C70: Turbo spiking

[Yosser]

Originally Posted by Guardsman1

How much would that cost Yosser? Just frustrated now as im piling money into it but not finding the solution.

No cost dafty!

I'm just an amateur who has built up a few bits and a little experience along the way.

I'm in Edinburgh, pm me if you want to drop by.

[Guardsman1]

Ive sent you a PM mate let me know when your free, cheers

[Jp003]

Hi

So the parts you got off other members on here were they second hand or new?

Also we never confirmed the correct preload was setup on the actuator fitted.

I asked for the Bosch MAF number to double check you have the right one on the car. Swapping for the one that was on the car doesn't mean you 100% got the right part!

If you don't want to spend money start on the basic checks that cost nothing and work from there.

If you have fitted second hand parts how do you know they work correctly?

I know exactly how you feel as I've thrown hundreds at my car to get it right and some parts were not needed. Everything I've done has improved the car and should give me 14 years more use out of the car. That's down to you and if you want to keep the car long term. I'm past the point of ever getting my money back so it's more for long term keeps. Better the devil you know.

Get the car hooked up and see what VIDA says

You can perform a lot more tests using the software and test ETM and pedal etc correctly.

You will get there just stick at it bud.

[Guardsman1]

The actuator is from mitsibushi. Both of them and the MAF(which made no difference) is Bosch 0280 218 088 then underneath 86 70 115. Smoke test tomorrow then heading out to see Yosser so hopefully something is noticeable.
Im having the actuator checked again on Saturday and inter cooler.

[Jp003]

I'm not 100% without looking but don't think that's the right MAF m8 for your car!

What's your engine number?

[Jp003]

Originally Posted by Guardsman1

The actuator is from mitsibushi. Both of them and the MAF(which made no difference) is Bosch 0280 218 088 then underneath 86 70 115. Smoke test tomorrow then heading out to see Yosser so hopefully something is noticeable.
Im having the actuator checked again on Saturday and inter cooler.

Okay if this is your car then your MAF is correct. VOLVO / C70 I 2.4 T5 Cabrio / C70 I Cabrio / 2.4 / 147 kW / 08/2002 - 03/2006 / B5244T7

If your spiking and the turbo wastegate actuator has been setup correctly then maybe your compressor bypass valve is torn or weak. This will leak boost pressure back into the intake and is supposed to protect the turbo from boost spikes?

Interested to know what is said about the actuator tomorrow. Think the preload on that will be 1.8PSi if your running a low pressure turbo. 4.4psi for high pressure turbo.

[Yosser]

I've spent a little time looking at the car this afternoon but I'm not sure I made any progress.

Initially I read it with Vida and there were a few unrelated and probably historic cabrio roof related codes but the ones of interest were:

ECM-3503 Misfire, at least one cylinder - No match
ECM-3533 Misfire cylinder 3 - No match
ECM-3543 Misfire cylinder 4 - No match

I cleared the codes to see what would come back - nothing did (apart from a brake pedal sensor fault ECM-9400).

I'm not sure what the 'no match' means.

Apart from a bit of a visual inspection and poke around I changed the plugs, the bcs, and tested the actuator with a hand pump. The actuator is not stuck in any way and appears to start opening at around 4psi.

I tried it with another MAF and it seemed the same.

The car drove quite well but did feel to have a certain uneven patch, it was really hard to pin down as it was quite subtle.

Even after a few test runs no further codes were logged.

I'm not sure where to go next, I was hoping for something a bit more obvious!

[960kg]

Are you sure that error code is brake sensor?......it depends which model Volvo.... i thought it was Knock Sensor which would explain the drop in boost because of detonation etc.
If it is Brake Sensor adjustment i have read that it will effect boost ,but i don`t know why?

[Yosser]

Brake sensor is what Vida said, I never looked into the fault as it didn't seem relevant to the problem. It was a persistent fault though, wouldn't clear.

[Guardsman1]

Brake sensor is the only fault that all other computers have flagged over the last couple of months and not disappeared after reset. Im thinking maybe just maybe the computer has been trying to tell me something and ive just dismissed it because they dont seem to relate. Sorry forgot to take down vehicle number. It is a MK 1 2.4T 197 bhp January 2003 convertible.