PLEASE HELP!!! Engine boggs, screeches and dies after transmission replacement!!

[thor6069]

Hello all,

I posted a few weeks ago about some automatic trans problems. I decided to replace the automatic with another. After reading ALOT in this forum (thanks) and getting parts I finally got the trans in and everything back together last night. Well, I got the car started but it immediately started making a loud screeching noise and the car boggs down in surges then dies. It will start but then idles erratically up and down, almost at a constant rate then dies after a few cycles. I would attribute it to an electrical connection if it wasn't for the loud screeching. A few notes about the reinstall:

- I had went ahead and cleaned the icv while the intake was off
- I accidentally rotated the engine the wrong way while removing flywheel bolts... can this damage anything?
- While working on a car I had to hook the battery back up to move the windows.. well the next day I forgot about it and moved the starter (trans was already removed) and got a HUGE spark.


So my question is.. could any of these things have been the cause of the sudden change? The car engine ran fine previously. I really hope I didn't damage anything major, but the car sounds terrible and I am hesitant to start it back up again..... does any one have any suggestions? I was thinking that maybe when I shorted the starter I fried the alternator and maybe that is why it is screeching and bogging.. but I really don't have a clue and don't want to start the car and risk damaging something major before I have and idea of where to start... Please let me know what you think. Much thanks!

[mt_goat]

Did you replace the torque converter? I probably would have put a new one on while it was off. I doubt those 2 things you mentioned are causing the problem.

[aht bmp]

What part of the car is screeching? Belts, tranny, what? Any SES lites on? What codes present?

[thor6069]

I didn't replace the torque converter.. but maybe I should have. I don't have a code reader and I shut the engine off pretty quickly. I didn't seen any lights on though. The sound almost sounded like it was coming from near the alternator which is why I guess that could be it. I don't believe and alt exerts enough force to bog the engine down though...? I could try starting it again but afraid of consequences. I wanted to check and see if anyone had any ideas first, or if someone else has experienced this. Thanks for responses.

[aht bmp]

A couple of thoughts ... it begins with the noise. You're going to have to know what's making the noise before anything else. A stethoscope and a friend will be your best friend. It may hold the answer or no answer at all. If the problem isn't related to the noise here's a few things to look for.

I don't think it likely that anything fried the alternator, although it's possible that a blown fuse, such as the fuse in the e-box (there are 5 30-amp fuses there) control everything from o2 sensors to the main dme to the transmission and everything in between. Also, another common problem is a poor body ground after a big job like the transmission. Make sure that the body ground from the engine has a clean paint-free surface. Also, make sure that all the sensors are plugged in ... like the MAF sensor at the air box, etc.

I would determine the noise, then check fuses (including in the e-box). A BMW code reader might be a must before it's all done. Communicating to the modules to see if any electronics are not working or if any communication between modules is pretty crucial.

Stumble and poor idle can also be a result of poor battery voltage (remember the computers feed from the battery not the alternator and if the battery has a bad cell a good alternator won't fix it) or even a natural relearn process if the battery's been disconnected for a long time.

[choffa]

Did the trans slide relatively easily to the bellhousing, or did you have to pull it in with the bolts (struggling). Possible that the torque converter drive lugs were not aligned with the trans pump drive lugs. Converter should rotate then drop into the bellhousing as you install it. If the lugs are not aligned when the trans is bolted up, it will destroy the pump.

[thor6069]

I appreciate the responses guys. I will attempt to start it again and see if I can diagnose the noise. I'll check and recheck wiring. Unfortunately I'll be out of town for 3 weeks for work, so no working on it for a while. ( I was trying to get it on the road by this friday... but no luck) I will be sure to check everything you have mentioned.

As far as the torque converter... I took extra special car to make sure the drive lugs were aligned. (I read about a few horror stories) The trans bolted up pretty easy to the bell housing, there was actually some space in between the fly wheel and torque converter, so I doubt that is the issue.

I appreciate the responses and I'll keep you guys updated.

[thor6069]

Well I had a chance to start it up and listen and it sounds like it is coming from the ICV. Maybe I messed something up cleaning it up,or possibly assembled it incorrectly. I'll have to take it apart when I get a chance.

[thor6069]

Hello all,

So I pulled the ICV today and I had a question. Should the door inside open all the way? I looks like it is only partially open (maybe 20%) I tried to pry it open with a screwdriver, but no luck. ( I didn't press too hard) It will open and close, but just that 20%. Is this normal? It seems to me that is should open all the way.....? Thanks!

[walker7182006]

is it a obd1 vehical?

[thor6069]

yeah is is obd1.

Update: Well after taking it apart (twice), knocking the icv a couple times and rechecking electrical connections... now it is working... I can't explain it, but the issue is resolved. Maybe something was loose but either way it is fixed. Thanks all... on to the next issue!