This Volvo has no power when driving up a hill and also no power when accelerating. I can get the vehicle speed up to 60mph but it takes forever to get there.

The engine is a turbo charged model.

The plugs are good.
I am POSITIVE there are no vacuum leaks.
The exhaust system is not blocked.
In PARK the car can freely rev up to 5,000 rpm's.(haven't tried to rev it higher).
The fuel filter is new (Bosch).
No smoke coming from the exhaust.


The CEL was on, I scanned the car and came up with 3 codes. They were for:
Large EVAP Leak
Small EVAP Leak
Random Misfire.

I figured the Random Misfire was due to the small evap leak code. I have since replaced all the cracked vacuum hoses (small evap leak) and I also replaced a broken hose on top of the fuel tank (large evap leak).

I cleared the codes....the EVAP leaks are gone but the Random Misfire code still pops up. The car does misfire under load.


The car has the same problem as before I replaced all the hoses. Nothing has changed.

It's almost as if the Throttle Position Sensor is bad. But I measured it looking at both its numeric value as well as on a graph and it is working properly.



Only under load does is not have power.


There is a hi way near my houst....it travels uphill for about 8 miles....My car will only do 25 miles an hour driving up the hill.

Any ideas?

I was thinking Mass Air Flow sensor, but there was no MAF obd code.

 

Is she in limp mode?
Any up flashing transmission warning light showing on the dash.
May have a PNP switch or transmission solenoid issue?
Just a guess.

 

No, not in limp mode. However, when cold, there is a hesitation on first to second gear upshifts and yes, the upshift arrow will come on. I understand that when the upshift light comes on, it is the computer calculating different values and the upshift arrow lights up to inform you to shift up to the next gear to optimize fuel economy.

When traveling at a any steady speed on flat ground, the car runs fine. But let's say for example; I push the gas pedal to gain speed.....the car starts misfiring for the duration that the gas pedal is pressed. If I lift up on the throttle slowly, the car will stop misfiring and very slowly gain speed. It's like a balancing act between pushing the pedal down enough to keep accelerating yet don't push the pedal down so far that the engine misfires. It's like I have to hold the throttle at the threshold of misfiring to gain speed.




What/Where is the PNP............and which solenoids are you thinking? Can this solenoid be accessed without removing the transmission from the vehicle?

 

Have you checked timing? What type of plugs are you running? What car do you have?




Check to see if you have an intake manifold leak.

 

My old thread.....just thought I'd post the solution to the misfire-under-load problem. Maybe this info will help someone out.

Ok, so the problem turned out to be that the turbocharger was bad. The exhaust wasn't spinning up the turbine blades fast enough to keep up with the rate that the engine rpm's were increasing......for what ever reasons, the turbine shaft had too much linear end play.

I replaced the turbocharger with one I pulled from a local wrecking yard and the engine runs great again.

A year and a half later I replaced the head gasket......six months after the head gasket, the transmission started slipping.......had to say good-bye to the car due to the escalating costs of repairs.