M3AN E36 M3 PLOG (Project Log)

[duvey 245]

Whilst I don't want to count my bridges until they're hatched and am driving around whilst touching wood...

I seem to have inadvertently solved my hesitation/miss concerns... I think.

It didn't happen all the time but the symptoms were annoying and frustrating. Idle would occasionally bounce around and I had more and more hesitation under mild load.

* I got a smoke test and replaced 4 vacuum lines - problem got worse.

* I removed and cleaned the ICV - no change.

* I swapped my carbon airbox back to stock - no change.

Then, last weekend I removed the TPS and tested it - readings were fine. I then reinstalled the TPS and re-tested and got different readings from one set of pins but these matched a known good M3 so great.

Since putting the TPS back in I've not had a single idle or throttle problem! The car runs like new...

As I say I'm hesitant to claim victory yet but the last week has been promising.

If that is the cause then I can only conclude that either the contacts were fouled or the TPS is on the way out (and benefited from a shake).

I'll keep an eye on it but at the moment I'm pretty chuffed.

Great to hear. Congrats.

[M3AN 4016]

I posted some of this in the "What did you do..." thread but I'll keep it here for the record books too.

Leaking Power Steering

This is a very, very common problem for the e36's and it occurs because the hoses degrade internally and eventually loosen at the fittings. Mine turned from an occasional drip into a constant drip so I needed to do something about it. I was fortunate to find my problem was at the bottom of the reservoir and not at the crimped ends of the hoses (although they'll eventually give way as well).

To fix this I replaced the Oetiker clamps under the reservoir with worm-drive clamps. The Oetiker clamps are are pain to remove unless you know how and I used a hook pick to lift the "tail" off the "latch" which immediately opens the clamp. Replaced those with screw tight worm-drives and not a mil spilled in the last few days.

I'll eventually need to replace the hoses but would be keen to do that only when I need/want to replace the rack.

Cold Air Intake Reinstalled

I recently removed my carbon airbox to see if that was the cause of my hesitation problems (it wasn't, that was the throttle position sensor) and have since reinstalled it. When I put it back in I included a temp probe inside it and a separate one in the engine bay - I wanted to establish whether it really was a "cold" air intake.

It does appear as if it offers sufficient isolation from the surrounding heat to do the job. Perhaps one day I'll do a back-to-back comparison with the stock box and heat shield but for the time being I'm happy. Once I'm up and running at ~50 kph temps in the intake drop rapidly to a little above ambient and at 80 kph+ the intake temp is almost ambient (it's worth noting that I'm using the stock sensor to measure ambient and I have not idea how accurate or precise that is).

So at the moment I have no codes, no leaks and it's running like a beast! Still on the hunt for the best brake options but my priority now is getting a baseline dyno (to compare to my last one in 2004!).

[Jpclarke89 20]

Leaking Power Steering

This is a very, very common problem for the e36's and it occurs because the hoses degrade internally and eventually loosen at the fittings. Mine turned from an occasional drip into a constant drip so I needed to do something about it. I was fortunate to find my problem was at the bottom of the reservoir and not at the crimped ends of the hoses (although they'll eventually give way as well).

Have just discovered this thread and had a good read through the whole thing, interesting read will definitely keep following your progress. My e36 also has a power steering leak which has gotten worse suddenly over the last week also. I'm beginning to discover all these "common issues" one by one, as this is my first time owning a BMW. So I enjoy reading threads like these that have a lot of details on even the smallest of jobs so cheers for that! Hopefully mine is the same issue and is an easy fix, will chuck it up on the hoist tomorrow.

[M3AN 4016]

Have just discovered this thread and had a good read through the whole thing, interesting read will definitely keep following your progress. My e36 also has a power steering leak which has gotten worse suddenly over the last week also. I'm beginning to discover all these "common issues" one by one, as this is my first time owning a BMW. So I enjoy reading threads like these that have a lot of details on even the smallest of jobs so cheers for that! Hopefully mine is the same issue and is an easy fix, will chuck it up on the hoist tomorrow.

Cheers and no problem. Something will help someone sometime if it's written down.

I'm jealous that you have access to a hoist! I'd spend so much more time on my car if I did!

Good luck with your power steering, keep us posted.

[KwS 2425]

Ill need to have a nosy at the bottom of my res at some point too, i have the slow occasional drip coming from my system.

I hate those oetiker clamps with a vengeance. Thanks for mentioning how to release them.... theres one on my radiator hose that ill need to release before i can put the rad back in. Was going to try cutting the damn clamp off!

[M3AN 4016]

Yeah, I sort of stumbled on the pick idea myself due to lack of space and available access to the reservoir clamps.

If you have easy access then you may just be able to grab the 'tail' with needle nose pliers and yank it off the latch/hook. That would be faster.

[KwS 2425]

I tried that but its small and was really tight. Might try side cutters to lift the tail.

Did you drain the res and remove the hoses to fit the clamps, or just put the clamps around the hoses in place?

