limp mode [ive searched]

[TSiFIRSTGEN]

Okay. i have a 92 TSI FWD A/T

:/

and i bought it and its in limp mode.
ive never driven it out of limp mode so i dont know exactly how beastly these cars are.

the solenoids have been replaced and the TCU is a rebuilt one. so now im out of ideas of what it could be.

i dont have a thing to check the error codes yet but im gonna get one. in the mean time does anyone have any ideas?

how often does contact cleaner acctually help?

just wonderin. thanks.

 

[420a-t]

blown intercooler pipe? bad o2 sensor?

 

[nightspeed87]

limp mode sounds like a volkswagen term,
id say maybe its just running bad or pulling timing, or boost leaks, which really just
amounts to running bad.

 

[xioca]

It sounds like he may be refering to A/T Limp mode. If that is the case there maybe be internal problems with your transmission. Have you tried to reset it by unhooking the battery for 5 minutes?

 

[twiztedgsx]

i haven't heard of too many dsm's goin into limp mode, i've heard of a lot of turbo'd hondas that do this...but he's right, it sounds like it has something to do with the A/T. try goin to an autoparts store (one with the right diagnostic hookup for the car) and have them clear the codes that are listed. usually that takes care of the problem for the time being, but start looking for the cause of why its going into limp mode...clearing the codes only temporarily solves the problem.

 

[freshlane]

VSS? Vehicle Speed Sensor? Happens in 2gs when the sensor goes bad. Hope that helps

 

[UKNOWHO]

ihave them clear the codes that are listed. usually that takes care of the problem for the time being

if ## car is a 92 you dont use a scanner to clear the codes u disconnect the battery and wait x amount of time then reconnect try that and if the code come back then u def. gonna need a scanner or... if you go to vfaq.com there is a step by step tutorial on how to pull the code with a multimeter using the diagnostic port

 

[TSiFIRSTGEN]

alright so i talked to the guy i bought the car from.


he replaced the ECU ... not the TCU.




ugh. dissapointment

so now im in search of a TCU. anyone know of where i can get one without paying 250+ dollars?

thanks.

haha im really excited to feel the true power of this vehicle

 

[TSiFIRSTGEN]

Been researching.


would converting to MT be better?


im leaning towards switching because the swap is easier to get than getting a new TCU.

 

[DJYoshaBYD]

Flywheel, clutch, pedals, master cylinder, slave cylinder, transmission, axles, motor mount.. thats what you will need to turn it to a five speed... OO yeah... Shifter, shift cables... Thats alot more work than you think

 

[freshlane]

did you even check the speed sensor?

 

[player69x]

When your car goes into limp mode its usually internal problem with the transmission. It can also be the speed sensor, tcu,selonoids, your transmission cooler among other things. But first you should change your tcu and retrace all the wires on your transmission and make sure non of them are crimped or touching.

 

[player69x]

Been researching.


would converting to MT be better?


im leaning towards switching because the swap is easier to get than getting a new TCU.

Converting to manual transmission would cost more than your car is worth. if your going to do that just look for a manual tsi and buy it.

 

[TheMadCheshire]

i disagree with the above statement that it'd cost more than the car is worth. I am currently collecting parts to swap my a/t to a m/t. The fact that I have a FWD is mostly why it is not going to be that much. All in all it's going to run about 500 all said and done.
Limp mode is caused by the TCU finding an internal problem with the transmission. The idea of limp mode is to provide a way home or to a mechanic and limit the damage to the transmission and not leave you totally stranded. You really need to get the codes from the TCU to find out why it is going into limp mode.
Here is the link on how to pull the codes.
I'd personally pull the codes and then decide if it is internal transmission work or just some circuit problems. From the research I've done real fast, it seems a lot of open circuit codes have popped up for other a/t drivers on the board.
Goodluck and keep us posted.

 

[player69x]

Where did you get Flywheel, clutch, shifter,shifter cables master cylinder, slave cylinder, transmission, axles, motor mount, plus install for 500 dollars let me know so i can convert my car to stick.

 

[Gs Dewd]

Okay what do you mean by limp mode? Tells us exactually what the car is doing. As in after starting the car and driving it drops straight into third gear. The tcu resets itself everytime you turn the car off. You need to have the codes pulled ,it could be cheaper just to shell out the $250 @ Napa yes Napa they can get the tcu.

 

[DSMboostin15]

Have you already opened up the TCU to see if the capacitors have leaked out onto the board? This happened to me with my 1.8. I changed out the TCU with a junk yard unit and it ran fine. And to everyone who is wondering, "limp mode" on an A/T means that the car will not shift out of 3rd gear with the exception of reverse. It can be a PITA when it goes because the car will be even slower.

 

[toybreaker]

One of the best ways to approach this kind of problem is logically, and one step at a time. When the problem could be mechanical or electrical, or a combination of both, it's easy to get overwhelmed and frustrated, so a calm, measured approach will usually yield the best results.

A good place to start would be a thorough check of the fluid. Wipe some a clean white paper towel. Are there sparklies? Does it leave a red residue on the rag, or is it more blackish? Does it smell all burnt?

Next, how's the level? It's kind of a pita to correctly check the fluid level. The best way I've found to do this is to drive a ~ few miles first, pull over on a good level spot, away from traffic, leave the engine running, firmly set the handbrake, run the shifter thru all the gears, pausing in each range, then go back to neutral, pop the hood and pull the stick, wipe it off, and then re-insert it. Pull the stick out, immediately turn it sideways (so it's level, and the fluid won't run down) and check the fluid left on the stick. It should be at, or very near the full,hot line.

It can be frustrating to try and get an accurate, repeatable fluid level reading, but it's worth the effort. Too much, or too little fluid will drastically alter the performance of an automatic tranny!!!!

I would also look at the wiring harnesses/connectors to the tranny (located in the right front, below the aircan/mas, above the tranny.) Many times these connectors can get damaged during an engine/tranny swap. They can also get covered with coolant leakage from the overflow bottle, and corrosion on the connector pins can begin to cause problems.

A quick visual inspection of the tcu may be a good next step. It's located on top of the tranny tunnel, all the way up front, towards the firewall. Inspect the caps for bulging/leakage/goo on the board. If it smells fishy 'ish, that's a bad sign.

A very good idea of where to go next can come from looking at the data stream from the tcu. The snap-on mt2500 scanner will read it. Almost every shop will have one, and if you know someone in the business, you should be able to get the hook up. (may I suggest you bring some beer? )

It plugs into the diagnostic port, just like a datalogger, and will allow you to retrieve transmission code information as well as the tcu data stream.

First, are there any codes?

Address those first.

After the codes are repaired, you're ready for a test drive with the scanner hooked up. (have someone else drive, , it's hard to try and read the data stream and avoid wayward buicks at the same time! )

I would suggest you look at the battery voltage carefully. If there's a cap issue in the tcu, you will often get a flakly/erroneous reading, especially on a test drive, when the tcu is trying to actuate solenoids, etc.

The two tranny pulse generators, "a" and "b" are mission critical items. They see the rotational speed of the input and output shafts inside the tranny. The tcu uses these to make decisions about which gear to be in. (In addition, the tcu uses this information to determine the health/holding power of the bands and cluches inside the tranny.) A fault in either of these circuits, (or the clutches/bands) will cause the symptoms you describe.

Check the vss against your speedo.

Sweep the throttle and watch the tps signal. The tcu uses this to determine load, and therefore, shift points.

Good luck, and I think some time put in on checking the basics will get you headed in the right direction.

The first time you brake/boost/launch will make it all wothwhile!