Side effects of M-TDI conversion on A4 ALH chassis

[Holeshot]

Has anyone done this?

I'm growing very tired of all the electronic funkyness (yes, that is a word...) that composes the ALH.  Hard starts, failure to add fuel when I REALLY want it to, etc.

I haven't done any experimentation yet to see if the A/C compressor and other such things like the speedometer, radiator fans, etc. will still operate if the engine isn't running but the key is on...but I'd like to keep my losses to a minimal when it comes to the comfort and automatically operating items in the car.

For the cost of an M-TDI pump, I'd eliminate SO many variables that all work against me when it comes to making power with the ALH and keeping it reliable.  I know I'd for sure loose my cruise control, but I rarely use it anyhow...

Heck, a good "chip tuning" would put me in the range of price of an M-TDI pump...!

Thanks for any insight,

Matt

[jtanguay]

i would stick with electronics if i were you.  i would only consider an m-TDI on my MK2 jetta which would need the wiring harness from a mk3 tdi to run.

don't forget you'll need to install the cable pedal...  and i dont think the spedometer will work, or even the rev counter??  worth it??  i think it would be about the same either way you look at it.

now, what i would recommend:  hook up resistors to the sensors to give the computer a false reading.  basically linear feedback.  the computer won't compensate much if any at all.  it will be about as good as putting an m-TDI pump on.

[RabbitGTDguy]

Also, as far as the MKIV chassis/production car in the states here is considered...you have some major emissions issues, etc. to contend with the DMV, especially alternating the fueling system, ECM, etc. I don't believe it would be able to pass inspection...

As always...don't quote me on it. The electronics on the TDI are not all that complex, and can/should be contended with properly and its probably the best setup for it legally and performance wise.


Joe

[Holeshot]

I'd like to eliminate the MAF - I think mine is flaky and I don't want this to be a yearly $90 'normal maintenance' item.  I'd also like to run a BIG turbo that does not have VNT.

Eliminating the MAF and allowing for a traditionally wastegated turbo can be done with chip tuning, but I remember someone telling me that the ECM in my '98 NB is non-standard and not able to be chipped.  To top it all off, I can't swap a newer ECM into my car...nice.

Can you elaborate on hooking up resistors to the sensors?  This very idea was discussed in another thread where someone made ~180hp and 240ft-lbs to the wheels with just resistors...no bigger injector nozzles or pump heads needed.

An M-TDI only needs one wire just to run - the shutdown solenoid.  The ECM should take care of the rest, but it might like to know that the engine is running to give the alternator the field signal to keep things running at ~13.8VDC.  Goodie - big hurdle there, eh?  Maybe, maybe not.

Throttle cable - no biggie.  Speedometer - they're overrated. haha - no, I'd like to have one of those.  My '94 Ram lost the speedo/odo/cruise control when I converted from the automatic to an NV5600 6-speed and more importantly...NP241DLD to the new style NP241DHD that lacks a boss on the tailshaft for hall effect sensor for speedo...it's a bit of a pain to not have a speedo.

As for emissions/DMV/legality - none of that is an issue out here.  We have no emissions or safety checks.  Yet somehow, the air isn't polluted and there isn't a problem with substandard vehicles causing accidents.....go figure.  Leave this task up to the people without intervention by the goverment and it just gets done - what a concept!

I grew up in MA (and lived there most of my life...) and vowed to get the h-e double hockey sticks out of that hole filled with laws and BS red tape.  I do miss my family/friends out there and definitely miss the seafood.

Beers,

Matt

[jtanguay]

I'd like to eliminate the MAF - I think mine is flaky and I don't want this to be a yearly $90 'normal maintenance' item.  I'd also like to run a BIG turbo that does not have VNT.

Eliminating the MAF and allowing for a traditionally wastegated turbo can be done with chip tuning, but I remember someone telling me that the ECM in my '98 NB is non-standard and not able to be chipped.  To top it all off, I can't swap a newer ECM into my car...nice.

Can you elaborate on hooking up resistors to the sensors?  This very idea was discussed in another thread where someone made ~180hp and 240ft-lbs to the wheels with just resistors...no bigger injector nozzles or pump heads needed.

An M-TDI only needs one wire just to run - the shutdown solenoid.  The ECM should take care of the rest, but it might like to know that the engine is running to give the alternator the field signal to keep things running at ~13.8VDC.  Goodie - big hurdle there, eh?  Maybe, maybe not.

