Intermittent misfires 98 T5

brunocerous · Post by **brunocerous** » 24 Jan 2025, 09:10

My T5 has been showing misfire codes (cylinders 2 and 4) but only on my way home from the train station, not on the way there. On the return drive, the car shudders and the CEL will start to blink. If I pull over and put it in neutral, it usually works itself out.

The temperatures have been in the single digits for much of the past couple of weeks, and I'm also seeing an occasional P0172 code. Could condensation be an issue? Crankshaft position sensor or MAF? It has relatively new (under 5k miles) OE plugs, wires and Bosch cap/rotor.

Post by **scot850** » 24 Jan 2025, 11:20

Condensation freezing in the intercooler could be the issue. It starves the engine for air. Up here, this can happen depending on which way your hood is pointing when you park your car. If it is pointed into the wind it tends to be a bigger issue. Try parking down wind or do as we do and add a piece of cardboard behind the hood grille with zip-ties and see if that helps. It is strange it is happening on the way home when daytime temps are typically higher. We can experience the cars with autos not willing to even move and the intercooler rubber hoses completely collapsing. Then we have to either find a heat source to warm the engine or just let it idle until it warms up.

NOTE: Don't run the car with the cardboard in place over about +10C/50F and watch your engine temp in traffic.

Neil.

Post by **abscate** » 24 Jan 2025, 11:40

Open up that cap and rotor and inspect for moisture and ice - if you get stuff up in there it behaves badly. While you are fiddling with those cap and rotor screws you can self-flagellate yourself for not buying a 1999 with coil on plugs and a sexy Italian throttle body.

brunocerous · Post by **brunocerous** » 24 Jan 2025, 14:57

scot850 wrote: ↑24 Jan 2025, 11:20 Try parking down wind or do as we do and add a piece of cardboard behind the hood grille with zip-ties and see if that helps. It is strange it is happening on the way home when daytime temps are typically higher. We can experience the cars with autos not willing to even move and the intercooler rubber hoses completely collapsing. Then we have to either find a heat source to warm the engine or just let it idle until it warms up.

I also thought it weird that was only happening on the way home. I let the engine warm up a bit longer today on the way home, and it was a lot better behaved but still not perfect. I'll have to try the cardboard trick. Thank you.

abscate wrote: ↑24 Jan 2025, 11:40 Open up that cap and rotor and inspect for moisture and ice - if you get stuff up in there it behaves badly. While you are fiddling with those cap and rotor screws you can self-flagellate yourself for not buying a 1999 with coil on plugs and a sexy Italian throttle body.

I'll take a look, thank you! The Silver Bullet has a new Italian throttle body (which cost as much to repair as I paid for the car!) but now has a coolant leak I need to track down.

Post by **abscate** » 24 Jan 2025, 23:02

Thank your neighbors who insist on driving into Manhattan for paying congestions fees for me too. I would suggest you drive s different car to the train station and the Volvo back but the Moderators may feel that is less than helpful

Happy New Year, Bruno!