2001 Volvo C70 T5 Rough Idle ProblemRESOLVED skipped TB

VolvoC70T5 · Post by **VolvoC70T5** » 24 Sep 2013, 01:41

Hi,

I have again another problem ( problem after problem with this car ).

My head gasket started to leak, so i changed the gasket ( and head itself as original was cracked heavily), head parts were all changed aswell with new and valve clearance set as specified.

Now, when the car is back together and working, i have problems with boost presure when the engine is idling, normally boost in "N" and "P" was arround -0,7bar, but now it is at cca -0,55 and jumping up and down a little - with rev's jumping up and down aswell - please see video on link. Beside that, car drives fine and pulling same as before all this - boost pressure under full throttle as it should be - only this idle problem has occured. No Engine light or anything else present at any time...

When i put in "D" it also revs up and down.

Before i start tearing apart again i am looking for any advice what to look for if there is any known issue with same problems as mine...

And one more thing worth mentioning - after i started the car this morning ( cold engine ) it was fine for about 5-7min untill it got warm then rough idling appeared back,...

Thank you!

Post by **MoVolvos** » 24 Sep 2013, 19:36

VolvoC70T5 wrote:
Before i start tearing apart again i am looking for any advice what to look for if there is any known issue with same problems as mine...

And one more thing worth mentioning - after i started the car this morning ( cold engine ) it was fine for about 5-7min untill it got warm then rough idling appeared back,..

Thank you!

**

Could it be an ETM issue? Your Youtube link does not work?

Volvo Rough Idle Problems (ETM issues) - how to fix

VOLVO ETM CLEAN / REPLACE TURBO MODELS V70/S60/S80 THROTTLE BODY

If you are going to tear into it again here is a good reference
Volvo 5-cylinder: How to Replace the Head Gasket

Blessings,

BKM

**

VolvoC70T5 · Post by **VolvoC70T5** » 25 Sep 2013, 00:00

Hm, youtube link works from me...strange :/

I kind of ruled out ETM problem as from what i've seen on other ETM problems, everywhere rpm's jump up/down much more (i'd say to cca 500 rpm's up and down ) as with mine i have only 50 or so rpm's up and down while idling. And that was thouroughly cleaned properly before putting back - i never had any kind of smallest problems with idling...

We suspect that there is something with spark plugs...or one not working in idling i gues...mechanic has it now and just working on it.

If anything esle fells on mind....let me know.

Thanx!

VolvoC70T5 · Post by **VolvoC70T5** » 25 Sep 2013, 10:12

Still having same issues

We tried today:

-Changed new spark plugs - it worked for 20 min than the problem came back
-Changed all 5 coils ( the one which comes over spark plug ) - no difference at all, still same problem
- Then we tried to change vvt crankshaft sensor - it was immediatelly OK but the problem came back after 3kms of driving
- Tried to shake all the cables for spark plugs etc but without effect if there would be some loose contacts or anything - no effect

Anyone had same problem? PLEASE i am begining to become desperate...

VolvoC70T5 · Post by **VolvoC70T5** » 27 Sep 2013, 10:34

So, the problem has been solved if anyone comes across.this alike issue....

It was missed timing for one tooth on exhaust crankshaft...