Hi all,

 

I have a 1.2 fabia engine CGPA. It skipped a few teeth on the timing and wouldn't run so we bought all the new parts and did the chain ourselves. New crank/cam sensors, filters, sparkplugs, chain ect.

 

We fitted everything back together and did the timing then tried to start but it wouldn't catch, didnt even sound like it was trying. We checked fuel, purged the rail and could also see fuel on top of the pistons, could also hear the priming when you open drivers door, checked all the coil packs with new/old spark plugs, all working. Cleaned the earths. Tried with the new and old cam/crank sensors. Turns over fine but will not start.

 

We watched some videos and thought the timing was out by 180°. I did some checking and didn't think it was the case as piston 1 was TDC when crank/cams had the locking pins installed. To further verify timing was correct i stripped all the parts off and removed timing cover to make sure the two dots on the cogs are lined up (picture with red circle).

 

Im very stumped over this, thinking its an electrical issue? Cam/crank sensors need resetting? We have a "carly" OBD scanner we have used to reset codes but thinking we may need a proper mechanics scanner to reset. 

 

Any help or advice is greatly appreciated 

The 12-valve engines often suffer valve damage if timing correlation is lost, I'm  afraid.

6 hours ago, Breezy_Pete said:

The 12-valve engines often suffer valve damage if timing correlation is lost, I'm  afraid.

I purchased a borescope and looked down each cylinder, i didnt notice any metal on the pistons. Instead of smashing and breaking would they just be bent?

Compression test would tell you, I think.

Does it seem to crank over fast, and possibly sound unusual while doing so?

Bent valves and low compression?

It doesnt seem to crank over any faster. Yeah i think compression test is the next step. Annoyingly i have stripped it down, am i correct in assuming i will need to turn it over with starter for the test and it cant be done by hand turning the crank?

The compression test will require the engine to be turned at a normal cranking speed.

Further to my above post, if the head is currently off the engine, careful inspection of the valves and seats should establish if damage has occurred - might be well worth replacing valves and lapping seats while the head is off anyway. 

Often a USB-type borescope will have an optional 45° mirror, allowing you to look sideways as well as straight downward. That would probably give enough of a view of valves to see anything grossly abnormal? Can be tricky to see well enough though.

What was original cause of issue - stretched chain, worn sprockets or tensioner failure?

5 minutes ago, Breezy_Pete said:

Often a USB-type borescope will have an optional 45° mirror, allowing you to look sideways as well as straight downward. That would probably give enough of a view of valves to see anything grossly abnormal? Can be tricky to see well enough though.

Tried this and its not good enough to make a judgement unfortunately 

Just now, Warrior193 said:

What was original cause of issue - stretched chain, worn sprockets or tensioner failure?

Stretched chain. It might be worth mentioning that i wasnt driving when it went, i had pulled up to a friends and tried to start car to leave. It started but sounded like it was misfiring. Tried pulling away and there was no power. Pulled up to the opposite side of the road and then left it till the morning for RAC.

Just now, JimmyScoff said:

Stretched chain. It might be worth mentioning that i wasnt driving when it went, i had pulled up to a friends and tried to start car to leave. It started but sounded like it was misfiring. Tried pulling away and there was no power. Pulled up to the opposite side of the road and then left it till the morning for RAC.

I think it jumped on the crankshaft sprocket 

6 minutes ago, JimmyScoff said:

i had pulled up to a friends and tried to start car to leave.

Parked on a hill and left in gear, by any chance?

1 hour ago, Breezy_Pete said:

Parked on a hill and left in gear, by any chance?

No was a flat road, handbrake on