More transmission problems

[Jachenbach]

Hello again,
Last October I shared with the group my 92 525 wagon displayed the tran prog error. I changed the oil, cleaned the valve body and learned that what I thought was water intrusion was actually condensation caused by a poor vent design.

For the last 15K everything was fine. Last night hard shifts followed by almost stalling in idle. No error codes. Could this be a torque converter or the last breath of the transmission?

[genphreak]

Did you clean/unclog the vent orifice at the rear/top? These block commonly on many cars, bimmers no exception.

[Jachenbach]

I will try, is it worth changing oil, cleaning valve body, changing filter? What are the signs for torque converter troubles?

[whiskychaser]

Sounds like your ATF may be running hot or you have a pressure issue. Maybe check out this article?:
http://www.transtec.com/downloads/rebuilder_news/2nd_q95r-n.pdf

[Jachenbach]

I have left the car idle for the past three weeks now I get the trans prog error message and the engine turns over but does not start. Could the two be related?

[632 Regal]

Check the battery voltage, it wont start if it is low don't matter if it turns over or not.

[Jachenbach]

I will today let's hope that is the problem

[genphreak]

Bad battery is a common cause of airbag and auto trans errors on M50 e34s.

And system voltage dropping under 12V means ECU stops firing the injectors or the spark. Of course voltage typically drops lowest once it has cranked for a bit, so when the battery is bad this happens pretty fast. As the car seldom fires on the first crank, a poor battery will cause a persistent no start condition- even after charging. I've tried to get what I thought was a good battery charged back in service but it turned out to have died early due to shorts in the touring trunk wiring causing boot or doors open condition (This keeps a relay or two energized and increasing battery drain from <50mA to well over 150mA. Over a year or this it took a toll on the battery (lead acid batteries don't like being discharged regularly)

All that said, IIRC an e34 won't crank if the battery is below 12V when at the time you turn the key.

[632 Regal]

All that said, IIRC an e34 won't crank if the battery is below 12V when at the time you turn the key.

It will crank all day long, just wont fire.

I have a rather long story about an E31 I used to own.... wasn't the battery(s).

[genphreak]

Ah yes, true indeed. I was reflecting on cars equipped with the later EWS or DWA (all '95 e34 and most e32): I think EWS stops cranking as well as fuel and spark, depending on what triggers or fails. Prior models do not exhibit this behaviour/'have this feature'

[632 Regal]

Not sure of the dates but the anti theft deal is a bit complicated and ads to the confusion factor. If it has anti theft and it cranks and don't start I would definitely look into cutting the umbilical chord. Don't hurt anything unless you cut the wrong one. Be better if one pulls a plug and visually checks spark, mine would only spark at the shut off of the key when done. Very confusing since it had spark it should start I thought... 5 months of thousands of dollars until I cut the chord, turn key and fine.

[Jachenbach]

So many thanks to everyone, charged the battery overnight and it started right up without trans code! Now I have to understand where my electrical problem is (agree tailgate most probable source or maybe a loose belt?) could this have been the original problem with car not shifting or am I wishing for too much

thank you again,

jim

[Jachenbach]

Remember me? After rewriting the tailgate harness and charging the battery the wagon started up and ran fine for about 15 miles than the trans prog popped back up. I bit the bullet and am waiting for a manual transmission to be available locally. Problem is now car will not start, trams prof shows on indicator, battery fully charged and I am getting fuel, no spark.Any suggestions? Thanks

[Rustam]

There is probably a simple test for stall speed that one can perform. If the stall speed is proper then the converter is ok. Please look into this.

[Rustam]

You should check all available sensors (Crank position, cam position, and others). A badly connected/functioning (1)Fuel Pump Relay or (2)Main Relay can give "trans prog". I had this problem with a fuel pump relay. Check these as well.

Also check Throttle Position Sensor, and the Shifter Range Switch. Ask Shogun for mirrored link to my website, it shows how to check the switch.

Also is trans fluid filled up properly? If it has hard time reaching the pump there will be low pressure and shifting problems, as well as trans prog. Was anything done to the transmission prior to the maintenance mentioned in the title post?

[632 Regal]

Back to basics, as i mentioned earlier... Does the car have an alarm box.under the rear seat?

[Jachenbach]

I looked, no alarm box could it be in a different place because it's a touring model?

[whiskychaser]

Read the codes in the EGS module. That will point you to the source of the transprog message.

When you say you have fuel do you mean a. the pump runs when you crank? b. Pump runs and you have the correct fuel pressure? c. You have a+b but the injectors are not firing. d. You have a+b, the injectors are firing but you just don't have a spark?

[shogun]

the trans prog popped back up. I bit the bullet and am waiting for a manual transmission to be available locally
Trans program does not mean the trans is defective, do not waste money for a manual transmission. Trans program simply means there is something wrong with engine, brakes, ABS etc and that causes the system to go into trans failsave program to protect the transmission from further damage.

[632 Regal]

I looked, no alarm box could it be in a different place because it's a touring model?



Good question. I don't know where it would be in the touring. It sounds like it could be a false alarm issue until you can confirm if you have it or not.

Post 15 would be what to do if you confirm no alarm.

Checked realoem and there is no indication of where the unit would be. From a quick search some mention it under the rear seat and others say behind the glovebox. No indication of date of manufacture.

[Jachenbach]

Ok this is really getting to me, I do not have a code reader but I did something that will have everybody yelling at me. In addition to my 92 I have a 1990 735i that is in great shape and runs really well. I swapped the fuel pump relay, system (main) relay and no change on the wagon, and the 735 still runs well. I got another DME control module (a 402 because the wagon is a non vanos) and the wagon still doesn't start. I charged the battery overnight still nothing. Is there a way to read the codes without a reader.

[Jachenbach]

I still have the problem of the car not starting, and I wonder if the trans prog is not the issue but a symptom of an unrelated issue. If I disconnect the battery for a few days shouldn't the error message disappear?

[632 Regal]

Without rereading this thread have you tried the stomp test? Disconnecting the battery will reset the computer, the codes should still be in memory for a code reader, stomp test.

[Jachenbach]

Regal,

just tried stomp test no joy maybe because this is a transmission error not engine?

[whiskychaser]

Regal,

just tried stomp test no joy maybe because this is a transmission error not engine?

I suggest the EGS error is a symptom and not the problem. Have you checked for spark and that the injectors are firing? Power to the DME and EGS comes down the same route. If that fails, the DME cannot warn you but the EGS can - it gives you a transprog message.

[632 Regal]

Regal,

just tried stomp test no joy maybe because this is a transmission error not engine?

I was referring to your "unrelated issue". ^ Whisky makes a good point.

[genphreak]

0. It did start one day, and it seems the only change was the battery voltage (?). If so, use a multimeter to
1. Confirm battery voltage is 12.5 or higher before cranking. Confirm voltage whilst cranking- @beginning and end of cranking.
2. Any low voltage condition whilst driving will cause all kinds of strange errors/symptoms
3. Is your battery staying charged- is the alternator doing strange things? Put a new regulator in it or find a known good replacement, perhaps take it to an auto electrician to test it properly if you don't know how, experience helps with diagnosing faulty alternators.

All guesses tho, I Am Hardly A Pro.

If the above fails, maybe the DWA is triggering the EWS. But read the codes and you'll know for sure.