advice about engine emissions 2.8i please...
Discussion
Hi - I am new to this but i hope there is someone who may have some ideas. My 280i failed its emissions test in a MOT. I have changed air and fuel filters; HT leads, spark pugs, dizzy cap, rotor arm; and checked the timing.
My Tasmin seems to have a slight miss-fire (noticeable at low revs) and the CO reading from the left bank of cylinders (3.6) is double that of the right (1.8). The right bank is well over the maximum allowed for hydro-carbons.
The garage suggested it was likely to be an electrical fault but all the cylinders do seem to be firing and replacing leads etc hasn't helped.
Anyone got any words of wisdom out there?
Advice would be greatly appreciated since I was planning to go to the TVR open day near Brighton at the weekend and maybe also catch some racing.
Cheers. Nads
My Tasmin seems to have a slight miss-fire (noticeable at low revs) and the CO reading from the left bank of cylinders (3.6) is double that of the right (1.8). The right bank is well over the maximum allowed for hydro-carbons.
The garage suggested it was likely to be an electrical fault but all the cylinders do seem to be firing and replacing leads etc hasn't helped.
Anyone got any words of wisdom out there?
Advice would be greatly appreciated since I was planning to go to the TVR open day near Brighton at the weekend and maybe also catch some racing.
Cheers. Nads
If you pop out the injectors your can should see the build up of durt arround the pin hole, have you thouth about using those fuel additives that should clean injectors. there is places that can sonic clean these, try asking the garage owner if he knows of any place or any good car tuner too
Campbell
Campbell
Your slight miss will knock up the hydrocarbons, so cure the fault and you should get through the test ok.
Pull off one plug lead at at time (till you don't get an extra miss) to find the bad cylinder.
Remoove plenum, option one remove the possible offending injector, soak overnight in Berrymans B12 or UK equivalent. put back, try again
Option 2 remove all injectors, get them checked, any decent mech should be able to do it or at least tell you where he sends his! Just tell him opening pressure is 3.2 - 4.0 Bar. (you don't need ultra sonic cleaning till you prove it's a bad spray pattern or dribbling)
I personally would swap the plug and lead on the bad cylinder before I pulled off the plenum! even though they are new.
Good luck
Jeff
Pull off one plug lead at at time (till you don't get an extra miss) to find the bad cylinder.
Remoove plenum, option one remove the possible offending injector, soak overnight in Berrymans B12 or UK equivalent. put back, try again
Option 2 remove all injectors, get them checked, any decent mech should be able to do it or at least tell you where he sends his! Just tell him opening pressure is 3.2 - 4.0 Bar. (you don't need ultra sonic cleaning till you prove it's a bad spray pattern or dribbling)
I personally would swap the plug and lead on the bad cylinder before I pulled off the plenum! even though they are new.
Good luck
Jeff
Thanks for your help.
Still not having much luck - leads and plug swap hasn't changed anything. The garages I have contacted have given me numbers of specialists they use however none of them do 'carbon flow' or 'sonic cleaning' anymore.
Most of them lost interest when I told them how old the car was and said they usually just replace parts without trying to test or fix them! I guess it's the 'throw-away world' we live in!
The last one said he thought it was unlikely to be injectors and said he would look at air leaks and tappets first. Is he pulling my leg or does this make sense? Excuse my lack of knowledge but I am not even sure where I should be looking for air leaks. Any ideas?
Thanks to those who have replied.
I am off to pull out some injectors now!
Still not having much luck - leads and plug swap hasn't changed anything. The garages I have contacted have given me numbers of specialists they use however none of them do 'carbon flow' or 'sonic cleaning' anymore.
Most of them lost interest when I told them how old the car was and said they usually just replace parts without trying to test or fix them! I guess it's the 'throw-away world' we live in!
The last one said he thought it was unlikely to be injectors and said he would look at air leaks and tappets first. Is he pulling my leg or does this make sense? Excuse my lack of knowledge but I am not even sure where I should be looking for air leaks. Any ideas?
Thanks to those who have replied.
I am off to pull out some injectors now!
It could possibly be an airleak, any air pulled in after the airflow meter will result in a lean mixture / misfire, the easist way to find them is to run the engine and spray lighter gas around all the joints post meter if the engine rev's up you've found your leak.
Tappet clearances are a mabye, if one is too tight then it'll allow gas past the seat and cause rough running.
Matt
Tappet clearances are a mabye, if one is too tight then it'll allow gas past the seat and cause rough running.
Matt
There seems to be a lot of advice here. I've got more help through PH than the professionals. (No remarks about 3 litre capris please.)
Thanks Wedg1e, Campbell, Jeff and Matt.
I'll have a go at the next bit.
I spoke too soon when I said I would get the injectors out. One came out without problems but the others are in danger of rolling the o-rings off the ends as I am trying to get them out (because the collar-type caps at the top aren't moving and won't come up with the injectors) if you see what I mean.
I am starting to see why so many garages aren't sympathetic towards older cars!
>> Edited by nads on Tuesday 17th August 00:52
Thanks Wedg1e, Campbell, Jeff and Matt.
I'll have a go at the next bit.
I spoke too soon when I said I would get the injectors out. One came out without problems but the others are in danger of rolling the o-rings off the ends as I am trying to get them out (because the collar-type caps at the top aren't moving and won't come up with the injectors) if you see what I mean.
I am starting to see why so many garages aren't sympathetic towards older cars!
