Cant get MOT help

Hi all,

I put my 4.0 V8, P38 Rangie which has covered 145000 miles on the original engine, in for a MOT this week and it failed on CO2 being way two high and not by a bit. reading around the 8.6 and need to get it below 0.3.

So after getting it back to the workshop and giving the engine a good going over. I have changed all the filters, oils, plugs and leads. etc. pluged it in to Autologic and made sure all the sensors are reading right and doing what they should be. I still carnt get the emissions down. If you let the engine get to operating temp and start to bring the revs up slowely at about 2000 - 2200 revs I am getting a thick blue haze out of the exhaust. But if I hold the revs a 2200 for a min or so it does clear.

My first thought was If I had a set of piston rings not sealing and it was consuming engine oil. So have done a compression test on a cylinders and they are all within the 10% limit.

So I dont think its rings. I have added a fuel flush just incase to try and improve things but to no joy.

Slowley running out of ideas.

Can anyone help shed some light on possable causes or areas which I can look into.

Many Thanks

Bryan

You say you plugged it into Autologic,did you monitor the activity of the oxygen sensors ? Blue smoke indicates oil consumption - for it to reach the combustion chamber it needs to get past the piston rings or valve guides,or both.
145,000m is plenty for an LP v8 motor,I think you may need to consider a rebuild,please give more accurate info of the live data that you saw on Autologic.

Hi all,

Had a tinker with the rangie over the last few days. I am now convinced its not engine oil coming out the exhaust.

I have developed a bit of a misfire at around 2000- 2500 revs. on removing of the spark plugs I found that no.2 cylinder the plug had completly oiled up. I thought it may be one of the coil packs but. I would expect to have two cylinders miss firing. Could all the the problems I am having with emishions be down to a leaking injector?

Has anyone else come accros injector problems in the past. Is there anyway of testing them.

Many thanks

Bryan

I have a 97 4.6 HSE P38 now, but used to have a 94 Classic ... My emissions on the latter were up at 5.0. Now I am no expert on cars of any kind, and prob the least technically gofted on this site, but my local MOT man said it was prob the fuel meter. If it is the same set up on the P38"s, then this may need adjusting. If not possible to adjust, then replace, but they can be costly according to my man ....

P38 Owner said:

Hi all,

Had a tinker with the rangie over the last few days. I am now convinced its not engine oil coming out the exhaust.

I have developed a bit of a misfire at around 2000- 2500 revs. on removing of the spark plugs I found that no.2 cylinder the plug had completly oiled up. I thought it may be one of the coil packs but. I would expect to have two cylinders miss firing. Could all the the problems I am having with emishions be down to a leaking injector?

Has anyone else come accros injector problems in the past. Is there anyway of testing them.

Many thanks

Bryan

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injectors dont normally play up, if the plug is oiled then your engine must be using oil (rings etc.)

are you sure it was oiled or just black as in rich mixture? if the mixture is rich then i'd suspect the air flow meter or blocked air filter.

are the o2 sensors switching accross their full range? they may be working but not working enough

Hi all

Spent some more time on the rangie today, I substituted the injector which I thought was playing up, Took it for a long run. and it made no diffrance. It does go better but still smokes at high revs.

Clutchdust...

Checked out the o2 sensors and they are switching accross there full range. Just had a new air filter. I would expect to get black smoke out the back if it was overfulling, much like running a petrol landy with the choke out?

So tomorrow off with its heads!!. I have removed the rocker covers today and it is spotloss. It has had new rocker shafts and rockers at some point reason unknown.

I will let you all know what I find hopfully not damaged rings and bores or the engine will be remachined, top hat liners the lot. But fingers crossed it will only be valve and head work. Might stand a chance of getting her back on the road by the end of the week.

I do like my P38A but how complicated did Land Rover have to make this product.

Bryan

good luck bryan i am watching this post with interest as my mot is due and it is running well rich regards dave

Hi all,

Heres the latest, Today I have streiped the heads of the rangie. after close inspection of the bores and the valve stem oil seals I was unable to find a sorce of the oil entering the bores.

So at present I am putting it down to the fact that the engine has been abused some time in its life and is in need of a good overhaul. So will be removeing all pistons and giving the engine a rebuild.

