My e30 318is s52 swap thread

[tjcm3]

You may want to do a leak-down and/or compression test if you haven't already. Considering the amount of troubleshooting you've already done it may be time to verify that the motor is mechanically sound.

[BigD]

Adaptation is a big deal. It can be the difference between a car that runs well and a car that doesn't. The ECU runs its "stock" mixture all the time (provided the MAF is working, and it has backup tables if the MAF fails) but it uses the O2 sensor feedback to fine tune the mix all the time, also.

The purpose of adaptation is to let the motor learn around issues that come up like vacuum leaks, fuel pressure or injector problems, and the programming of the chip not exactly matching the performance of the motor. So, it does the learning at part throttle and idle (when the target is ALWAYS 14.5-14.7) then it applies the adaptation globally (because WOT fueling will be effected by vac leaks or fuel system issues also).

In his case, the adaptation is not pulling fuel out... it's just not adding it back in. But I don't think that's the real issue. M50 motors will idle happily up to 17:1, they just fall on their faces under load if they stay that lean. I think there is some mechanical issue with the motor, fuel system, electronics.... not sure exactly.

I appreciate you taking the time to write that out, thanks dude!

[windsor318is]

matt thanks for your expertice, im going to steal my moms 92 ECU switch chips, and give it a try just for the hell of it. once the mechanic installs the exhaust, im going to do my feared compression check.

bigD, i bought the motor from a RMP customer, they removed it and also did a comp test before i bought it, they also confirmed it was a strong motor before it was pulled out for a swap to a s52 that the customer had purchased at a great price with a blower already installed on it.im confident that its nothing mechanical like Matt suggested, but you never no,

so i take it i should swap o2s just to be sure??? can i try the m42 unit or modify the plug end on the factory s52 o2?? id prefer not to buy a new s50 o2 and have it make no difference.

Matt, if i were to swap chips without disconnecting the battery would the ECU not adapt to the new chip properly?just a weird thought.

[MIKe30]

Matt, if i were to swap chips without disconnecting the battery would the ECU not adapt to the new chip properly?just a weird thought.

I know you asked matt, but i have to chime in because I do this at work all the time (with fire alarm equip and know i shouldn't). Don't plug things in or take them out without killing all power to them first!!


Perhaps it has no effect on car ecu's but it made me :nice: because i find myself doing it sometimes (but on equip that i dont care if it blows up :mrgreen:). As a general rule of thumb, you kill power to electronics before working on them.

Hope you get things sorted though, i'll be keeping an eye on this thread to see what happens! good luck bud.

[BigD]

Don't plug things in or take them out without killing all power to them first!!

:stupid:

[windsor318is]

I know you asked matt, but i have to chime in because I do this at work all the time (with fire alarm equip and know i shouldn't). Don't plug things in or take them out without killing all power to them first!!


Perhaps it has no effect on car ecu's but it made me :nice: because i find myself doing it sometimes (but on equip that i dont care if it blows up :mrgreen:). As a general rule of thumb, you kill power to electronics before working on them.

Hope you get things sorted though, i'll be keeping an eye on this thread to see what happens! good luck bud.

i no i no, but after disconnecting and connecting chip 14 times, im not sure if i did it the last time with his chip.but tecnically it is disconnected when i unplug the computer harness.

[Charlie]

So, you ever get a video of this "flexing" intake manifold?

-Charlie

[windsor318is]

nope, and i was told the flexing i do have is normal apparently...

anyone know if there is any adjustment on the booster, i have to pull up on the pedal to put the pin in to lock it. so my brakes are applying once the motor is warmed up, anyone else have a problem like this. i might even have to pull it out and cut the pin on the master cyclinder side.i dunno.

[BigD]

When you thread the fork onto the booster pushrod, that's when you're "adjusting" it. You're supposed to keep playing with it until it's neutral, not tight (ie applying pressure to the booster).

[matt]

matt thanks for your expertice, im going to steal my moms 92 ECU switch chips, and give it a try just for the hell of it. once the mechanic installs the exhaust, im going to do my feared compression check.

bigD, i bought the motor from a RMP customer, they removed it and also did a comp test before i bought it, they also confirmed it was a strong motor before it was pulled out for a swap to a s52 that the customer had purchased at a great price with a blower already installed on it.im confident that its nothing mechanical like Matt suggested, but you never no,

so i take it i should swap o2s just to be sure??? can i try the m42 unit or modify the plug end on the factory s52 o2?? id prefer not to buy a new s50 o2 and have it make no difference.

Matt, if i were to swap chips without disconnecting the battery would the ECU not adapt to the new chip properly?just a weird thought.

A '92 chip won't work... a '92 ECU won't work... don't even try!

Adaptation values are stored in the ECU as long as power is connected, but I would NOT try to swap chips without disconnecting the ECU to save the values... Assuming your O2 sensor is working properly, it will adapt again very quickly.

NO flexing of the intake manifold is normal!!! We use these up to 30 psi and see NO flexing. I really think that could be part of your problem.

As for the O2 sensor thing, you can find cheap ones on ebay, just search "4 wire oxygen sensor" and look for the generic ones. The guy I usually buy from doesn't have any listed right now though.

[windsor318is]

matt i was going to put your chip in the 92 ECU and give it a whirl, not stock setup, is that a waste of my time as well?

you telling me as long as its a generic bosch 4 wire o2 it will work? my m42 sensor was only a year old, people told me i HAD to have the s50 one, im swapping it tomorrow, worth a shot, i might invest the 100 bucks for another manifold, i can always through it on my 328 if it makes no differece, no money wasted.

matt my mechanic tells me he cant pull codes off my diagnostic port its hooked up wrong....but it has power and ground, is that possible, i didnt fuck around with that part of the harness when i installed it....what do you suspect the stealer will say if i brought them a s52 powered e30?

[Charlie]

nope, and i was told the flexing i do have is normal apparently...

Who told you that? I've *never* seen an M50 (or M52 for that matter) manifold do that.

-Charlie

[matt]

a 92 DME is in no way compatible with your chip or your motor.

If your diagnostic port doesn't work, you may have a bad wiring harness. As long as your M42 had a 0-1V 4-wire O2 sensor, it should work OK. Make sure you have it connected right. You may need a bentley or the ETM to make sure all the correct wires from the harness go to the correct wires on the sensor.

[BigD]

a 92 DME is in no way compatible with your chip or your motor.

How come you can't use a 92 DME, aren't they all pretty much the same, for all M50s?

[mattdk318i]

vanos