Pinking

[bigjohnh]

Hi everyone,

After getting my car back complete with new (second hand) fuel pump, temperature sensor and ECU and a brand new pattern Lambda sensor the engine now 'pinks' under load below about 2200 rpm. The fuel economy is a little better maybe 5 or 10% but that could be down to proper fuel atomisation now that the pressure is restored.

I would like to avoid melting a piston if at all possible so need to fix this soon.

Any suggestions

Is it possible to retard the timing or richen the mixture or is this all controlled by the dreaded computers?

I might try the old brain back in just to see if that's the prob.

Over to you

John

This post has been edited by bigjohnh on July 23, 2007 12:53 pm

[Assich]

What fule injection and ignition system are you running with. If it's got a distributor and no tdc sensor then maybe it needs timing adjusted.

[bigjohnh]

Yes the fuel injection is Bosch motronic 3.2 with a seperate distributor, I will consult the Haynes Book of Lies this evening. I thought the car took care of all that so further research required.

Thanks

John

[Assich]

My 1991 2.0i had a distributor on it with no tdc sensor, throttle pot etc. Basic drive by cable rather than drive by wire and thus the distributor set the timing.

[bigjohnh]

Spoke to a local engine tuning place and suddenly enlightenment dawns:

The new (2nd hand) ecu I put in to see if that was the problem came from a Mk2, with the later engine. My engine is the Mk1. I will swap the ecu cback and see if that is the problem, which I hope it is.

I think that referring to various history files that the 2.0 TCT engine was revised at some point to give a bit more power, hence the different timing.

John

[bigjohnh]

Cured,

I performed brain surgery today and replaced the old ECU. The result is complete restoration of smooth engine and no pinking.

In conclusion the older engines have slightly different timing to the later ones, the wrong ecu will run the engine but not without pre ignition. So you can use a newer ecu for fault finding but not recommended for long term use.

John