Misfire just a few weeks after new turbos

[bernhund]

As the title says..my 2.5's developed a misfire which is particularly noticeable when driving rather than at idle when the needle stays pretty stable at around 800revs. Two new turbos and the mapping adjusted accordingly by Jetstream a few weeks ago, I'm wondering whether the plugs could oil up for some reason? Could it be running a bit rich and do this? When I pull each lead off the coil there is clearly a change in sound suggesting the spark is at the plug.
I thought I'd just run it by you before going up to Bruntingthorpe again.

Edited by bernhund on Sunday 7th October 16:42

[Gadgeroonie]

if its happening at 800 rpm and very light throttle i suspect the throttle tps needs adjusting

the car does not know if it is idling or driving

which ecu do you have ?

[bernhund]

Hi Gadge, it seems ok at idle but as soon as the motor labours it becomes obvious. I have a late ecu that was actually replaced with a recon recently.

[sundance002]

bernhund said:

Hi Gadge, it seems ok at idle but as soon as the motor labours it becomes obvious. I have a late ecu that was actually replaced with a recon recently.

At what rpm does the misfire occur ? Is it constant at this rpm?

[Gadgeroonie]

whip the plugs out and check they are clean and gapped correctly

is it ok on full throttle

[bernhund]

Couldn't be sure right now about the revs at which it occurs, but an example would be on a motorway, cruising at around 70mph would appear fairly normal. Then hard on it to overtake and I'd hear it and feel it, though the car will still pick up well so no significant drop in power.

[Gadgeroonie]

is it possible you are overboosting - sounds like the ecu is cutting the power

[Hollowpockets]

Overboosting normally comes with a massive bang and the car lurching the times its happened to me, id start with changing the plugs and gap them correctly, i had a set i thought looked fine but were causing a misfire.

A dodgey coil sounds more likely if you are able to drive normally with power only slightly affected.

Based on several cars lately your ecu might need a check over.

[bernhund]

Sounds like I'd better work from the plugs backwards. Cheers

[Gadgeroonie]

how much boost is it making ? where did you get the ecu from ?

has it run like this since you got the newer ecu fitted ?

Edited by Gadgeroonie on Monday 8th October 10:54

[bernhund]

Gadgeroonie said:

how much boost is it making ? where did you get the ecu from ?

has it run like this since you got the newer ecu fitted ?

Edited by Gadgeroonie on Monday 8th October 10:54

It was all set up by Jetstream just a few weeks back so I figure all that is good, except of course the recon ecu could fail I suppose. I'd best give Dave a shout to see what he thinks as all has been well until now.