Is the check engine light on? if so get the codes read and we can go from there. If it is not on try unplugging the MAF sensor. It is on the air intake hose toward the firewall near the air filter box. Once unplugged it will set the check engine light, but if the car runs better, you have a bad MAF. Do a search about the MAF on this forum for more info

 

 

Sounds like the MAF may be (or at least part) of the problem. Once the new one arrives put it in and we can go from there.

 

did you check the hoses from the turbo to the intercooler and onto the throttle body?

 

 

Was it running fine before you changed the timing belt? If so, are you ABSOLUTELY sure it is not off by one tooth? When is the last time the car had a full tune up? If it has been awhile I would put in new plugs, plug wires, air and fuel filter, Distributor cap and rotor and possibly a new coil. All that should run about $120 or so and will give you a solid foundation to work with.

 

 

Sounds like it could be either a weak coil or a weak fuel pump....or clogged air or fuel filter.

 

 

98 models come with a single coil that can be replaced......

 

 

Ok, sounds like a fuel or air flow issue........may have asked earlier, but do you get any check engine lights? Only other wild *** guess I could think of is a partially clogged catalytic converter or exhaust.....

 

 

We had almost the exact same issue with our S70 a year or so ago. I ended up changing the plugs, plug wires, coil, cap, and rotor and it finally went away. Sounds like you have also changed just about everything, but have you changed the plug wires?

 

 

The 98's are cheap and simple, so whatever the problem, it wouldn't be difficult to fix if you just knew what it was. If it misfires, then you don't have a clear indication of a lot of things via onboard diagnostics, unfortunately. It would be nice to know if it's going lean at high load, indicating a fuel delivery problem, or rich at high boost, indicating that your air is leaking out of the plumbing downstream of the turbo.

I hope you figure it out.

I also drive a 98 T5M. If you do give up on it, I am sure somebody else will take up the battle and have fun with it. I wish you were closer, I'd take it over.

 

BTW, I have a set of orange injectors (stock) if you want to try swapping out for the whites. IM me if interested

 

Alright folks she up and running! Changed the O2 sensors and misfire disappeared. Buuutttt i have a bad acceleration sensor so that should be the final issue!

 

acceleration sensor? are you referring to the MAP sensor?