V70R 03model, poor running.

[Nev]

Afternoon,

Car running slowly... Not too slow but doesn't pick up as it should, feels like its about 100 horses down.
Under hard acceleration it seems to hold back and I can feel it surging. It used to go like stink so something is wrong.

No fault codes showing, no warning lights.
I found a vacuum leak this afternoon, fixed.
Checked plugs and they look perfect, correct colour, gap etc.
Checked air filter, it's got a cone filter that its always had in my ownership. Found that for some reason there was a rubber restrictor taking diameter down to 65mm. Seems odd to me that one, so removed just in case the hot weather meant it wasn't breathing properly.
Took out for a run and it was a touch better, but still pants. Yes, it is 27 degrees out here, but it is surging as opposed to just slow.

I have the car running LPG or petrol and it does the same on both which, to me, means its not fuel related.

Any ideas welcome...
Cheers, nev

[graemewelch]

saying as theres no codes it could be possible the cat is blocked. ive sold a few downpipes duevto this problem.

what was used to read the codes. only volvo software will pick up all codes. if a generic one has been used there could be codes there but it cant read them

[Chad]

Hi,

does it do it all the time?

any specific temperature?

The cats blocked would cause that too.

[Nev]

Just a generic code reader, so yeah, probably won't pick up everything, if anything useful.
Yes it does it all the time. Not really noticeable at part throttle unless you know it's doing it. Just feels like its holding back, but at full beans its like its being strangled.

I've not really noticed a slow depreciation in performance which is what I would expect with blocked cat.

I thought it may have been the waste gate stuck but not really sure how to check. The actuator rod moves, although I was very surprised at how strong the spring is. I haven't had chance to fit a boost gauge to see if its actually boosting.
This wouldn't give the surging tho, just low performance.

[M-R-P]

Could be fpr, blocked cat, blocked fuel filter, split intercooler... Can't think of anything else offhand. Luckily, being a 03 plate, you won't have to worry about the throttle module.

[Harvey]

Just try the cars reader , key on lights on dash,hold read button on L/H stalk on then press rear fog light switch 3 times very quickly then the display will show if there are any faults set in the car.
Let got of read button when it says reading codes or something like that.
Press the read button to move down the list.
Best have a pen and paper as there are a lot of things it can say.

[Nev]

I don't think it's the fpr or filter as it is the same on petrol or LPG.
Would a split intercooler cause the surging, never had a burst one before. I can't hear anything as if its blowing excess air out, but the car is so noisy I don't know if I would.

[Nev]

Just try the cars reader , key on lights on dash,hold read button on L/H stalk on then press rear fog light switch 3 times very quickly then the display will show if there are any faults set in the car.
Let got of read button when it says reading codes or something like that.
Press the read button to move down the list.
Best have a pen and paper as there are a lot of things it can say.

I shall give that a go. Didn't know it was possible.
If the wife doesn't get back too late I shall try later.

Thanks for all the help up to now.

[silverhorse]

If the wife doesn't get back too late I shall try later.

Thats your problem right there. Your wife is driving the car!

[graemewelch]

if there anything i can help with give me a shout im just up the road. cant do much in my condition though

[Nev]

Well, checked codes. A couple are ok.

Srs, dim, rti,swm, phm, all say Ready so seem fine.
Everything else says checking or dtc set.

I haven't had chance to look up what things are yet as I am doing 12 hr shifts at mo, but I guess that dtc set means probs have been around for a while and Checking suggests there are new issues developing.

Sum, psm, sas, tcm, all say checking.

Oh joy, now to trawl through the possibilities.

Hopefully I will have a bit of time tomorrow to check intercooler etc.


Thanks Graeme, one day I will come and see you. Hope you are ok

[Harvey]

The only ones that say dtc set need a look at

Turn key to position II or start the engine.
Press and hold down [READ] on the turn signal lever, and press the rear fog light
button 3 times quickly.
Press [READ] to advance to the next item.

