1.8t - does good compression eliminate HGF?

badrover · 26th February 2015, 17:38

I'm still having trouble with my 1.8t. It's been off the road for February whilst I scratch head over what is the problem.
It started misfiring on cold start up (9 times out of 10 anyway) so I replaced the IMG. This made no difference so I replaced it again, still no change. So, I removed the inlet manifold again, checked it and the head with a straight edge, put another new gasket on, torqued it back up in the correct sequence, still no change. Throughout all of this, it's thrown up misfire on cylinder 3 on the OBD. When removing the plug, sure enough there have been traces of coolant in the cylinder. The compression test reveals readings of 175, 180, 180, 185 (cold).
Do these good readings eliminate HGF?
I would like to fix it for good and get it taxed for March but I don't want to risk hydra lock (is that possible) or ruining the turbo with coolant.

rrobson · 26th February 2015, 18:09

Have you checked the coil packs?

Also, is the coolant becoming discoloured?

badrover · 26th February 2015, 18:15

Thanks. Coolant is very clean and there's zero Mayo under either filler cap. There's no excessive exhaust steam and it runs very well indeed once the misfire clears after 5 seconds or so. Perhaps I should swap the coil packs and see if the misfire swaps cylinders.

HenryD · 26th February 2015, 18:45

If you have signs of coolant in the affected cylinder its either the IMG which you have eliminated or the head gasket is leaking or worse still liner or head damage,coolant can't Get into a cylinder by any other means so its head off next to inspect gasket or have the head pressure tested if no gasket fault found.

T-Cut · 26th February 2015, 19:09

A failed IMG allows coolant into cylinders 1 and/or 4 only, so it must be getting into No3 by another route.

TC

badrover · 26th February 2015, 19:13

That was one of my thoughts re cyl 1 and 4. Off with its head then I guess. The engine hasn't done 20k yet and I have a digital coolant read out that I watch like a hawk. It's never overheated so just rotten luck I guess.

DMGRS · 26th February 2015, 22:15

It sounds very borderline to me - I'd be careful about a diagnosis of HGF.
If you do find it is though, I have a good selection of kits for the K Series here - Head Gasket Kits- K Series

Usually when HGF occurs between a cylinder and cooling system, you get a lot of pressure in the cooling system from leaking exhaust gasses.

minimutly · 28th February 2015, 14:58

Sounds like you have a cracked liner or a crack in the head. Need to inspect carefully. It may even be a crack into inlet or exhaust ports, very unusual, but possible.
Huw

badrover · 28th February 2015, 16:19

Thanks for the advice. It's only done 22k miles so I'm hoping it's not a cracked liner which would be a new engine job. It's always had 50/50 OAT, has been driven very steadily doing motorway miles only and has never overheated. I fitted an ezee digital readout, which I watch like a hawk and it's never got hot. Fingers crossed it's just the gasket. Ive got a recommended mobile mechanic to do the job. He's going to ring on Monday to arrange.

minimutly · 28th February 2015, 16:52

No, you're wrong, cracked liner is no bigee, you need to drop the sump to change one, but it's pretty easy, in fact, withe the right ring compressor you could do it without dropping the sump, I need to look into that.
Agree with a previous poster, your head gasket should not have failed as soon, or at all, unless you have an overheating episode.
Huw

26th February 2015, 17:38	#1
badrover Gets stuck in 75 club se tourer,75 cdt tourer connie se, 75 dealer launch Join Date: Jan 2013 Location: cheshire Posts: 536 Thanks: 79 Thanked 97 Times in 73 Posts	1.8t - does good compression eliminate HGF? I'm still having trouble with my 1.8t. It's been off the road for February whilst I scratch head over what is the problem. It started misfiring on cold start up (9 times out of 10 anyway) so I replaced the IMG. This made no difference so I replaced it again, still no change. So, I removed the inlet manifold again, checked it and the head with a straight edge, put another new gasket on, torqued it back up in the correct sequence, still no change. Throughout all of this, it's thrown up misfire on cylinder 3 on the OBD. When removing the plug, sure enough there have been traces of coolant in the cylinder. The compression test reveals readings of 175, 180, 180, 185 (cold). Do these good readings eliminate HGF? I would like to fix it for good and get it taxed for March but I don't want to risk hydra lock (is that possible) or ruining the turbo with coolant.