Throttle cable - no biggie.  Speedometer - they're overrated. haha - no, I'd like to have one of those.  My '94 Ram lost the speedo/odo/cruise control when I converted from the automatic to an NV5600 6-speed and more importantly...NP241DLD to the new style NP241DHD that lacks a boss on the tailshaft for hall effect sensor for speedo...it's a bit of a pain to not have a speedo.

As for emissions/DMV/legality - none of that is an issue out here.  We have no emissions or safety checks.  Yet somehow, the air isn't polluted and there isn't a problem with substandard vehicles causing accidents.....go figure.  Leave this task up to the people without intervention by the goverment and it just gets done - what a concept!

I grew up in MA (and lived there most of my life...) and vowed to get the h-e double hockey sticks out of that hole filled with laws and BS red tape.  I do miss my family/friends out there and definitely miss the seafood.

Beers,

Matt

well the sensors use resistance to calculate a value.  so all you really need to do is find out how much resistance a sensor has for optimal performance, and swap in a resistor on the harness hookup for that sensor.  you can pretty much eliminate the MAF too, but i think that the car would lag considerably.

[Slave2School]

MAf delete is possible with a chip. Most chips tunes only cot about 350-400, not the near 1500 a new rebuilt M pump would cast, plus all the other things you would need.

[RabbitGTDguy]

Lucky you with emissions and not having any issues.

I've talked the diesel swap from gas around here with many people as well as altering the stock configuation of a 95+ motor and we have issues.

Guess then again too...depends on "what" inspection shop you'd go too. Friends in "high" places are nice to have.

On the m-pump. They can be had for alot less and built for alot less than 1500.00. There is also a ton of tunability that you can build into the pump and gradually make use of those eliminates as you go with simple adjustments. For those of us that don't have chip tuners handy, nor the money to spend, or knowledge in rewriting programing, etc. its an awesome option...especially on the older platform swaps.

If I had all the wiring, ECM, etc. etc. for the next TDI i'm working on to be swapped into my b3, I'd go eTDI...but its just not in the cards as I don't have these items and paying 250+ for a harness alone, another 200 for an ECM, then all sensors, maf, DBW pedal, etc. It adds up to over what I'd have into building and/or having help building another mpump. Having been inside the pumps before and knowing those with knowledge that they are willing to share, help and contribute to the project...makes it quite a bit less expensive with the most "on the fly" tunability...once again, knowing where you want to go with it.

In either situation...there are options

chip tuning does cost money and adjustments need to be made for modifications that you do. You need a firm planting on "where" you want to go with the motor and "what" you intend to do. Otherwise, reflash, chip, etc. gets pretty costly....even with the ability to run multiple programs, etc. and there is still circuitry and potential failure involved.
Thats not me arguing against it...but the mpump is truly a 1 time deal, install and the tuning is all up to you. Each has its own costs, merits and degrees of tunability but in the end...its your decision.

To each his own...there isn't a clear cut picture here as to what is better, worse or the lot.

There is someone I know up in the NE area that had talked about this as well...i wonder what his emissions restrictions, etc. would say about it...MKIV body TDI as well!


Joe

[Slave2School]

Average "Joe" isn't going to get a pump for less than $1500 is my point.  Not that it can't be done for less

By average I mean someone like me that would phone Giles up for a built M-TDI pump.  I'm sure other folks are able to do it for less, possibly even with a full rebuild thrown in there too.  Money to be made in that segment I am sure.

[RabbitGTDguy]

Ha Ha...

There are many more builders out there too I can think of 3 off the top of my head that have awesome reps, do a nice job and even suite to application for far less than 1500
Giles does a nice job, have heard great things and even has the bosch shop to work with as well...though, the secrets of the VE, tuning it for the best for the mTDI, etc. have been uncovered and are there for others to use and those home builders building a few pumps as well to make a few bucks. Its not what they do for a living...but its a passion, they enjoy it and will help fellow DIY'ers out.

As I already said... each has its own costs...both significant if you look at the extreme end, (I.E.  having no electronics like I don't for my next TDI build *and the last for that matter* and the cost of getting them vs. have no mechanical pumps to work with, knowledge of internal works,etc. and having to have someone else do the work). In the end...close to the same cost with a few trade off driving wise, etc.