[M3AN 4016]

Yeah, I was surprised at how tight the tail sits! It took a few goes with the pick (I was working blind though).

I didn't drain, the hoses easily stayed in place, even with some deliberately applied tension.

[Ahmedsinc 414]

Ahh, Oetiker clamps. Bane of my friggin life! Best solution I've found yet is a pair of these

Simultaneously cuts one side of the crimp and forces the b*stard things to open. Minimal effort too.

Ironic, however, that Knipex supply the crimping tool as well as the best tool to destroy them with. Guess that's the way to corner both ends of the market!

[M3_Power 636]

I have the actual Oetiker clamp tool ... if you ever need to borrow just shout : )

[M3AN 4016]

Thanks for the offer, I might need to take you up on it if I ever do all of my hoses with the Roose kit.

Clearance for a proper tool is my main concern, some of those buggers are pretty difficult to get at!

[M3_Power 636]

That's definitely true if there's bugger all room ... but the official tool has a side jaw which your standard flat pliers don't have..

[Jpclarke89 20]

Cheers and no problem. Something will help someone sometime if it's written down.

I'm jealous that you have access to a hoist! I'd spend so much more time on my car if I did!

Good luck with your power steering, keep us posted.

Yeah we have a hoist at work and a whole heap of tools etc which is really handy!

Had a look at the power steering and I'm pretty sure it was the exact same issue as yours. I replaced the two oetiker clamps at the base of the reservoir with worm drive clamps as there was definitely a leak there, although it was hard to distinguish which hose so I just replaced them both. You guys aren't wrong they are a real PITA but I just grabbed hold of them with a pair of sidecutters and twisted them until they unclamped. It's hard to see what you're doing so I just went mongrel on them haha.

There was a lot of power steering fluid running down both hoses so it was very hard to see whether the crimped end was leaking also (one end already had a worm drive clamp in place so the previous owner has obviously also had this issue before and tried the same fix), but I gave the whole area a good clean and am pretty sure it was only leaking from the top.

Those oetiker clamps are absolutely useless, I could turn both hoses reasonably easily with the clamps in place.

Will check tomorrow for any leaks but I'm pretty sure it's fixed. If there's still a leak I'll go all out and replace both hoses with all new fittings

[hybrid 1043]

A potential reason for your TPS issue will be because of resistance buildup on the connection. EG bad connection. The way the MSS50.1 & TPS works is it every time you put the car to position 2 on the ignition after the DME has been switched off for around 30 seconds. It will re-adapt the program for the TPS back to 0%.

It is known as an adaptive potentiometer. It is used to reset mechanical position 0 in relation to 0% every time the car starts. Also check your return springs and mechanical position of your throttle body plates that they are in-fact sealing 100% at idle.

[yng_750 247]

Does that mean if you turn the ignition on with throtlle open it screws the system?

[hybrid 1043]

Dunno .. haven't tried that one! ... However in my findings a long the way BMW generally cover things like this with idiot proof mechanism built into the programming.

 if ( TPS_RAW == 0 || RPM_RAW == 0 || START_RAW != 1 )  
          {
            START_CONDITION = 1;
            PRG_START();
          }

else if ( TPS_RAW != 0 && RPM_RAW == 0 && START_RAW == 0 )
          {
            START_CONDITION = 0;
            PRG_CRANK_NO_IGNITION();
          }

dunno, how i'd write it anyways.

I always wondered thought if you hold full throttle on and go to pos2 it will open up some other programming on the DME. Might give it a crack next time I remember.

[yng_750 247]

Initiate self destruct function?

[M3AN 4016]

I'll try it tomorrow and let you know!

[M3AN 4016]

^ so holding the throttle down, by any amount and into any key position (1, 2 or 3), seems to do nothing at all. At least not in my tests.

The digital rev metre on the climate control also doesn't register anything different.

[hybrid 1043]

Good to know...

Some vehicles (non BMW) have use it to allow testing of starter circuits. EG floor the throttle turn key to pos2, rest, then crank the car and it wont fire. Or in aftermarket ECUs it was used to switch motorsport functions like launch control or antilag on or off.

[KwS 2425]

Mazda rotaries use it to engage the anti-flood thing (cranks engine without injecting fuel).

[M3AN 4016]

I've just received some new parts from the US - not enough to complete my brakes or suspension but getting there.

New Rear Shock Mount Reinforcements (15 min job):

Solid Brass Caliper Bushings - these are really smooth compared to the rubber bushings but have no dust covers so will be high(er) maintenance.

And a new windshield cowl - this is an OEM BMW part but I'm missing two holes!! ?

Edited May 12, 2018 by M3AN

[KwS 2425]

you got a LHD cowl

[M3AN 4016]

you got a LHD cowl

OMG - how obvious, and stupid, is that!

Look's like I'll be doing some drilling and plugging lol!

<goes to look up part number he actually ordered!>

[sweetm3 180]

Happy New Dave

I lube mine 4 time a year, no biggy