Why does my 1996 Volvo 850Turbo lose power when i get the speed to 50 but when i let off of gas it picks power back up and the surging stops but every time i get my car to 50 mph it does the surging & the large loss of power. Can anyone help

 

to the forum Jermie

Moved to 850 section

 

Do you have a check engine light on ??

Have you checked all your turbo ducting from the air filter all the way to the throttle body to made sure all the clamps are properly seated and none of the rubber has any rips in it ?? The hose on the IAC too ??

 

It's not too horribly uncommon for spark plug wires to behave that way, and probably the coil could cause similar problems. The problem being that you don't have the ability to spark reliably at those conditions. The speed comes into it because the problem is much worse just as the car goes into 4th gear. It is probably possible to be sure about this without replacing anything, but we need to discuss it more.


The air inlet ducting (Kiss4afrog said "sucting" above but he meant ducting) is a good suggestion too. It's a long way from the mass air flow sensor to the engine. If any air gets in or out in that ducting you'll have trouble.

 

Partially clogged cat??