Pinking at high speed.

[montegogt]

Latest quirk in driving my recently aquired '87 350i is that it pinks at speeds over 70mph. There is no sign of it at all at lowers speeds, even when accelerating in a high gear. Any suggestions before I pay the nice TVR wallet draining man to sort it? Oh yes it pops a bit on over run, but so did my old S.2.

Lee

[danny hoffman]

Too hot, wrong petrol, wrong plugs, wrong timing, faulty distributor?

[bluewedge]

Do what I do - drive with your fans running constantly even from start-up. Cured my persistant pinking, kept the temp at a contstant and very healthy 80c and added more smiles on my many journeys.

[david beer]

A lower cut in for the fan is easy, an adjustable one as well.

[montegogt]

My "know it all" mate, Nigel popped in to have a gloat of Friday to see what I had been doing and, immediately said that I should have a connector or the top of the fuel injection unit. He rumaged in the loom, pulled out a wire with missing connector attached. Said it was for cold starting...but it's not pinking either, though it still feels a bit rough at speed. Nigel also rambled on about changing the settings in the air metering unit and fuel pressures... Anyway, it's going to have a proper TVR 48K service, so at least it should be set up as it should be, rather than have the likes of Nigel having fiddled!
Watch this space!

Lee

[danny hoffman]

It is not that uncommon to disconnet the cold start injector. It should only run for a few seconds when the engine is very cold anyway.

Danny

[montegogt]

Well, my one is on... I will see what reports I get when it has its 48K service...

Lee

[danny hoffman]

Mine is on also - it wan't doing anything when I first got the car due to a faulty thermotime switch.

Danny

[Mark Adams]

For years I have routinely disconnected cold start injectors! They only operate under the following conditions:

1) engine cranking
2) has been cranking for less than 12 seconds
3) coolant temperature under 30 degrees centigrade

In the time that they operate they can fill a jam jar with petrol, and contribute very little to starting if the temperature is above -20 degrees centigrade.

There is some more information on pinking in the thread "Dreaming of 8 degrees".

[montegogt]

Well, it's had it's 48,000 service, and it's not pinking now...but...it's hunting instead! Anyway Mr TVR mender man is taking a look at computer thingies and air boxes... Watch this space.

[montegogt]

Problem pretty much solved. Mr TVR mender man has played with the electronic stuff, changed a vac pipe and it's running well now.
I think the problem has been caused by fiddlers over a period of time.

Lee