Text Window
Description

CHECKING DTCS
Checking the Diagnostics Trouble Codes.
DTCS IN VEHICLE
Diagnostics Trouble Codes present in vehicle.

DTCS IN VEHICLE
BCM DTC SET
Brake Control Module.

DTCS IN VEHICLE
SAS CHECKING
Steering Wheel Angle Sensor.

DTCS IN VEHICLE
SRS CHECKING
Safety Restraint System

DTCS IN VEHICLE
ECM DTC SET
Engine Control Module

DTCS IN VEHICLE
AUM READY
Audio Module

DTCS IN VEHICLE
CEM DTC SET
Center Control Module

DTCS IN VEHICLE
DIM READY
Driver Information Module

DTCS IN VEHICLE
DDM DTC SET
Driver Door Module

DTCS IN VEHICLE
CCM CHECKING
Climate Control Module

DTCS IN VEHICLE
PDM DTC SET
Passenger Door Module

DTCS IN VEHICLE
PSM CHECKING
Front Seat Module

DTCS IN VEHICLE
REM CHECKING
Rear Electric Module

DTCS IN VEHICLE
SWM READY
Steering Wheel Module

DTCS IN VEHICLE
UEM READY
Upper Electronic Module

[Nev]

Well, looking at the codes it's got to be to do with the ECM, as the rest seem to be to do with ancillary things like doors.

However, there are a couple that mean nothing to me so may be causing issues.

UEM
REM
CCM

Cheers

[Nev]

Forgot to say, I read the meanings for the code just don't know what the REM is for etc

[Nev]

Well, codes read with dice.
Nothing too bad, not as many as expected. Mainly stupid things like door locks and mirrors.

The one that concerns me was ECM-6806 flow too low

Will be connecting a gauge in the next couple of days to see if its even boosting.
I rechecked vacuum pipes and intercooler again and found nothing wrong.

Which leaves me with it being TCV, MAF, or blocked cat that restricts flow to give same symptoms, as has already been suggested.

Graeme, your cat replacement pipes, are they a straight swap for the front pipe?, and how much do you charge?

[graemewelch]

your welcome to try my maf and tcv if easily removed. youll have to do the donkey work though as im not very mobile at minute. as for down pipe yes they are a straight swap. for a 200 cell down pipe your looking at 275 ish

[Nev]

Thanks Graeme.

I'm going to check boost before anything else. It feels to me like the waste gate is stuck open. Had that issue on a saab years ago. Sort of hoping its mechanical thing rather than electrics.

When you say 200 cell, is that still a cat but free flowing?
I would actually like to remove cat altogether and just have a straight pipe if the car will run like that.

[graemewelch]

yes thats a 200 cell cat. standard cats are 400 cell. i can to a decat or a pipe wear you can use a 200cell cat or straight pipe. can have a bit crack about it some time

[jdavis]

REM is rear electronics module. Controls rear lights, wiper, fuel flap etc

[Nev]

Update.

Boost gauge fitted, piped from back of actuator so should be reading ok, although can change fairly easily to one of the other pipes from TCV.

My boost gauge doesn't sit at -0.3bar when off the car, but assuming that where it sits is 0 then my max boost is 3 psi. If where it sits is normal then it reaches 0 on the gauge. I have another gauge in a different car that always sits below zero too, same make so I think gauges are poor. Tim gauges.

Tried car last night with MAF disconnected and it ran with less surging, but still no power.
Connected gauge and tried with MAF disconnected then connected, no difference.

So it looks like I have no boost, hence no performance.

Not MAF related.
Is there anything else other than TCV that controls boost. I haven't had chance to get pipes off and physically check waste gate inside turbo. Engine is very hot and it looks a bit tight in there, so that will have to wait.

Just an aside, I ran the engine without the MAF pipe on, if I had a pipe to the outside of the car I reckon it would Hoover up little dogs and children and the induction noise was noticeably louder.