Loss Of Power / New ElanScan File

[simonbuk]

So I took my car to a dyno as it still didn't seem as well as it should've been. Dyno showed 126bhp and they said it was running richer and richer as the revs got higher.
I have done a new ElanScan file from cold start up for a few minutes of driving. It suggests my temp sensor is working, it boosts up to its maximum, what else should I be looking for ? I did perform a vacuum leak test a shortwhile ago (with mountain bike trye and pump!) which appeared ok.

Can somebody cast their eye over my file and see if anything shouts out at them please ? I've been told to check compression too which I will at some stage (when I have a tester).

SJB1.zip

[chrism]

Yep EScan shows your air/fuel ratio keeps dipping down to the 'rich' values...



Could it be a dodgy/intermittant O2 connection I wonder? My m/plug behind the w/arch depinned - and there's also supply and (more importantly) earth O2 connectors that I might be inclined to check with a m/meter at the m/plug in the engine bay where you plugged your new sensor in

I've tried superimposing spark + temp data and there appears to be no connection - nor is it regular, which is why I'd (personally) suspect electrics first.

[simonbuk]

That dip down corresponds to when I open the throttle (I think) so not sure it's a connection. But worth checking still though

[KenS]

Notice that the knock count is unusually high, it shows a burst of knocks on the acceleration. Traditionally I think this is a symptom of timing being too far advanced causing pre-ignition, and this would also explain lack of power, but looking at the timing plot does sort of indicate the base timing may be correct at around 15 or 16 deg, has the base timing been checked recently (needs to be in Service mode and procedure to reset the IAC followed)?

plot2.jpg

[KenS]

Just seen your other post which confirms base timing was checked good. Another cause of knocks is bad or low octaine fuel?

[simonbuk]

I have been putting the good stuff in it since i got it and the announcement that older cars should use the E5 stuff

[simonbuk]

Anymore ideas why I seem to be getting a high knock count ? Just been out for a run, sometimes lurches a bit at low revs , doesn't always seem to pulled hard throughout the gears, some slight hestitation.

0505sjb2.zip

Got some new leads and coil packs coming just in case.......

[RonR]

Had a quick look at your file Simon,

The knocks coincide with hard acceleration / fuel consumption. Maybe low fuel pressure causing lean mixture ???
I downloaded the raw data into Excel and plotted Fuel consumption (Engine speed * Injector duty * Injector pulse width) compared with Knock counter:

Graph.jpg

[simonbuk]

Thanks for having a look Ron.

I assume there must be a fuel pressure regulator ? Or something that controls the fuel pressure in some way.

Maybe I need to buy another gadget to check the fuel pressure .

[Tuga2112]

Thanks for having a look Ron.

I assume there must be a fuel pressure regulator ? Or something that controls the fuel pressure in some way.

Maybe I need to buy another gadget to check the fuel pressure .

yes there is one. on the driver side of the engine, on the side, between the top cover and the intake plenum. if you follow the injectors you will find it easily.

id like to learn how you add somethign to test the pressure in there, i find the locaiton a complete pain to access. very interested in learning how someone can test that practically

[chrism]

Restriction in the tank or fuel line? Blocked fuel filter, perhaps?
Just a couple of thoughts...

[simonbuk]

Restriction in the tank or fuel line? Blocked fuel filter, perhaps?
Just a couple of thoughts...

Yep - all possible things .....

[FunElan]

This thread mentions measuring fuel pressure: viewtopic.php?f=38&t=24751

Sadly...there's no valve on the fuel rail like many other cars, so it's a bit of a faff.

FPR is not hard to change if the system is de-pressurized, and if you're going to be doing the filter. Just have to remove the engine lift hook.