One thing that did concern me was I needed to but 450 foot pounds of torque to remove the head bolts on bank 2. I think it must have been assembled by an animal!!.

I have started to rebuild the heads today so give it a few days and they will be ready. Can anyone tell me the tolarence on the flatness - twist allowance the heads. Looks like I have got 0.1 - 0.125 on one of them.

I will be preasure testing the block this week as it has not had top liners fitted and if they leak the whole lot will be sent for machining.

Dave......

Good luck with your MOT. Im sure you wont have as many problems as me.

Keep you all posted.

Bryan

just a little tip if you haven't already passed that stage in yer overhaul yet, just pour a little petrol into each cylinder and see if it runs down into the oil, leave a few hours and you will be able to see if its dropping into the oil, if so the oil is obviously coming up the oposite way

P38 Owner said:

Hi all,

Heres the latest, Today I have streiped the heads of the rangie. after close inspection of the bores and the valve stem oil seals I was unable to find a sorce of the oil entering the bores.

So at present I am putting it down to the fact that the engine has been abused some time in its life and is in need of a good overhaul. So will be removeing all pistons and giving the engine a rebuild.

One thing that did concern me was I needed to but 450 foot pounds of torque to remove the head bolts on bank 2. I think it must have been assembled by an animal!!.

I have started to rebuild the heads today so give it a few days and they will be ready. Can anyone tell me the tolarence on the flatness - twist allowance the heads. Looks like I have got 0.1 - 0.125 on one of them.

I will be preasure testing the block this week as it has not had top liners fitted and if they leak the whole lot will be sent for machining.

Dave......

Good luck with your MOT. Im sure you wont have as many problems as me.

Keep you all posted.

Bryan

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hello bryan
your having fun at the moment arn`t you , your engine the problem sounds very much like an oil ring problem if the bores are in good order , no obvious damage to the pistons , then there`s not much else left , if an oil ring or scraper ring is broken or stuck into the groove then the engine will burn oil but show no other symtoms hope this helps mate have fun .
rick

wouldnt worry about it too much i`ve not had an mot for nearly a year!

Hi all,

Sorry for the long reply on the update I have been coming to terms with the big bill which is pending.

Anyway with the heads now completly rebuilt with new valves, oil seals and rocker gear. It is time to tern my attention to the block assembly.

Two out of the eight cylinders have a step in the bore (not good) One of the cylinders has got now cross hatching left and six of them are about 8 thou out of round. So I have come to the conclusion that my oil burning problem which started this all off is due to wear and tear on the engine. The possability of rehoning the bores and fitting new rings is also now out of the question. On the plus side I have had the block on pressure test for a week and its as dry as a bone around the linners. Not bad for the original engine on 145K miles.

The engine is now out ready to be striped.The next stage is for it to go off for machining. That way I will end up with. New Top Hat liners. new Pistons, Crank, completly reground including all bearings. They recon around 2 weeks so while thats being done I can get on with some of the other jobs on her.

I am planning to fit a RPI High lift cam, followers and timing gear on my new engine. Has anyone had any experience with these kits?.

I have already started to get all the little bits and pieces, Oil cooler hoses, gasket sets, Front cover with oil pump and Nuts bolts etc. Starting to look like christmas. (boxes everware).

Why the engine is out also decided to fit a new flex plate as this will put another landrover fault to bed.

Will keep you all upto date on the build.

Bryan

hi bryan hows the build going? mine failed the mot today on emmisions
they were 2.6 instead of the 0.3 the mot guy says this is sky high and may have trouble getting it down he is going to change oil/filter and put a treatment through it, but says dont hold your breath as it is very high, so i may end up down your road !! mine is a 4.6 96, 130,000 miles on the clock it sits at a measely 12mpg however you drive motorway the lot??
the quad exaust always is sooted up and you can smell the richness in the exhaust fumes.......... waiting for the dreaded phone call regards dave

With a Co reading that high an oil/filter change and fuel treatment are a complete waste of time.If it is running that rich the oxy sensors are not switching - you need to get it to someone who understands Efi - closed loop systems.
Good luck,dont let them charge you for "fuel treatment" - its a waste of time,will give more help later if you need it,going out for a Curry/Booze now !

