V70 bifuel problems

[MrP]

hi,

as per usual, my V70 bifuel is giving me problems.

its just had its 106,000 mile service, and i asked them to replace the spark plugs, however i'm getting a misfire when i first press on the accelerator.

i had my local indie check the coils and they said they are showing no sign of "breakdown" but i have no idea how they checked them or what they mean by that.

as far as i can tell the car is throwing no unusual codes according to my reader (one of the BSR jobs) however the engine light is on and i cant get it off (the stored codes are for the climate control and the head unit missing as far as i can remember)

so is there anything i can try myself before ordering myself a coil and just changing them over in hopes of fixing it?

cheers

[Hewey]

Hi,

There are the resistance limits for primary and secondary coils in a coil unit. But I doubt that they tell you much about the real condition of the coil unit. I measured mine when I started to have misfires (at about 200,000 km) and all of the coil units seemd to be in specs. Then the misfires were getting worse and finally when cylinder 1 refused to fire at all, I finally believed it was time to buy some new coils.

Since it started to run ok after the cylinder one coil unit change, I thought that it was best to renew them all at once so there would be no hassle with coils anymore. Afterall they were not so expensive. I wish I had changed them a lot earlier since the catalysator took too much damage when I had to drive the car home with the one dead coil. A new Volvo catalysator was really expensive.

Regards, Hewey

[classicswede]

No need to buy coils at this stage. You can find out by reading the missfire code and idenfify what cylinder is missing. Swap the oil off taht to another cylinder and if teh fault moves with it you have found the problem. If the oil is teh fault change all 5.

If the fault does not move then start looking at other things. If this has only started after service have they put the correct copper core plugs in?

[MrP]

i've got one of those BSR code readers, but it dosent tell me i have a misfire, in fact t cant even put out the engine management light at the moment

i had the plugs changed about 12,000 miles ago as it was midfiring them and i found that the indie had put multi core plugs in, so we swapped them ou for bosh single core plugs which solved the misfire, however it returned before the service and its still there

[classicswede]

Start with the cheap option and put in a set of NGK BKR6ES plugs. At least that will eliminate them as a problem.

[MrP]

right, just been out to reads the codes again!

first time through i got CCM 0021 and CEM 1A59 (air quality sensor, communication with AUM) second time the engine was running and i got the same 2 as well as ECM 3503 (misfire, at least one cylinder, cat damage!)

[capt jack]

I've found with my V70 LPG conversion that at best the plugs will last around 10,000 miles, at which time I start getting a misfire at 3000rpm under moderate acceleration.

Bosch superplus or Denso plugs - always copper-core single point - last longer than anything else. Multi-points are a complete no-no.

Cheers

Jack

[MrP]

i've always had a problems with it "leaning out" but now whenever i put my foot on the accelerator (be it lightly or heavily) i get 3 or 4 seconds of misfirig before it sorts itself out, and carries on being its usual useless self.

[FatLadZ]

had the same thing
i changed .....

Plugs x 3 times
3 coils
air mass meter
inlet air tempreture sensor
coolant temp sensor

then finally i gave in and admitted what id feared all along.....
The dreaded ETM
had it fitted on saturday and now the car is amazing

[FatLadZ]

by the way removing the car battery for 10 mins and then reconnecting it sorted it out for that run and the next run then it would revert back.
at no point did i get the ets light on