Low down power - 2.8

[SteveZ3]

Hi all,

New to the forum, had a quick read around and looks pretty good!

Bought my 2.8 1997 Z3 in November and I love it!

Had a few issues with rain leakage, seats moving and exhaust clamps rusting. These are all fairly common issues though so I wasn't too bothered and the repairs are all easy.

The only thing that's bugging me is the power low down in the rev range. I feel as though I really have to rev the engine to feel a real pull.
I've heard the Vanos seal can cause this issue.

Would like to hear thoughts from others. Cheers.

 

[GazHyde]

Hi Steve,

There are various things that might be causing issues, but I'm not mechanical so will leave it to those who can! If you get chance to post up an introduction of you and your car it will save this thread being dragged off topic by people waving hello at you
https://zroadster.org/forums/introduce-yourself.41/create-thread

Gary

 

[BMBabe]

The Tech guys will be along shortly with loads of advice

 

[Lee]

Starting with the basics: When was it last fully serviced? (Plugs,all filters,oil etc)

Failing that I personally had a MAF problem (the sensor after the airbox) try unpluging it and see if the car feels more responsive.

Various sensors can cause sluggish proformance so worth plugging in some tech.

Lee

 

[SteveZ3]

It was fully serviced only about 2000 miles ago, currently got 98k on the clock.

I will try the MAF sensor when I get chance - thanks for the advice.

I am also looking to change the water pump, thermostat and maybe some other components of the cooling system.

I'm also getting a bit of a squealing noise when pulling away slowly - any ideas what this could be? (Yes I'm slowly adding problems to the list sorry )

 

[Lee]

Well tonight I'm doing exactly those jobs on a 2.8

The thermostat and waterpump I will let you know how it goes.

Squeling noise, is it coming from the rear or front?

Lee

 

[SteveZ3]

What a coincidence! Look forward to your feedback Lee.

Coming from the front - sounds like a belt noise possibly?

 

[zedonist]

Squealing, It's probably the belt tensioner, worth changing these when changing the belts.

 

[Lee]

The job itself was very easy. The viscus van has to be removed. The work cannot be done with it in place. I even tried removing everything around the fan but still found it had to come out. So with my huge 32mm spanner on the fan shaft (left hand thread push clockwise) I removed the larger belt and got a rubber grip round the water pump pulley to hold it in place becuase it rotates as you push down.

Photo's show old plastic impeller vs new metal impeller.

Another for idea on location.

Hope this helps.

Lee

 

[SteveZ3]

Very helpful mate cheers. Looks fairly straightforward!

 

[Ashbandicoot]

The job itself was very easy. The viscus van has to be removed. The work cannot be done with it in place. I even tried removing everything around the fan but still found it had to come out. So with my huge 32mm spanner on the fan shaft (left hand thread push clockwise) I removed the larger belt and got a rubber grip round the water pump pulley to hold it in place becuase it rotates as you push down.

Photo's show old plastic impeller vs new metal impeller.

View attachment 12058

Another for idea on location.

View attachment 12059

Hope this helps.

Lee

What brand pump have you used Lee?

cheers

Ash

 

[Lee]

I will need to dig the box out the bin, GSF stock two types of water pumps. One has a plastic impeller and second has a metal impeller which they call the premium part. £45 on the site but with my trade account its £28. Stick with the metal impeller as this is the weak point in the 2.8 engines.

Lee

 

[Ashbandicoot]

I will need to dig the box out the bin, GSF stock two types of water pumps. One has a plastic impeller and second has a metal impeller which they call the premium part. £45 on the site but with my trade account its £28. Stick with the metal impeller as this is the weak point in the 2.8 engines.

Lee

Okay, I have a 'trade' account with ECP Did you replace the belt and pulleys whilst you were there?

Ash

 

[Lee]

Likewise, ECP are very hit and miss in my neck of the woods double check the parts before leaving. I replaced both belts (ones aircon) the pulleys dont need replacing. Its also good to change both tensioners but mine were fine so I regreased the bearings and left them be.

Lee

 

[t-tony]

Ditto re check the parts before leaving. Only last Saturday morning to my cost, they got it wrong again. Did I actually say ...again?

Tony.

 

[SteveZ3]

Changed the water pump today, along with drive belt.
I was going to change the thermostat, but it turns out that eurocarparts are really bad at actually getting you the right part.
They gave me the wrong thermostat - something I should have checked before getting the car in bits.

Hardest part about the job was probably getting the water pump out of its position as it was very tightly held in even with nuts removed.

I'm a bit annoyed because I've flushed the coolant out but now have to do it again when I change the thermostat! I think it's on its way out as well as sometimes the engine will get up to temperature and then the water temp guage just randomly starts dropping a bit and then goes back up.

 

[DivideBYZero]

I get better low down pull after changing to a K&N panel filter, but only measured with my super accurate Butt-Dyno...