[urq] She runs ! No more cut-out!

Louis-Alain Richard laraa at sympatico.ca
Tue Mar 7 20:54:33 EST 2006

Yes Eric, you read well: your car is now a runner, no more cut-out at any

The audience : (applause)

Me: Thank you very much.

Now, before taking her for a well deserved ride, I have to do some more
little work. Like finding the problem with the non-functioning brake lights.
Somebody has tapped into the brake circuit for god knows what reason. She
should be ready for this week-end.

What was the problem, you ask ?

Well, I could say that it was the plumbing. In fact, the previous mechanic
has plugged the top nipple (on the wastegate) to the intake manifold. This
way, the wastegate was seeing boost pressure on both side of the diaphragm.
No a good way to have it control the boost...

But this was possible because the warm-up regulator (WUR) is not vacuum
controlled anymore, it's a WUR from another car. So there was a free port on
the intake manifold "vacuum tree". But this confirms that nobody tried to
rectify the plumbing before changing parts. 

And the idle switch was not triggered when the throttle was at rest; so this
may explain why someone messed with the mixture in the first place, and
replaced the WUR. Oh well.

And the air temp sensor connections were less than optimal; the resistance
of the sensor is in the 20-30 ohms range; the ECU was seeing 110-120 ohms at
the connector/ecu interface.

And the pressure hose going to the ECU was brittle.

And the gasket between the air filter housing and the fuel metering head was
not properly placed. Another small air leak.

Now, with my stock ECU in it, she is not very fast. And without the proper
WUR, she doesn't start real quick. But all the parameters of the ECU are OK;
duty-cycle, temp sensor, WOT and idle switches, reference and TDC sensors.
And the engine dies _right_now_ when I open the oil cap. So the engine is
air tight.

Now more questions to the list:

- In my circa-1985 Bosch K-Jetronic booklet, they states that some WUR have
an enrichment function at part throttle. That's why they are pressure
dependent. So, must I reinstall a correct WUR on his car or Eric will hole a
piston ? 

- Martin, you states that each MAC02 are not created equals. If we find
another yellow-tagged chipped ECU for his car (we found one in the
marketplace ads last week), what are the pins that we must displace ?

- if the timing belt was 1 tooth from the correct configuration, what would
be the effect on the engine ? Is this enough to completely change the power
and behavior of the engine ? Is it really noticeable ? I am wondering since
I am never sure if the timing belt is exactly where it should be.

Thanks in advance,


More information about the urq mailing list