Hi,

So I recently got this car because I had another 92 400SE before and loved it--but someone had to go crash into it.

The problem:
- the car is slow to start moving, even hitting the kickdown does nothing... it can barely compete with a snail when picking up. However, when it gets going, it can go quickly
- recently it has started messing up a bit further with all the gauges going wonky every time I attempt to accelerate from a light (albeit pushing the pedal a bit further than I would when already moving)
- from scanning the car it seems that some of the control modules are unable to communicate with each other and the car is in limp mode (except for the fact that it can go more than 50km/h)
- the check engine light is perpetually on due to the comms error
- the transmission doesn't seem to change gears, even when changing between R, P, and D... but never has an issue when in a fresh start going from P to D/R

What has been tried:
- the computers have all been replaced with ones from a working car that was scrapped, but the same problem remained... so the original computers were restored
- the transmission conductor plate was replaced, but the problem remained
- the CANBUS cables were visually inspected, but they appeared to be fine

What needs to be tried:
- replace the CANBUS wiring between the computers... there's a scrap car with all the same canbus wiring to take it from


Does anyone have any other ideas?
Thanks in advance for any help you can offer, even if it's just a wish of good luck. If anyone else has this issue, feel free to contact me or post here.

I would start by looking at the actual communication between the modules using a scope.
It is possible that one module is "bringing down" the communication between the modules and damages the packets.
Can you access a scope?

Hi ytech15

First off, thank you very much for your reply!

I don't think I have access to a scope. Do you have any links to one, or a brand and model of one?

I'm leaning away from corrupted data packets because the problem persisted despite having replaced all the computers with those from another car--but I can't say with certainty that the car didn't have the same problem.

Did you replace every single module? FYI even a faulty SAM module which have nothing to do with the drivetrain can damage the network.
A scope isn’t a cheap device.. But that’s the only way you can actually see what's going on and fix the problem..
Also, can you post a current fault code reports from all modules?