My 98 V70 2.5T M56 is giving me some troubles.
Quick recap: 2 months ago, I bent two rods in my engine due to a tuning mistakes. The engine was knocking but running. Took it out of the car and as I couldnt find a spare engine, bought an entire 1998 C70 with the same engine but automatic (slightly younger because it has the mechanical belt tensionner, but still M4.4).
Drove the C70 back home for an hour. Pulled the engine, did a timing belt, camseal behind the distributor and dropped it back into the V70.
My issue is that the car doesnt start, it tries to catch, pops a bit for a second or two then stalls again
What I have done so far:
- checked fuel pressure at the rail, holds around 50psi even when cranking
- with a spark plug touching the block I can see it sparking in daylight
- MAF plugged or unplugged
- swap the cam position sensor
- swap the crank position sensor
- check the timing
- swap the distributor cap/rotors and check position (timing marks aligned, spark going to cylinder 1) + double checked the wire position
- ran an extra ground wire straight from the battery to the engine block
- checked compressions of the first 4 cylinders (getting the 5th plug wire with the charge pipe is a bitch, and i was lazy
), they're healthy- two ECUs with different maps (one being based on the NA market map, so doesnt care about the immo)
- test the injectors plugs by using the C70 fuel rail injectors (mine arent Volvo specific greens so I had to delete the bracket that holds them to the rail, they pop off under pressure when the rail isnt bolted to the intake), they sprayed fuel
- two batteries, and I measured 12.5V between the + post and the engine block
What bothers me:
- ECU had a code for "ECT Signal missing", this seems it could keep the car from starting. But I've tried the my other sensor, doesnt make a difference. The ECT plug is getting 5V so I dont think there's damage to the wires coming from the ECU. Also the OBD gives a very believable value for engine temp.
- OBD infos says the timing advance is 79 degrees ! A quick search says these engines usually dont go over 35/40. I've heard some backfires through the intake a few times, so the plugs firing at the wrong time doesnt sound impossible to me
But why ?? Theories I have left at this point:
- CPS not picking up the flywheel teeth properly ? I didnt change the bracket, only the sensor. Maybe it's different between auto and manual ?
I dont see how I could have put the flywheel wrong, it's keyed
- bad fuel ? I know E85 doesnt like to sit but it's only been 45 days and it has been very dry
- unhappy volvo gods
I'll take any suggestion, because I'm really running out of ideas now
On that, I'm going back to browsing old threads and coming up with new theories every 5 min just to scrap them later
)
