2001 S60 2.4T: Car dies upon start, can't idle or run

[TonyS60]

My sister was driving our 2001 S60 2.4T to work yesterday when the car began to slow while she was still trying to maintain speed on the highway. The car eventually slowed to a point where she had to pull off the road. She took her foot off the gas to hit the brakes, the engine died. When I arrived I tried jumping the car but that didn't seem to be the issue, as the car would start but then dies if the gas pedal isn't pressed. We managed to get the car home, but the car would not go over 15mph ("limp mode", I assume). It wasn't easy as the gas pedal could not be released for more than 2 seconds (probably less), otherwise the car dies. Once we got the car home, I plugged in our OBD-II scanner and received the P0304 code, "Cylinder 4 Misfire Detected".

Today, my father and I were looking into the car and what the problem could possibly be. We pulled the 4th cylinder ignition coil and spark plug out, and they looked clean but we weren't sure how to bench test a COP ignition coil. My dad tried using a multimeter on the 4th and 5th ignition coils to see if there was any difference in resistance, but the only reading he could get from either was infinite ohms. During removal of the 5th ignition coil, he discovered that the anchor bolt had been tightened while the black wire (believed to be the ground wire) from coil #4 was partially under the bolt resulting in pinching the wire. The pinch point cut through the outer insulating jacket and cut some of the strands. However, if this is a ground wire that should not have had any impact on the performance. If it is not the ground wire, I don’t know if it may have caused damage to a component that could be causing, or at least contributing to, the symptoms. Since most of the wire strands were intact, my dad taped over the damaged insulation jacket and we put both ignition coils back in.

After clearing the code, hoping it would clear limp mode, we tried starting the car but nothing changed. Unless you apply the gas immediately upon the engine turning over, the car just dies. When applying the gas to get around 1200rpm, we get a rough idle. Once the engine reaches around 1800-2000rpm however, the engine starts revving higher and steady (up to 2500rpm max); even if I'm backing off the gas at this point, rpm continues to rise.

After plugging in our OBD-II again, we now received the codes: P0300, P0301, and P0302. Additionally, the scanner read under the I/M section, that the following were not ready: CAT, EVAP, 02S, H02S. Last night, everything under I/M was "ready".

We've been looking around the internet, and saw that this could be related to the ETM, which had a software recall in late 2005. Looking at service records, our ETM software was upgraded in July 2006. So do we need to clean the throttle body? We watched the video about cleaning it in the "Idling then dies. IAC valve? 2002 S60 126k miles" post, on this site.

Can somebody advise if this is how we should proceed next? Or is there something else we should try first? My dad additionally checked the fuel rail pressure, which is plenty strong (my dad immediately reeked of gasoline after checking that). Because the OBD codes went from 304 to 300, 301, and 302, we're no longer sure what to do about ignition coils or how to proceed.

Any advice would be greatly appreciated. Thanks!

[anjill182]

Make sure all of your intake hoses are good and attached.

[TonyS60]

My dad said he hasn't checked all of them, but the ones that he did look at were all perfectly fine. He's been busy with the throttle body and is putting it back in now that he's cleaned it; it definitely needed a cleaning, that thing was filthy.

[537playing]

I would suspect a bad MAF sensor. The sensor is between the air filter box and the throttle. Just unplug it and run the car. If it runs! Then that sensor needs to be replaced. Try this first as it won't cost anything.

[chilcoja]

Just replaced the ETM on my 2001 S60 Turbo to eliminate the "Limp Home" issue. I initially suspected the transmission slipping, but indications were that I was pressing the gas pedal down with no corresponding increase in engine RPM's. I used the XEMODEX retrofit to avoid having any issues in the future. All seems well. If the hose to the turbocharger air heatexchanger is loose, this can cause rough running and failure to idle.