Phil's 98 A4 AHA 2.8QM
Phil's 98 A4 AHA 2.8QM
Vehicle: 98 Audi A4 Quattro
Engine: 2.8 AHA 30v V6
MegaSquirt: 3.57SMD MS1 029y4 code
MegaTune: MegaTune 2.25p3/Tuner Studio(Trying to get in TS, but I know Megatune far better)
Ignition: Wasted spark DIS, stock coils with the internal circuitry bypassed. BIP373 coildrivers in a separate project case(super easy with the 3.57SMD's DB15 output)
Fuel: Stock injectors
Other: No TPS used for MS(Audi TPS work backwards, a no-go for MS), dedicated GM coolant and IAT sensors for MS. Idle controlled by the stock ECU(surges for some reason on startup).
Description: Quite a pain to Megasquirt. Being the first(that I am aware of) to MS one of these 2.8 A4's I had no diagrams or instructions. I had to probe every wire I thought I would need(narrowed it down by color and Phil logic). This is a piggyback setup(OEM ECU controls too much stuff to ditch it), so I had to leave the factory ECU all of it's inputs, but with the help from DIYAutotune's website I was able to do some sensor "sharing". The two big things that made this install difficult were, the injector wiring and that I had forgotten "Stim For Wheel" turned on(giving me erratic RPM until I turned it off). As far as the injector wiring goes, pretty simple huh? I thought so too. For some reason I had 12v on the positive wires when I checked then to ground, but I still got no fuel... Very perplexed. Well after about a month I checked the ground wires against ground and got 12v, I traced the wires but never did figure it out. So I cut all the injector wires and ran new ones(the Phil way). It took me a little while to get it started, but now it runs pretty strong. As much power as stock if not more, but it does Stumble slightly(no TPS). I'm sure most of you are probably wondering why I don't just install a TPS, no room. Even to pull the intake elbow you have to remove the intake manifold. I tried leaving everything as stock as possible for now, but I do have mods planned.
Eventually I would like to remove my cats, remove my mufflers(enjoy the noise). Then after I get bored with that I would like to turbocharge it, but with the lack of room under the hood it would have to be a rear mount setup. I will try to post pics soon, if any of you have any questions PM me and I'll get back to you. I would post an MSQ but I have a lot of tuning to do first.
Re: Phil's 98 A4 AHA 2.8QM
the MS2 extra code works perfect with the backward audi TPS.
I modified the MS1 code too,wich works now perfect with the stock tps.You can also change the TPS wires,if the stock ecu is disconnected.
If you like,i can send you the s19 file with the backward tps,code 29y4.
Re: Phil's 98 A4 AHA 2.8QM
Re: Phil's 98 A4 AHA 2.8QM
![Smile :)](./images/smilies/icon_smile.gif)
Re: Phil's 98 A4 AHA 2.8QM
Re: Phil's 98 A4 AHA 2.8QM
Re: Phil's 98 A4 AHA 2.8QM
Thanks,
Phil