Lack of Turbo 'urge' - possibly?
 

Well, after 4 months of delays caused by numerous things, I finally managed to take my C70 for a short 'exploratory' drive:cool:

I was naturally cautious about driving the old girl for the first time - ears on high alert for suspicious noises (not helped by having a boot full of tools and other clanky stuff!).

On the whole, I was pretty relieved to discover no serious-looking problems - bar the odd rattle to be expected of an unrestored 21 year-old Volvo:regular_smile:

The auto box gear changes were virtually imperceptible, with no thumping or flaring. No misfiring or warning lights on the dash. No groaning from the steering, or juddery brakes.

So far, so good.....

However, I got the feeling that several of the 240 horses had either fled the stable - or been shot for French supermarket meat counters:confused_smile:

Possibly because I was being ultra-cautious, possibly because of the auto box, but there didn't seem enough 'urge' from a 2.3-litre turbocharged engine. The last comparable petrol turbo car I've owned was a long-departed Citroen CX GTi Turbo - with a rattly pushrod engine of 168PS - which seemed far more accelerative in nature. I had expected something similar of the C70, but couldn't really detect the same sort of 'on boost' shove.

It's early days yet, so maybe when I have full confidence in the car I can begin to drive it accordingly. Not having anything to compare it against doesn't help, either.....

Can anyone suggest a good take-off point for fitting a boost gauge to check that the turbo is actually doing something? This would purely be for temporary diagnostics - not a 'Barry Boy' accessory:teeth_smile:

The car has had new oil, spark plugs and an air filter. While fitting a new timing belt I did notice good compression when rotating the crankshaft - but I haven't done a 'proper' compression test.

Use the vacuum tree near the throttle body to attach a boost gauge to (you'll probably have to remove the plastic cover over the throttle linkage to get access)...

Thanks for that. The engine is an 'ME7', so doesn't have a throttle linkage - but hopefully the rest of the plumbing is similar.

Is the engine management ECU 'clever' enough to trip the 'check engine' warning light, if there's a large leak between turbo and inlet manifold? I couldn't hear any suspicious 'leaky' noises, but then again I couldn't really hear the turbo spool up either....

Hopefully I'll have a bit more time to investigate further - work, the weather and other commitments have really got in the way to date:mad:

I'm not familiar with the ME7 engines but I assume you'll find somewhere suitable to attach a boost gauge around the throttle body area... I have an 850 with the boost gauge in the instrument cluster, so it's a bit easier to see what's going on...

Once you've got it set up, put the auto box in sport mode (to stop it changing up too soon) and floor it, peak power is around 5000rpm I think? You should be getting around 9 psi peak boost...

Assuming it is under-boosting, there are any number of potential causes, but no harm checking all the boost pipes and vacuum lines in the meantime. A large air leak would throw a check engine light I would think...

Sorry to be the bearer of bad news - but an ME7 T5 70 (S/V/C) series is never going to give you a proper old school 'turbo shove' as the ECU map is too progressive, coupled with the electronic throttle body & an auto box will only ever deliver smooth power. Plenty of it. But smoothly.

If you want the : '..foot down. 1k RPM..wait for it 2K RPM...wait for it ...3K RPM....whoooosh...arrf.torque steer/wheel spin/massive grin.....4k RPM pulling, 5k Pulling....6K pulling,world going blurry.....dip clutch, change up..and repeat (on a private road obviously)...buy an 850 T5 manual.

However as others have mentioned, change all the vacuum lines, the boost control solenoid & the rest of a stage zero, most of which you've already done by the sounds of it, and that will ensure you have as close to 240 hp as possible!

Thanks, '101':regular_smile:

From some reading, it would also appear that boost pressure is limited to a lower value in the lower gear(s?), to give the auto box less of a wringing.

Tapping in a boost gauge will at least confirm that the turbo is at least doing something. If a smoother power delivery is the norm then I'm happy with that - I'm just wanting to reassure myself nothing is too kaput!

The ME7 cars are set up for GT driving, not boy racing, you can wring more hp with various MODs, but not as easily or cheaply as with the earlier me4.3/4.4 ECUs

So which engine is stronger I have also noticed that me7 t5 are lazy and generally feel under powered especially in a v70 due to the weight I nearly sold my v70R the week I got it because I was so disappointed with the performance I've had turbo cars before with a smaller engine but the power was so much more usable I noticed that the boost on the volvo was low about 11 psi in first and second gear