a quick update the garage as changed the oil/ filter/ plugs/ and the emissions are ok but the lambda test as failed so 2 new sensors are going in hopefully that will be it otherwise its the cats.......i will repost when they try the new lambdas regards dave

Hi all,

Dave sorry to hear about yours. I treid the lot to try and get mine through but the best product I would recomend is a forta gas treatment. chuck one in a full tank of fuel and you will notice the diffrance. Basicly it cleans all the fuel system including injectors. De-carbonises the cylinders and cleans the cats. This is a very good product and I would recomend it to anyone. I have used this on all my landys and is great.

However this is the first time using this product which has caused me to rebuild the engine. It has done just what it says. but in cleaning the cylinders it washed out all the deposits which ment my rings wernt sealing.

But the update so far is............

I have picked the engine up from the machinests and they have done a excellant job. This is the second 4 litre they have done and it is spot on. Tonight I have fitted new camshaft bearings and the new camshaft. I have also replaced all the core plugs. Might as well as the engine is out. I am going to fit the new crank and pistons tomorrow. along with shells.

I have fully rebuilt the heads and they are ready to go on.

I have more Land Rover boxes then I can shake a stick at and its like christmas LOL.

I have put my last order in for bits today. You dont reliase just how complex the Rover V8 is until your looking at the parts diagrams and ordering bits as required.

My retest is booked for next Friday 29th. I want to put some miles on her first. As im not keen on MOT a brand new engine. So it needs to be back together by Wednesday at the latest. I have got a weeks holiday planed for next week. I see some long days happening.

Dave, you said your only getting 12mpg from yours seams very low. Okay you said you do a lot of motorway miles but thats when there at the most economical. especialy with cruise control on. Unless you have a rather heavy right foot!!.

The garage which has yours, are they kitted out with Autologic or Rovacom? How have they come to the conclusion it was lambers? I hope its not cats as they are mega bucks Modern day cats are a lot more tollarable to abuse. In the early days they were very fragile and as such got a name for them selves. You may want to look at the induction side of things airflow meters etc.

Good luck. I will be interested to hear the outcome.

Bryan

dave121 said:

a quick update the garage as changed the oil/ filter/ plugs/ and the emissions are ok but the lambda test as failed so 2 new sensors are going in hopefully that will be it otherwise its the cats.......i will repost when they try the new lambdas regards dave

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Your garage needs to be more careful what it tells you,if the lambda sensors,(oxygen sensors) have failed there is no way it could pass an emissions test.The engine ecu determines the fuel mixture and therefore the emissions as a result of info the oxygen sensors feed back to it - hence the term closed loop fueling.It all needs to be in place and working correctely to have any chance of passing the full cat type emission test.
Sorry to go on about this,but I hate the mis-information given to customers by garages that dont understand how it works - and end up fitting parts that are unecessary or dont work.

thanks eight for that , i thought it was a bit wierd when he said it has passed the emmisions but the sensors are bad? i will mention that to him next time we speak .
as far as i know bryan he only has 2 crypton machines it was one of them that showed no output on the sensors he said he disconnected them and there was no difference in the readings!
my sensors were changed 3 years ago acording to me service history mmmm i am doubting this guy now, i will def ask for my old ones back
good luck with the rebuild it must be nice to think you will have a great tight engine soon , regards dave

Hi Dave,

been giving your problem some fort and you dont have LPG fitted to your rangie do you?

I only ask as the LPG hotwire system picks a feed up of one of the lamber sensors. I have seen it before and to get it through emmissions we simply unplug the LPG wire from the lamber and that clears the fault.

Just a thought.

bryan

hi bryan no i dont have lpg ....the guy from the garage has replaced the lambdas and it is still not right he says it is close but not quite there i have not spoke to him i talked to a mechanic who was working late on another car, he said there may be a blockage in the exhaust system, i am getting fed up with him now i estimate it is going to cost me 450.00 so far and it still has no mot i will be having words tommorow i am not buying a new exhaust too this is getting out of hand i think i am paying for his experiments regards dave
p.s my service history suggests that i had 2 sensors 24 months ago witch surely they last longer than that