Lag

[MattM]

Noticed there is a fair bit of lag with the turbo, especially noticeable when WOT to the 5-6k rpm, change up and WOT again. After the change up there is some lag in waiting for the turbo to come on full again. Anything that can be done to improve this?

[wegal]

If your shifting up at 6000 rpm and getting turbo lag then Id say your map needs a look at. Shifting at 6k should still leave you well within the power band of the turbo in the next gear. Mine can shift up ( auto box) at 4000 rpm and still be on boost in the next gear with no lag.

What RPM do you get when shifting up ? 2500 rpm, 3000rpm ? That should be well within the rev range for your turbo to produce instant power. Take it for a drive and try and see whats happening at what revs, if your getting lag at mid range rpm then there is an issue.

These cars from factory start spooling at 1500 rpm, and are producing max torque at 1500 rpm. (I think I remember the volvo power graph for the S60 T5 right).

Id have a quick check round for boost leaks before blaming the map however. Did you get the HLM map ? If so fire it back at hamish, Im sure he will sort if for you.

[MattM]

I'll have a play with the RPM and see what it does. Does how quick you change gear make a difference or is it a case of if it's in the power band you should get instant full boost?

[graemewelch]

had std map stg 1 and 2. never had turbo lag on any stg of tune.

[wegal]

I'll have a play with the RPM and see what it does. Does how quick you change gear make a difference or is it a case of if it's in the power band you should get instant full boost?

I dontknow about that on the volvo, as mines an auto it changes pretty quick.

On my lancia it doesnt care if I shift fast or slow, its down to the engine RPM and how much exhaust gas is flowing into the turbo. However the lancia has a narrow power band, so a slow gear change may drop it out of the boost. Its a 20 year old car though so its old technology. Yours simply should not lag.

[dave stew]

I'll have a play with the RPM and see what it does. Does how quick you change gear make a difference or is it a case of if it's in the power band you should get instant full boost?

Presume yours is a manual? If so, then it's down to your two feet and a bit of co-ordination!!

[MattM]

Kept an eye on things on the drive to the gym tonight, must be in my head seems fine.

[Dan850r]

After i changed my turbo for a new one i checked the recirc valve on the old turbo as i was getting irregular boost, it was split quite bad, maybe worth a look at, bit tricky to get to but is an easy one to sort

[LeeT5]

As with anything on these cars, you gotta read the codes else your clutching at straws. The symptoms you describe are problematic of the BCS (Boost control Solenoid) and or a small vac leak. Backed up by the fact that since your first thread you have switched off and restarted the car and now you say it drives ok?
Characteristic of a sensor playing up and when the fault occured the ECU bypassed the faulty sensor and ran a 'Limp home' map to save your engine. If the BCS readings go out of tolerance then the ECU cannot rely on the information it provides, so it bypasses it. When you restarted the car some time later the BCS worked normally again so it behaved normally and the ECU was happy and the car drives normal again. The fault should remain logged and wont put on the EML.

1. Read codes.
2. Fix/replace worn or broken part
3. Report back with your findings.

[MattM]

I should think the BCS works fine, had a new one put in last month. I think I may have been seeing something that wasn't there, I'll keep an eye on it.

[LeeT5]

I should think the BCS works fine, had a new one put in last month. I think I may have been seeing something that wasn't there, I'll keep an eye on it.

Think!! Just because its new, doesn't mean its ok!! If you don't read the codes you'll never know.