4L5 engine map, poor combustion at full load

[zidmie]

Hi,
I finally managed to go on the road with my Cerbera, equipped with a laptop for the diagnostic.
I just burnt the lambdas, so the car runs perfectly, at idle, and low load. I can see a correct adaptative value, correct lambda values (varying between 0 and 1 quite fastly). Idle could be lower, the throttle remains at 18°, but it's ok. After the various problems I had when I came back with the car from England, I'm happy to have solved 90% of them and to have a nice car to drive!

But... (There's always a but in such messages )

When I push the pedal to 3/4, engine runs smoothly, with a lot of power.
And when I push the pedal to the end, combustion seems poor, and the power decreases a little bit. There is a different noise, as if not all cylinders were burning.

I looked at the lambda values then, it was varying, maybe more near 1 than 0 so a bit more rich, but not sure... And I looked ignition advance, the values at mid-load go up to 55°!! and at full load, I didn't have time to check but it seemed to be close to 40°, still a very high value!

Any idea is welcome!

[pmessling]

coil pack HT leads?

[zidmie]

They seem quite new, but I'll have a better look.

[pmessling]

When i brought mine under hard acceleration in any gear if started to miss, okay normal driving. i changed the HT leads, coils and plug and sorted it, although can not say which one it was, although the plugs that come out looked fine.

[FUBAR]

My money is on the coil packs

[edhorne]

Hi there

The lambdas stop adjusting the fuelling (closed loop to open loop) at 3500rpm so as the others suggest the coil packs and HT leads might be a good place to start.

Blocked air filter?

Cheers

Ed

[zidmie]

I just received the air filter, I'll change that.
I'm looking for coils and leads, thanks for the help! I'll let you know.

[zidmie]

Hello,
I finally solved my problem.
The ECU went on the security map after mid-load, I'm not sure of the reason but I think it is because my pressure sensor was disconnected (the sensor in the intake manifold).
I'm not sure of the reason, because I changed quite many things at once :
- air filter
- HT leads and coils
- one spark plug was not connected
- and I reconnected the pressure sensor.

Engine is running well now.

Thanks to all for the help!