[urq] I am puzzled...

[Louis-Alain Richard]

Today I took a test drive in Eric's car. But before going, I reinstalled
the correct blue tagged ECU, (Martin scared me about that pinout
change...). After that, the car would not idle, backfires were heard in
the intake, there was no way I could drive the car like that. Back to my
own stock yellow-tagged ECU, and everything was fine.

What puzzles me is the fact that someone before me made the car kinda
drivable with this junk ECU. Even if the car was cutting out at
3000-4000 rpm, it would idle and start at the twist of the key. So it is
possible to overcome a dead MAC02 with just screwing up the mixture...
Good data point to remember when you are stuck in the middle of nowhere
with a dead ECU...

Now, during the road test with my ECU, after a fast bit of highway, when
I coasted to a red light the engine kept pulling... Clutch in, RPM is
now 6250, and the engine is hitting the rev limiter... Oh oh...

When I stopped the car on a deserted secondary road, I open the hood
just to see that the air temp sensor had come loose, and one of its
bolts is stuck between the intake manifold and the throttle lever...
Damn, I know I torqued the bolts correctly, not too much to prevent
breaking the tabs of the $$$ sensor, but I guess I should put some
Loctite on them now... Scary moment.


Being naturally positive, here is what I learned today:
- the rev limiter is of the "abrupt" variety, cycling each second or so,
a contrario to the newer engines where the limiter is "softer".
- the engine doesn't cut at any RPM :-)
- there is some security in the fact that the urQuattro brakes are
hydraulically assisted. I was able to control the engine with just the
brakes to quit the highway. 
- never leave without a 10 mm wrench in your pocket.
- having a crowded engine bay is a good way of keeping the parts in the
said engine bay...

Cheers !

Louis-Alain