors i.e. the temperature sensor, the speed sensor, the throttle position sensor or MAP sensor, etc. As long as these signals are what it would normally expect for the current operating conditions and are normal based on all the other signals it is receiving from other sensors, it acts normally and accordingly.

If the computer, all of a sudden, receives some crazy signal from one of the sensors that is out of the normal range expected from this sensor, it is programmed to go into 'emergency' or 'secondary' measures.

These emergency measures vary depending on the severity of the defective signal. All of this is preprogrammed into the computer's logic by the manufacturer. The manufacturer has decided that as long as a certain parameter of a particular signal is sent from a sensor to the computer, all is well. The manufacturer decided that if this signal is higher than their highest parameter or lower than their lowest parameter, something is wrong with that sensor and the computer should make someone aware of the situation and take action to try to 'save' the vehicle systems or powertrain.

What type of action does the vehicle's computer take?

Well, perhaps the computer will simply cause the 'check engine' light to come on. The signal variation wasn't severe or critical enough to indicate any mechanical failures but the vehicle's operator is made aware that he or she should have the vehicle checked out electronically to see if a minor sensor has broken down or is starting to deteriorate and send the odd irratic signal. This type of condition is commonly referred to as a 'soft code'. Normal functions are not affected but if the repair is not made, performance or fuel efficiencies might suffer. Perhaps the sensor only malfunctioned one time and all other times was fine. This might be an early warning of a sensor that is beginning to fail or maybe it's a matter as simple as a loose connector or connection.

But sometimes, the signal needed to perform all operations normally is so far out of specification that the computer has no choice but to go into a more critical 'survival' mode. With vehicle transmissions, when the computer detects an obvious, dangerous signal value of this sort it will cause the internal tranny-fluid-line-pressure to default to 'high pressure' (in order to protect clutches and bands). The computer also turns off the transmission's electronic shift solenoids which in turn causes the unit to default to a single gear only (usually second or third). All normal signals to vary and control line pressure are overridden and everything defaults to 'full on' so a hazardous 'slipping' condition within the clutch pack cannot occur easily. This theoretically (and practically) is so that the vehicle's driver can get the damaged vehicle to the next town for repairs.
This condition is commonly called 'Limp Mode' for this reason --- rather than being stranded, you're able to limp to the next town in either second or third gear, with full tranny line pressure being applied, so that the clutch guts won't slip on your trip in and your vehicle will move along slowly but steadily to a service center... hopefully.

So like I said- the vehicle is in LIMP mode, which is there to protect the car from incurring more damage. The car being in limp mode is what's causing my symptoms- but limp mode is not the problem itself. Something else is causing the car to go into limp mode. According to my research, there is a good chance it is the transmission shifter solenoid, but without a CEL to pull a code from, I have no way of verifying this. With the TSS being $155, itd be stupid to replace it without anything more than a hunch that its the problem. Crank timing is most certainly not the problem, as the car was running fine one day, and then went into limp mode.

So to reiterate- how could the car go into limp mode without throwing a check engine? How do I confirm what is causing me to go into limp mode without a code? Is there any way to test the TSS without replacing it?

 

neon's don't have a tss.

using a real scanner is what needs to be done inorder to determine what the pcm is seeing.

US made cars are very different than imports that you are an expert with.

you could have something like a plugged cat causing your problem

part of the difficulty with problem solving this is your connection between transmission and engine related problems.

lets ONLY look at the rpm issue and disregard the trans shifting.
Neon's do not have any rev limit that is 3-4K. if the motor isn't reving beyond that point, you probably have a mechanical problem such as plugged exhaust, cam timing off. these may not set a MIL. In order for the PCM to set MIL for bad CAT, it needs to see 2 trips of consecutive failures. unless you are making 'trips' to activate all monitors, you probably won't get a MIL illumination for this failure.

your statement about not being able to rev past 4k in park/neutral has nothing to do with the transmission what so ever. and being these cars have no TSS, your problem has nothing to do with transmission related components what so ever