Hesitation on Boost

[woody]

Hi all. The old girl is running sweet now that she's back on full boost!

I have noticed however a slight hesitation whilst boosting; not much, just a little judder. Since the oversize and rebuild etc, I haven't had the RICA304 map re-checked; could this be the culprit? or could it be something simpler like HT or Plugs?

Any advice would be great.

[merc85]

flywheel sensor buddy

[woody]

flywheel sensor buddy

Ahhh, dirty or broken?

[oblark]

flywheel sensor buddy

A crank position sensor is an electronic device used in an internal combustion engine to monitor the position or rotational speed of the crankshaft.

[960kg]

Hi all. The old girl is running sweet now that she's back on full boost!

I have noticed however a slight hesitation whilst boosting; not much, just a little judder. Since the oversize and rebuild etc, I haven't had the RICA304 map re-checked; could this be the culprit? or could it be something simpler like HT or Plugs?

Any advice would be great.

Any turbo engine with a misfire on full WOT boost is 99% ignition problem , either plugs or coils. Adjust the plug gap first back to the normal setting as these wear with miles.

[woody]

Any turbo engine with a misfire on full WOT boost is 99% ignition problem , either plugs or coils. Adjust the plug gap first back to the normal setting as these wear with miles.

Should I still entertain Flywheel sensor aswell?

[960kg]

Should I still entertain Flywheel sensor aswell?

I had this with my T4 and started at the beginning and i only got as far as the plugs which i replaced with new Volvo ones and it cured my problem.

It is up to you which way you go about it but if you start at the cheapest part to replace and work through to do with ignition then go to sensors.

While the plug leads are off check the long plastic part for cracks as the spark can leak and jump across the gap to earth on the block, wrap any cracks with insulating tape and try it first before replacing, also clean any ignition wire connectors for oxidisation.

Hope this helps you?

[oblark]

Should I still entertain Flywheel sensor aswell?

As I said "A crank position sensor is an electronic device used in an internal combustion engine to monitor the position or rotational speed of the crankshaft."

The sensor tells the ECU where the piston are and at what speed they are doing.

A misfire is an ignition problem eg plugs, leads, cap or rotor arm.

[960kg]

I am always willing to learn but is a hesitation at high boost not a misfire?

In all my years of cars a hesitation must equal a misfire as it is the engine not firing properly so it hesitates.

If you have a crank position sensor or a cam shaft sensor gone tits up then you would know it as well as having it`s own generic code and light up on the dash.

[dob]

I have just had this on my c70 about 3k revs on full boost.
New volvo plugs fitted today and the problem is gone.
I recomend to try new volvo plugs first cheap(ish) and simple to try.
dob

[PHIL V70R]

try the maf...mine did the same sort of thing turnd out the maf was U,S..

[The Flying Moose]

Woody If you have the car at Marham I'm uk bound on Sunday night and have many spares ins senators etc you can try. By your description I would say ignition and your more than welcome to try the new dizzy rotor arm sparks and leads in my car if you wish to confirm or rule it out.

[woody]

Sorry Mr Moose for not replying sooner. Thanks for the kind offer but I've sorted it with a new set of volvo plugs!!!!!
I'm on terminal leave now so it's goodbye Marham and all it's politics. Cheers all with your advice with this!