R52 Cooper acceleration issue.

[DevonLad]

Just bought an R52 which I'm happy with apart from an issue of stuttery acceleration which appears to be worse when it's cold. Happens more on partial throttle.

Can anyone offer me any advice on where to start looking??

[TimmyMallett]

DevonLad said:

Just bought an R52 which I'm happy with apart from an issue of stuttery acceleration which appears to be worse when it's cold. Happens more on partial throttle.

Can anyone offer me any advice on where to start looking??

High pressure fuel pump. If no error codes. If warmed up then it can dissappear.

[Elliot2000]

TimmyMallett said:

High pressure fuel pump. If no error codes. If warmed up then it can dissappear.

R52 will be the old tritec engine, not the PSA one, so no high pressure pump.

It’s probably coil pack on top of the rocker cover, ht leads or the plug connections to it corroded

[DevonLad]

So I have replaced the coil pack, plug leads, spark plugs, pcv valve, air filter, fuel filter and removed and cleaned the MAP sensor. This has all gone some way to curing the problem but not quite. What's my next move?? I'm thinking maybe coolant temp sensor.

[Elliot2000]

Did u check the pins on the connector to the coil pack for corrosion?
Also remove the plug connections to the ecu and look for coolant or oil contamination

[DevonLad]

Contacts looked clean but I did spray them with contact cleaner, will look into the ecu connection sometime this week. Thanks

[waftycranker]

I get jerkyness (real word?) when pulling away cold in first my R53. It’s essentially the same engine as yours.

Thought it was something to worry about but I’ve read elsewhere on the information superhighway that it’s a fairly common problem.

I’ve changed the leads, plugs and clutch but it still prevails. I just live with it as a quirk of the car now.

[TimmyMallett]

waftycranker said:

I get jerkyness (real word?) when pulling away cold in first my R53. It’s essentially the same engine as yours.

Thought it was something to worry about but I’ve read elsewhere on the information superhighway that it’s a fairly common problem.

I’ve changed the leads, plugs and clutch but it still prevails. I just live with it as a quirk of the car now.

This pretty much. I live with it on my R56. I've had it a year and it's been into 4 garages who never find any faults nor replicate it/thinks it's normal.