Jump to content

Sluggish Acceleration....Causes?


1970Matt

Recommended Posts

  • less WHY; more WOT
  • Site Developer
  • Member For: 16y 9m 23d
  • Gender: Male
  • Location: Melbourne

Depends on what, if anything, is wrong with the solenoid. It can fail "open" which just sends all of the reference to the wastegate. It can also fail "closed" which means you'll keep boosting until the wastegate can't physically hold itself open against the turbo pressure... or anything in between those extremes. The point of the solenoid elimination is to see if you get any different symptoms other than slowest-possible-ramp to full-boost.

Link to comment
Share on other sites

  • New Member
  • Member For: 3y 2m

Thanks Mate. I will give it a go tomorrow. Is there a possibility that an Xcal3 might not pick up all fault codes? what I mean is that, are there diagnostic tools that are more sensitive than others and therefore pick up more faults.? Im thinking that maybe a sensor isnt working correctly and in turn limiting RPM.

Link to comment
Share on other sites

  • New Member
  • Member For: 3y 2m

I did check all those things and they seem ok. Fuel pressure is Good, fuel filter and injectors were recently cleaned aswell. The car was running fine for two months before this happened. Never had any fuel issues or anything...

Link to comment
Share on other sites

  • New Member
  • Member For: 3y 2m

Alright, I did connect the hose from the turbo to the wastegate and got the same result....Lazy acceleration. After returning from the drive I got the following codes again P2110 and P2105 again. But these are linked to the TPS I believe, which I changed out. So I'm confused again lol

Link to comment
Share on other sites

  • less WHY; more WOT
  • Site Developer
  • Member For: 16y 9m 23d
  • Gender: Male
  • Location: Melbourne

well, that's a good result, as you didn't get a different outcome, so I'd say your boost control solenoid is dead/dying. Clean it up and the wastegate diaphagm with lubrication and re-connect it as it was and try again. If it still goes slow it's either the wastegate opening too fast no matter what you do (e.g. a weak spring holding the 'gate closed) or the solenoid is toast and you can fix that buy just replacing it.

Link to comment
Share on other sites

  • Trust me bro...tbh ;) 8===}
  • Gold Donating Members
  • Member For: 10y 4d
  • Gender: Male
  • Location: South Australia

With an 18psi gate spring it's gonna haul ass on gate. It won't be 500rwkw but it won't be slow by any means. Even a 12psi spring on gate will make 300ish.

 

I've seen a wg flap inner arm bent to fark before, and wouldn't seal whatsover due to being sideways in the hole.

  • Like 1
Link to comment
Share on other sites

  • New Member
  • Member For: 3y 2m

Yes I agree. I guess there is the possibility that the flapper arm has been bent but what could cause that?

I also thought that maybe the flap itself has come off or something but I will need to check.

The confusing thing is that the car feels like its struggling to rev fast. If the turbo wasnt boosting then It should feel similar to N/A but I would say that it feels even slower than that. It revs evenly and I didnt feel any stumbling or something that would indicate Coils or Plugs. It just feels sluggish. When I Floor it, it feels like its taking to long to gain revs.

 

3 hours ago, k31th said:

well, that's a good result, as you didn't get a different outcome, so I'd say your boost control solenoid is dead/dying. Clean it up and the wastegate diaphagm with lubrication and re-connect it as it was and try again. If it still goes slow it's either the wastegate opening too fast no matter what you do (e.g. a weak spring holding the 'gate closed) or the solenoid is toast and you can fix that buy just replacing it.

Yeah there's the possibility it could be the solenoid but even then I thought I would feel at minimum 18 psi of power as the wastegate spring is 18 psi. It definitely doesn't feel like its has anywhere near that power. Regarding the wastegate, I did put air pressure through the hose that goes to the wastegate and was able to watch it move correctly. I tried pulling the flapper arm and it was way too hard to move so the wastegate must be putting some decent pressure on it.

Link to comment
Share on other sites

  • Trust me bro...tbh ;) 8===}
  • Gold Donating Members
  • Member For: 10y 4d
  • Gender: Male
  • Location: South Australia

I don't actually think the flapper arm is bent in your case, I was just saying I've seen it before, and this can cause no boost despite having an otherwise intact wg.

 

There are a myriad of guesses to be had here and I don't think it'll help you.

 

I mentioned earlier that a tuner can diagnose without hurting it and I covered the reasoning in my earlier post. I think there is a good chance you'll hurt it due to your lack of understanding. You might not hurt it but I don't recommend you keep flooring it to see if it fixes itself.

 

Fwiw 500 on 98 is bad enough, it can hurt itself very easily at this point, not worth the risk imo.

 

Not having a go at you, just calling it how I see it.

 

Anyhow that's about all I've got to add here, go see a tuner/mechanic and get it sorted.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
  • Create New...
'