99 V70XC misfire coil codes

nisan17 · Post by **nisan17** » 16 Aug 2017, 21:12

Hi Group,
It's been a while since I've been on. Well, over a year ago(march 2016) I bought a 1999 V70 XC 2.4 turbo. It has run like a top till the end of July 2017 when it started missing. I took it to AutoZone and the OBDII scan showed a hard miss in #1. I replaced all plugs(to spec) and all coils, ebay aftermarket. Now, I'm getting codes saying it's missing in all cylinders, bad coils. P0301, P0351; P0352; P0353; P0354 and P0355

Is there something else I'm missing? I'm almost at the wall! I'm getting my injectors cleaned tomorrow to eliminate that.
Since this has started I've I've gotten the "FIXD" OBDII bluetooth scanner which works very good by the way!

Thanks much in advance,

Post by **scot850** » 16 Aug 2017, 23:00

Could well be crap aftermarket parts. I have even had a DOA coil from Volvo. At least it was replaced without hassle.

I would check the engine ground wires and remove the coils and look for hairline cracks under the rubber boots. That from what others tell me does not mean they are not going to work but can lead to shorts/misfires. I'd also take a look at the wiring to the coils as that can become brittle.

When you remove the coils, make sure the seat/post the hold-down bolt goes into is clean as is the coil post, before re-bolting it back down. Torque then to correct spec. Over tightening can damage the coils.

Neil.

Post by **precopster** » 17 Aug 2017, 03:00

You could just get one used coil from parts wrecker and see if that eliminates that cylinder. If it does you would be pretty right in presuming crap aftermarket coils.

There are 2 grounds on the cylinder head close to where the coils are located as part of the coil loom.
Check those grounds for corrosion.

nisan17 · Post by **nisan17** » 17 Aug 2017, 08:50

Well, just got back from the car shop and they did a compression test. #1 has zero compression; #2 has 50lbs; #3 has 75lbs. They stopped checking as the numbers were just getting higher.

Hard too believe as there were no gradual symptoms. The misfire just happened one day while driving. Never smelled fuel prior or since. I'm going to just do my own leakdown tests.

Any other ideas? This would be greatly appreciated.

Post by **abscate** » 17 Aug 2017, 15:39

Confirm the compression results as they are fatal engine results , of course

nisan17 · Post by **nisan17** » 17 Aug 2017, 18:09

Exactly my plans this weekend. No gas in the oil. No oil in the antifreeze and vice versa. No over heating. Right now, plans are to do the compression testing myself. I have a strong suspicion it's a burnt valve.