26th February 2015, 18:09	#2
rrobson I really should get out more....... 75 tourer cdti, MG ZS 180, nissan terrano & 1.8t rover 25 Join Date: Feb 2010 Location: Pontefract Posts: 2,644 Thanks: 17 Thanked 295 Times in 218 Posts	Have you checked the coil packs? Also, is the coolant becoming discoloured? __________________ How to view a car - everything you need to help you inspect a used car VIS motor tester avalible to local members Injector removal tool and auto gearbox pressure tester now available

26th February 2015, 18:45	#4
HenryD Loves to post MG ZTT Join Date: Feb 2014 Location: Helston,Cornwall Posts: 371 Thanks: 64 Thanked 45 Times in 42 Posts	If you have signs of coolant in the affected cylinder its either the IMG which you have eliminated or the head gasket is leaking or worse still liner or head damage,coolant can't Get into a cylinder by any other means so its head off next to inspect gasket or have the head pressure tested if no gasket fault found. __________________ 2003 MG ZTT Cdti in Trophy blue other rides are a Touareg 2.5tdi,Focus Zetec and a Pug306 cabrio

26th February 2015, 22:15	#7
DMGRS Discount MG Rover Spares Rover 75 CDTi, 2x MG ZS180 Join Date: Jun 2011 Location: Hythe, Southampton Posts: 11,320 Thanks: 456 Thanked 3,377 Times in 2,027 Posts	It sounds very borderline to me - I'd be careful about a diagnosis of HGF. If you do find it is though, I have a good selection of kits for the K Series here - Head Gasket Kits- K Series Usually when HGF occurs between a cylinder and cooling system, you get a lot of pressure in the cooling system from leaking exhaust gasses. __________________ Your trusted MG Rover specialist! Tel: 02380 001133 / Email: [email protected] We now have a 'chat' function on our site for even quicker replies. Give it a try! Remember - discount code FORUM5 for 5% off

28th February 2015, 16:19	#9
badrover Gets stuck in 75 club se tourer,75 cdt tourer connie se, 75 dealer launch Join Date: Jan 2013 Location: cheshire Posts: 536 Thanks: 79 Thanked 97 Times in 73 Posts	Thanks for the advice. It's only done 22k miles so I'm hoping it's not a cracked liner which would be a new engine job. It's always had 50/50 OAT, has been driven very steadily doing motorway miles only and has never overheated. I fitted an ezee digital readout, which I watch like a hawk and it's never got hot. Fingers crossed it's just the gasket. Ive got a recommended mobile mechanic to do the job. He's going to ring on Monday to arrange. Last edited by badrover; 28th February 2015 at 16:25..

26th February 2015, 18:15	#3
badrover Gets stuck in 75 club se tourer,75 cdt tourer connie se, 75 dealer launch Join Date: Jan 2013 Location: cheshire Posts: 536 Thanks: 79 Thanked 97 Times in 73 Posts	Thanks. Coolant is very clean and there's zero Mayo under either filler cap. There's no excessive exhaust steam and it runs very well indeed once the misfire clears after 5 seconds or so. Perhaps I should swap the coil packs and see if the misfire swaps cylinders.

26th February 2015, 19:09	#5
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	A failed IMG allows coolant into cylinders 1 and/or 4 only, so it must be getting into No3 by another route. TC

26th February 2015, 19:13	#6
badrover Gets stuck in 75 club se tourer,75 cdt tourer connie se, 75 dealer launch Join Date: Jan 2013 Location: cheshire Posts: 536 Thanks: 79 Thanked 97 Times in 73 Posts	That was one of my thoughts re cyl 1 and 4. Off with its head then I guess. The engine hasn't done 20k yet and I have a digital coolant read out that I watch like a hawk. It's never overheated so just rotten luck I guess.

28th February 2015, 14:58	#8
minimutly Posted a thing or two mg zt Join Date: Mar 2014 Location: cardigan Posts: 1,087 Thanks: 28 Thanked 187 Times in 158 Posts	Sounds like you have a cracked liner or a crack in the head. Need to inspect carefully. It may even be a crack into inlet or exhaust ports, very unusual, but possible. Huw

28th February 2015, 16:52	#10
minimutly Posted a thing or two mg zt Join Date: Mar 2014 Location: cardigan Posts: 1,087 Thanks: 28 Thanked 187 Times in 158 Posts	No, you're wrong, cracked liner is no bigee, you need to drop the sump to change one, but it's pretty easy, in fact, withe the right ring compressor you could do it without dropping the sump, I need to look into that. Agree with a previous poster, your head gasket should not have failed as soon, or at all, unless you have an overheating episode. Huw