Again...comes down to "To Each His Own"


Joe

[Slave2School]

I am looking forward to screwdriver tuning with the BMW trust me  Electronic is nice, but it isn't as handy for most folks even if the chip tuning prices are great.  However I would not consider changing a car that came intended for an electronic setup over to mechanical, (unless it is gas to diesel of course)

Back on topic:  I think you will hate yourself if you attempt to go mechanical.  If you run some sort of crazy mechanical pump setup you will need the ecu for such things as ABS, traction control, glow plugs, blah blah....I'd contemplate the purple koolaid before I undertook that mess

[RabbitGTDguy]

Electronic is nice, but it isn't as handy for most folks even if the chip tuning prices are great.  However I would not consider changing a car that came intended for an electronic setup over to mechanical, (unless it is gas to diesel of course)

That, I'm totally in agreement with


Tuning issues with the Bosch equipment isn't a huge problem and is part of the regular maintenence of a car. We just had to have the MAF done on my wifes 02 1.8T...under warranty luckily. However, the electronics in the system aren't terribly hard to work with even though "cracking" the ECM isn't as easy as some models out there on the market. I'd def. keep the electronics in this case...for all the reasons already mentioned, not to mention the issues you would run into (as mentioned) regarding ABS, glow plug control, IMB, etc. etc. There are ways around it... but thats a serious undertaking.

Have you tried to diagnose "why" you have having these problems? VAG throwing anything at you? The MAF shouldn't have to be replaced that often, many do it one time and thats it.
You aren't perhaps using an oiled filter *i.e. K&N, etc.* are you? That'll take a MAF out , among other things to look at.

By the way slave2school...not to wander off of topic again, but BMW, Mmmm ...whats your project? Sounds interesting! I'd love to have a TD beamer, would love to see what your working on.


Joe

[Slave2School]

Here is my thread, more pics on the last page.

http://vwdiesel.net/phpBB/viewtopic.php?t=10107&start=0

[Holeshot]

Wow - this thread sparked some interest...sounds like lots of folks have been down this road before.

Well - rebuilt M-TDI pumps can be had for ~$600 - so that's only slightly more than a good chip tune.  If someday I decide I don't like the chip tune...I can't exactly sell it very easily.  Or, if I want another chip tune - I get to pay again.  See where I'm going with this?

I understand electronics theory, so adding resistors is fine - but I also know that the ECM expects a range of values.  Like if I want to delete my EGR/ASV with a DG racepipe - but the ECM is expecting airflow across the MAF to drop when the EGR is flowing (mine is already turned all the way down via VAG-COM...at least it was...my car has a habit of slowly ignoring what I've stored for settings...).  Sure there's the 'Epsilonian' device, but there's more effort involved just to fool the ECM into thinking everything is OK.

As was mentioned, Giles sounds like he really knows his stuff, but he's not the only person that can build a good VE pump.

By the way, my car has no ABS, nor traction control...and I partially blame my hard starts on the ECM having ADHD and not glowing the plugs when they need to - here's why:  On several occasions, I've disconnected the coolant temp sensor and it fires off with such a roar after what seems like 1/8th of the normal crank time.  Of course, the ECM thinks it is -100°F below zero or something rediculous like that with the circuit open...so the injection quantity must be very high.  It isn't good to start the engine up like that when it isn't needed.

I still haven't had a chance to check it with VAG-COM - but I plan on doing that in the near future.  I'm just really fed up with how sensitive these ECMs are to engine modifications.  You can put injector nozzles big enough to take a shower with in a Cummins ISB or ISBe and the idle, driving characteristics and cold/hot start behavior is smooth as silk.  Not these dang TDIs - install larger injectors and you have to alter the injection quanity via VAG-COM and/or do the 'hammer mod'...no amount of messing around with these two things EVER got rid of the stumble with my old '98 NB TDI - so you can see why I'm reluctant to even try it with my current '98 NB TDI.

Beers,

Matt

[vwmike]

It isn't that your ECU can't be chipped, it's that it isn't OBD flashable. The chips must be desoldered and the ECU should be socketed. If you want to run bigger nozzles then it is definitely possible to get rid of the slow down shudder with tuning.

[Slave2School]

Wow I never knew the beetles were that stripped down, I thought all MK IV's had 4 wheel disks/ABS at least.  My 99.5 That I sold did (the 1986 BMW does too!).

I guess 1500 for a pump is a bit high depending on who you go to for your work.  Same for the chip though, once a customer of the company I was through small upgrades were free/ 50-100 depending on turbo change etc, not too bad if you ask me.