Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[BazaJT]

This is on my step daughters 2001 Volvo C70 with a 2.4 low pressure turbo petrol engine and manual gearbox.Sometimes it will start straight away but most of the time the engine will turn over and occasionally "lock up" [as though a cylinder is flooded]for a split second before continuing to turn over.Once it does start it ticks over evenly and revs cleanly driving exactly as it should.Reading the codes with a cheap reader brought up P0014[cam timing advanced]but the car shows none of the running issues associated with that code.The rear [exhaust?] cam has a hub [vvt?]on it.We've fitted a new crank sensor to no avail .When cranking the rev counter needle will at times flick from zero to about 2,500 revs before instantly dropping back to zero but it doesn't do this with any regularity.Firing the parts cannon at it is not an affordable option. Any ideas as to where/what to look at? TIA.

[dave the builder]

have you checked the basics ?
known good battery ,cleaned the earth points etc
checked the voltage when cranking 

[Nick W]

If presented wth a cam timing fault code, I would be physically checking it. Yes, I know that's not simple.

[Viral_Jim]

have you checked the basics ?
known good battery ,cleaned the earth points etc
checked the voltage when cranking 

Suspect Dave maybe on the right lines. This thread suggests it may be a problem with the contacts around the starter motor causing the tachometer to spike....

https://www.swedespeed.com/threads/tach-spike-on-startup.197928/#:~:text=its%20a%20common%20problem%20the,could%20be%20bad%20if%20OK.

[BazaJT]

Battery is a known good one,but haven't checked cranking voltage or earths I will check these when next I get the opportunity{which should be within the next week weather permitting]
Yes checking the timing marks is a faff but will add that to the list.
Hadn't thought of starter motor connections will check those and if necessary substitute the starter off my V70[basically same engine only mine is not turbo'd] if they're the same to prove it one way or the other.
Just as a precaution I'll also check the antenna ring connections.
 Thanks for the replies/ideas guys,at least now I have some areas to investigate and see where we go from there.

[Marks DTM Calib]

If the rotation is stopping and then restarting during cranking then it points to either a physical lockup, or an electrical starter issue.

So checking grounds and positive connections is a good start, could also be a burnt segment on the starter comm (although less likely as you expect it to have slightly bigger issues like failure to turn over at all if the brushes are on the problem segment at start).

Mechanically, is it using any coolant ?

[BazaJT]

Yes it does lock up sometimes during cranking only for a split second before continuing to crank. It doesn't use any coolant or oil. Will check earths and starter.

[cam.in.head]

sounds like you need a diagnostic tech who can use a scope . he should scope the starter main power feed and the casing to check for any power or earth dropouts during cranking.if there's a bad connection this will show up .
obviously if nothing shows then a current test and simulated cranking compression test should show any issues internally with the starter or otherwise .
that's the basics out of the way . after that it would be nice to see the actual crank and cam angles

[Doctor Gollum]

You could first check/clean/replace the connections between the starter, battery and ground