1997 v70r if i (accelerate)hard it loses power

gswede · Post by **gswede** » 18 Jun 2015, 17:46

Could be your fuel relay acting up, not uncommon. Have you tried driving with the relay pins jumped? Google jumping fuel relay, easy as cheese.

chuffin hell · Post by **chuffin hell** » 19 Jun 2015, 10:51

Well same running bad must of been coincidence
Weres fuel relay

Post by **scot850** » 19 Jun 2015, 12:51

Hi Adam,

I am fairly sure your 98 will be the same as mine with '2' fuel pumps. As the fuel tank is like a saddle there is a second pump (although Volvo call it something else and it has a pipe that runs across the front of the fuel tank to the main pump.If the 2nd pump fails, then you don't get the whole fuel tank worth of gas, but also there is a pressure regulator on the other pipe from the 2nd pump that runs over to the RH rear of the top of the fuel tank. I'll try to find a post I did giving the details of all the fuel pipes and emissions stuff on my 2000 R.This may be a little different to your car as things changed in 1999 and 2000.

https://www.matthewsvolvosite.com/forums ... =1&t=69887

Have a read at that and it may help you see more of what is at the back. Your car is AWD?

There is also a second valve that is part of the fuel rail assembly that is known to fail. It is if I recall on a 98, at the Cam-belt end of the rail and underneath it.

Neil.

chuffin hell · Post by **chuffin hell** » 22 Jun 2015, 14:02

Am getting no where
Fuel pressure is good under load
All vac pipes changed
Turbo works fine
Good vacuum

Sommerfeldt · Post by **Sommerfeldt** » 23 Jun 2015, 08:37

But have you changed the TCV?
You're overboosting or overloading the TCV w/ the chip, that'd be my guess. Since everything works, lines and hoses are changed and there's fuel, then as some others have said, there are control issues.

- S

chuffin hell · Post by **chuffin hell** » 23 Jun 2015, 15:03

Sorry yes tcv changed for a good one no difference so changed back

Sommerfeldt · Post by **Sommerfeldt** » 23 Jun 2015, 16:53

Yeah, but if you just switched one out for another like it, then the problem would likely be the same anyway... Since everything's working, your hoses are good, the car starts, runs and boosts, then you've a problem with control.

You have to take note of what Neil and abscate said - what's your boost pressure? Higher than ~14, and you likely need a different TCV all together.

- S

chuffin hell · Post by **chuffin hell** » 24 Jun 2015, 01:54

Hi yes I've lowered boost to 12 .it used to run great before problem at 18 psi
I will re check everythin again

Sommerfeldt · Post by **Sommerfeldt** » 24 Jun 2015, 02:24

Well, if everything works at 12, and you don't get the cut-out, then you've got your culprit right there.

So I'm assuming that you have an MBC, and you cranked the boost up to 18, and then the troubles set in?

- S

chuffin hell · Post by **chuffin hell** » 24 Jun 2015, 11:36

No everything not better still runs bad

1997 v70r if i (accelerate)hard it loses power

Re: 1997 v70r if i (accelerate)hard it loses power