Possible lack of power ? Help me inspect - Alfa Romeo Forum
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Possible lack of power ? Help me inspect

Alfa 147 1.9 JTD 16V , 140HP, year 2003.
Car is mechanically fine ,except for a stuck open thermostat and an EGR valve that the last owner has probably never cleaned, since he wasn't even aware what It was. Oil will be changed tomorrow to full synthetic.

1. Yesterday I got myself in some street racing against a Golf Mk.4 TDI , presumably 110-130BHP.
And well, at around 120km/h , I couldn't overtake him. I had my pedal to the metal, 5th gear. He wasn't accelerating faster, we were neck and neck all throughout our little race. Gearing disadvantage perhaps, but my RPM was high enough to feel it probably isn't that.

2. When driving the car, I always feel as if the first 2K RPM are sliiightly dull . There is still an obvious accel but nothing like what it happens at 3K RPM, for example. I understand turbo lag, but some overtaking powers below 2K RPM would be nice.
3. Another thing I notice weird is when I rev-match. The pedal requires a serious hit to even register the blip .

And besides that, what are usual culprits that limit the sheer speed of the vehicle? Things to look at, places to clean etc? No pre-cat or main cat, so they can't be it. No black smoke from the exhaust. I haven't done an ECU/throttle reset, because of radio, but that'll be soon fixed. New turbo hoses, no oil leaks in the engine.

As a whole, excuse my rant ,but nowhere else could I get the answers + working night shift is as boring as it gets.
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A choked EGR and running cold... won't help at all.

Your car will have the less-catastrophic plastic swirl flaps, but they can still fail to work/get covered in carbon-oil goo, and turn the car into basically a 4-inlet port head rather than 8-port. Check the actuator bar across the top of the inlet stubs is still there, attached and operating the valves, and not leaking from the pivots (losing boost). See Autolusso - Swirl Flap Delete or search the forum.

You could also check the turbo VVT actuator for full movement back to the stop at high vacuum. ELearn says 10mm total movement, but it's nearer 20mm. Sticking means carbon and/or rust inside the VVT, which will lead either to under or overboost. The vacuum hose between the actuator and the vacuum solenoid itself is inclined to develop tiny pinhole leaks, which also mess up VVT operation, and should be replaced if in any doubt at all (3mm ID silicone boost tube, cheap on eBay).

Throttle reset does nothing on the diesels, since they don't have a throttle. Diesels are basically WFO with power moderated via the fuel supply and turbo.

Your car should do 120-125 mph, not kph
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Originally Posted by halftone View Post
A choked EGR and running cold... won't help at all.

Your car will have the less-catastrophic plastic swirl flaps, but they can still fail to work/get covered in carbon-oil goo, and turn the car into basically a 4-inlet port head rather than 8-port. Check the actuator bar across the top of the inlet stubs is still there, attached and operating the valves, and not leaking from the pivots (losing boost). See Autolusso - Swirl Flap Delete or search the forum.

You could also check the turbo VVT actuator for full movement back to the stop at high vacuum. ELearn says 10mm total movement, but it's nearer 20mm. Sticking means carbon and/or rust inside the VVT, which will lead either to under or overboost. The vacuum hose between the actuator and the vacuum solenoid itself is inclined to develop tiny pinhole leaks, which also mess up VVT operation, and should be replaced if in any doubt at all (3mm ID silicone boost tube, cheap on eBay).

Throttle reset does nothing on the diesels, since they don't have a throttle. Diesels are basically WFO with power moderated via the fuel supply and turbo.

Your car should do 120-125 mph, not kph
A new thermostat is on the way, EGR I'll try myself to fix. The car wasn't in pristine shape when I got it, If I'm honest. The car does indeed reach 130MPH (210KM/h) , but that was of course on a long stretch of road. My little race was on a town's main road, where It started off at 50km/h.
Since it's my first vehicle, is there a diagram somewhere of the engine so I can navigate for which parts you're exactly talking about? I don't know where the actuator bar is, or the VVT actuator.
P.S. Found a lovely abandoned car ramp next to my place, everything looks good, besides a worn CV joint that is indeed the cause for a knock I was experiencing. Moving it around it sounds as if it's shattered. Are those expensive and do it cause any damage to drive with it until ,let's say, January 2017?
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Recently I noticed that my car started pulling harder after 2k rpm maybe at about 2100-2200, while previously it pulled at about 1800-1900. I believe this happened after my top turbo hose was changed and my uneducated guess is that it has something to do with the MAF sensor that I think is attached somewhere on it... So you could also check that. But getting the pull at 3k rpm is not normal.
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Quote:
Originally Posted by xen0s View Post
Recently I noticed that my car started pulling harder after 2k rpm maybe at about 2100-2200, while previously it pulled at about 1800-1900. I believe this happened after my top turbo hose was changed and my uneducated guess is that it has something to do with the MAF sensor that I think is attached somewhere on it... So you could also check that. But getting the pull at 3k rpm is not normal.
I changed my top turbo hose at an Alfa Romeo orientated garage, it's a the club garage in Varna (Auto Teh 1) . I doubt he messed it up. Yes, I get a pull at 2K, but the real strong one comes at 3K RPM.
I'm not sure if there is actually something wrong, I just expect it to be slightly faster. Can't say I have the option to drive another one with the same spec in my city. With the HP it's got, I'd expect it to pull much harder than something with 110ish.
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