Jerky acceleration when engine hot, overheating?

The car is a 1993 Rover 420 GSi Turbo (petrol)

I'm trying to solve a problem of random jerkiness under hard acceleration. The jerkiness happens when the engine is warmed up/hot, and gets progressively worse.

I've checked the spark plugs, they had a black sooty ring around the base of the thread, a dead white insulator nose, and the cathode? (the bit that you gap) is vey clean. Is this due to overheating?

If the engine is overheating, what should I check? All the temp guages seem to be working OK, but it's funny that no matter how hard I drive it the dash temp guage never gets above half-way.

Thanks, Steve :)

Reply to
Stephen A
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Reply to
dave

If the temp guage doesnt show overheating why consider it? Are you losing coolant?

Sounds like a fuel problem, check the injectors are working correctly

- perhaps it just needs a damn good service!

Sorry not to be too helpful!

Dave

Reply to
Dave Rees

| If the temp guage doesnt show overheating why consider it? Are you | losing coolant?

Because of the condition of the (new) plugs.

| Sounds like a fuel problem, check the injectors are working correctly | - perhaps it just needs a damn good service!

I'm not losing coolant, and yes it may be a fueling problem as I believe the ECU cools combustion by making the fuel richer.

| Sorry not to be too helpful!

Any help is very much appreicated.

Thanks again, Steve :)

Reply to
Twinkletoes

You sound a little confused here. The condition of the plugs that you describe could be down to the plugs overheating, this is not to be confused with engine overheating which is different altogether. Plug overheating is usually caused because the plugs are the wrong value for the engine, check you have the right plugs. You don't mention whether or not you checked the plug gaps. If the gaps are set wrong then this can cause poor running.

As far as the temp. guage goes, that sounds about right. The gauge should sit about half way and not vary much at all. An erratic temp. guage usually points to a fault somewhere.

HTH

Reply to
Michael Cotton

acceleration.

Agreed with both points. Change your plugs.

I got a set of these

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4 x IK20 is the correct fitment for the Rover Turbo lumps - I've been very pleased with mine. Cured a very slight jerkiness.
Reply to
Nom

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