'04 XC Engine Misfiring-Further Updated (Moisture ruled out - possible defective coils, bad MAF) Topic is solved

Post by **E Showell** » 10 Jun 2020, 11:02

The new coils all had new boots. I did not detect any holes or tears on the plug boots when I swapped them around.

More and more I am thinking failed MAF.

Ran like a champ when I pulled the MAF electrical connector, but I am not getting any MAF-specific codes on VIDA.

boet · Post by **boet** » 10 Jun 2020, 12:07

May be check the wiring from the coils to where it connects into the main loom connector.

boet · Post by **boet** » 10 Jun 2020, 12:11

Have you got a wiring diagram ?

Post by **E Showell** » 10 Jun 2020, 12:36

No, I do not. Electricity and wiring aren't my strong suits either.

Post by **E Showell** » 12 Jun 2020, 16:34

Replaced MAF with new purchased from FCP (none available at Harry's). Problem solved.

Post by **RickHaleParker** » 13 Jun 2020, 01:37

E Showell wrote: 12 Jun 2020, 16:34 Replaced MAF with new purchased from FCP (none available at Harry's). Problem solved.

Last month I cleaned the MAF electrical connector on my S40. Misfiring problem solved.

Post by **E Showell** » 13 Jun 2020, 04:12

So, not solved. Son went to use car for work this morning. Lumpy idle back. I'm going to have to put VIDA back on the job and see if I can glean any more useful data. Bad throttle body?

Pulled two throttle bodies at Harry's yesterday, but part numbers don't correlate to what FCP says I need. Ones I pulled end in "53". FCP says I need a "54". Last one I pulled came from the same model and year and had a completely different part number (starting in "36") than the FCP part number. I did not keep the 36 since it looked really beat. Another source suggested they were all interchangeable. Thoughts on that?

And just so you don't think I am a complete idiot, the "53" throttle bodies I did pull both had original Volvo markings on them and both came from cars FCP said should have had the "54" throttle bodies per their fitment guide.

Also, I would be eternally indebted to anyone who can tell me how the throttle body wiring harness clips work. In the three throttle bodies I pulled at Harry's, I utterly destroyed the clips to get them off. Could not for the life of me loosen them for removal.

Post by **abscate** » 13 Jun 2020, 04:55

The intermittent nature of this is making me think throttle body.

Headed to NY this morning, will noodle on it

VIDA will tell you about throttle action of course

Post by **E Showell** » 13 Jun 2020, 13:54

VIDA back on it.

No misfire codes. Faulty throttle code.

Sort term fuel trim both sensor banks at zero (open loop). Long term trim both banks at 99%. Not sure what all that means as it relates to throttle, but VIDA readout said idle rpm at 200.

This looks like a throttle body problem to me.

Post by **RickHaleParker** » 13 Jun 2020, 16:26

E Showell wrote: 13 Jun 2020, 04:12 In the three throttle bodies I pulled at Harry's, I utterly destroyed the clips to get them off. Could not for the life of me loosen them for removal.

Spray them with WD40 and let it soak down in between the two plastic connectors. Most of the time they slide apart afterwards.