boost lag and fuel economy question

[Rikki Kitto]

Get a new one a second hand one is as old as yours

[hunker7]

Can't decide between getting a second hand one or silicone one.

If weather allows I will boost test tomorrow and check how it runs without lambda connected.

[newsh]

Ok well you need to get that MAF hose sorted, no pressure there but there's some vacuum for sure.

Boost leak test is always first thing to do.

[hunker7]

Is it possible you have a leak in the small vac hose to the FPR? If so it will run rich on idle and lean on boost.

Have you done a full boost leak test since the rebuild?

Checked that couple if times yes? Got a new clip and it's tight. I can't remember of I did tbh, I know that MAF hose where it goes onto turbo isn't in a great shape, it's all duck taped up.

[newsh]

Is it possible you have a leak in the small vac hose to the FPR? If so it will run rich on idle and lean on boost.

Have you done a full boost leak test since the rebuild?

[hunker7]

Dunno, try it

I think if you disconnect it the ECU will use a fixed value for lambda, maybe it will run better than with a broken lambda giving the wrong value? I'm really not sure.

I shall try it tomorrow, if it improves/doesn't change much then it must be lambda. I could see if local garage can check fuel pressure

[newsh]

Dunno, try it

I think if you disconnect it the ECU will use a fixed value for lambda, maybe it will run better than with a broken lambda giving the wrong value? I'm really not sure.

[hunker7]

Thanks John.

FPR is unlikely, so is fuel pump (VDO). What would I expect to happen if I unplug lambda and it's not doing its job?

[newsh]

Fuel pump
Fuel Filter
Fuel Pressure reg
Lambda sensor
Leak in MAF hose, DV or PCV system meaning unmetered air is being drawn in between MAF and Turbo.

The ECU should correct for a lean condition if the Lambda is good, up to the point that it can't correct enough and then it should throw a code. So I would try changing the Lambda

[hunker7]

Looking at the plugs, it seems like car is running lean. So my question is, what sensors/things can cause lean running?

[hunker7]

Did you mean to say "will be"?

[macspring]

I know Automark isn't far, but he would be expensive probably?

If Mark can sort your problem permanently, his invoice will be 'cheap', tbh.

[hunker7]

Spinks is over in Scarborough about 40 miles away good man who knows these cars well

Thanks, I'll drop him a PM and see what he says

[Rikki Kitto]

Spinks is over in Scarborough about 40 miles away good man who knows these cars well

[hunker7]

Checked timing again following John's instructions and timing is right as far as I know. There are no errors either.

Open for suggestions on what else to check, and somewhere I could take her to get her running again near Leeds, but don't mind travelling for a good specialist. I know Automark isn't far, but he would be expensive probably?