>> Edited by nads on Tuesday 17th August 00:52
An air leak on CIS will normally F'up all cylinders equally, (depends where the leak is) but as you have high hydros on one side only I think you were on the right track before speaking to the mech who may not have known your car was CIS. Although while you have the plenum off you could check for a tight valve, no guage needed, just make sure there is some play when valve is closed.
Look for a small independent Porsche guy he will be able to check opening and pattern.
Look for a small independent Porsche guy he will be able to check opening and pattern.
Thanks 'Sevans'
As it turned out, I managed to get a replacement for an injector that looked dodgy. I also looked at the tappets and (as you say) a few of them were a bit tight. (No play at all on some - let alone 0.35 or 0.4)
Put the car back together at night by the light of a table-lamp in order to get a retest before the garage bloke went on holiday! (What we do for TVRs.)
As soon as I started it I thought I had done something wrong as it straight away went to an idle of over 2000!
Quickly adjusted the idle (while annoying the neighbours)and it ran really well.
Funny thing is the other bank now gives a slightly higher CO reading! (Well, with less than 0.5% difference I'm happy.)
Thanks to Matt, Wedg1e, Campbell, Jeff and Sevan.
Car now running great at the moment.
Yes - it passed!
This is the first time I have looked at PH and I have been impressed with the expertise and how friendly people are (to complete strangers). Thanks.
By the way (excuse my lack of knowledge) but what does CIS stand for?)
Cheers
Nadeem
>> Edited by nads on Wednesday 18th August 14:43
As it turned out, I managed to get a replacement for an injector that looked dodgy. I also looked at the tappets and (as you say) a few of them were a bit tight. (No play at all on some - let alone 0.35 or 0.4)
Put the car back together at night by the light of a table-lamp in order to get a retest before the garage bloke went on holiday! (What we do for TVRs.)
As soon as I started it I thought I had done something wrong as it straight away went to an idle of over 2000!
Quickly adjusted the idle (while annoying the neighbours)and it ran really well.
Funny thing is the other bank now gives a slightly higher CO reading! (Well, with less than 0.5% difference I'm happy.)
Thanks to Matt, Wedg1e, Campbell, Jeff and Sevan.
Car now running great at the moment.
Yes - it passed!
This is the first time I have looked at PH and I have been impressed with the expertise and how friendly people are (to complete strangers). Thanks.
By the way (excuse my lack of knowledge) but what does CIS stand for?)
Cheers
Nadeem
>> Edited by nads on Wednesday 18th August 14:43
Luckily it was a shedload of time rather than money! Are any of you going to the Dream Machines open day on Saturday? I don't know which region you are in but Dream Machines are in E Sussex. It would be nice to say hello and put a face to the typeface. My car is a black 2+2 Taz (previously owned by a known PH person I believe. There's a sticker in the window for PistonFest 03!)
Cheers Nads
Cheers Nads
Dave
Great powers of deduction! I suspect that your PH name gives me a clue how you know.
Yes is was Richard's (TVRCC N Yorkshire's RO) car. I may be new to PH but it sounds like the car isn't! Maybe some of you know more about the history of my car than I do.
After a little research I think Rich's name is 'Gemini' on this site. Did he ever get to buy the Grif he wanted in the end?
Great powers of deduction! I suspect that your PH name gives me a clue how you know.
Yes is was Richard's (TVRCC N Yorkshire's RO) car. I may be new to PH but it sounds like the car isn't! Maybe some of you know more about the history of my car than I do.
After a little research I think Rich's name is 'Gemini' on this site. Did he ever get to buy the Grif he wanted in the end?
and welcome to what is affectionately known as the mad-house.. you've got a rare and well cared for wedge there.. top choice.. btw - I believe 'Gemini' went for a 4.0 Chimaera in the end.. nads said:
Dave
Great powers of deduction! I suspect that your PH name gives me a clue how you know.
Yes is was Richard's (TVRCC N Yorkshire's RO) car. I may be new to PH but it sounds like the car isn't! Maybe some of you know more about the history of my car than I do.
After a little research I think Rich's name is 'Gemini' on this site. Did he ever get to buy the Grif he wanted in the end?
Ah, thought it might be. I never actually saw the car itself, other than in pictures. Yes, Rich is Gemini and still about, though now in the Chimaera section more often I suspect, having bought a bargain one of them it seems. Haven't seen it as he insisted on taking the Skoda to last meeting.
Can I have your cars picture? In a geeky kind of way I was intending to gather up a list of the 2+2 and pictures on my website, hmmm, don't seem to have many yet!
cheers
Dave
Well Nads
It feels spooky you turning up like this
Dave (Yorkie) let me know you were here.
I was just tellinh him at our last meeting how good it was to see a 2+2 on the road and I went all gooey for the old girl.
Glad you have her running well again. I do miss her in a funny way.
I bought a pearl green Chimaera in the end but do hanker for something a little more monsterous! (see profile photo)
Would be great to see you and the car again - going to Cardiff?
Ive stacks of photos Dave!
Nads car now though so if its ok Ill release?
It feels spooky you turning up like this
Dave (Yorkie) let me know you were here.
I was just tellinh him at our last meeting how good it was to see a 2+2 on the road and I went all gooey for the old girl.
Glad you have her running well again. I do miss her in a funny way.
I bought a pearl green Chimaera in the end but do hanker for something a little more monsterous! (see profile photo)
Would be great to see you and the car again - going to Cardiff?
Ive stacks of photos Dave!
Nads car now though so if its ok Ill release?
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