Since i had my car set-up at MSD in June i've been suffering from a bad splutter/misfire. After thinking i'd solved it i haven't and i'm pissed off.

At MSD i had an EVO L1 chip for 803, T34, 500 also on that day i had a new rotor arm, CPS, Fuel regulator and -31

After the drive home 100 miles it inherited this misfire issue so i have since change 3 sets of 071 plugs gapped @ .65, dizzy cap, 909 motorsport leads, Grp A Coil, 3 bar map all brand new and after a small test drive the other day it ran fine.

After getting on the motorway yesterday it started again but is very intermittent for example it would splutter then stop if keeping steady revs but as soon as you change engine/rev speed it splutters. This is only off boost as whilst on boost it is like an absolute rocket and has no problems at all.

Due to changing everything on the ignition side i have starting to think is it a fuel problem??? so i've got a new fuel filter and some of that injector cleaner to try but if that doesn't cure it i am stumped. Most people i have spoken to have said it's strange i have spoken to Stu as well and he said check theirs no water on the pistons which their wasn't so not head gasket.

I would like to get it back down to MSD but i'm struggling to get time.

Any advice would be handy

 

Better of at MSD than fitting random bits to the car m8.

 

What condition is the loom in mate? it could be breaking down with age.

Also check the HT lead isn't close the the map sensor.

 

Had a similar problem on mine ages ago, replaced the CPS and the phase sensor and it cured the problem, i dont know which one was causing the problem because i replaced both at the same time and it ran fine afterwards. As you say you have already replaced the CPS it may be worth looking at the phase sensor? Also if i remember rightly there is a certain gap that must be maintained when fitting the CPS, maybe worth checking that?

 

From my MSD receipt

All sensors and ECU inputs have been checked and monitored with a pectel date logger and found to be operating correctly, including CPS, Phase, water, air temp, throttle, crank and map.

cps = 0.8mm
plugs = 0.65
phase regapped to correct distance

and the car covered about 120 miles after these chacks when the problem occured

Paul the coil lead is not near the map as Stu mentioned the same thing mate.

i know it would be better getting it back down there it's just time and a waiting list thats stopping me.

I'll try a phase sensor but what is that parts actual purpose??

 

The phase sensor tell sthe engines ecu what phase it is on what position the inlet cam is in, needed for sequential injection.
tabetha

 

Tab you have pm mate

 

had a similar problem a while ago changed the phase sensor and its been fine since

 

Just ordered a phase sensor we'll see if this sorts the problem.

 

I would say Phase sensor for sure.Make sure you fit the connector on the small loom onto the plug inside the dizzy round the right way . I fitted one to mine the other day and plugged it on the wrong way round and it wouldn,t start and kept kicking back LOL.

 

Got the phase sensor through, going to fit tomorrow but which bit needs gaping, can someone point it out.

Here is the picture of mine on the car




New phase - i take it Green = Red and Black = Blue

 

You need to fit the phase sensor and turn the engine untill one of the pointers is in line with the optical eye part of the sensor then adjust the gap between the two by moving the sensor untill you get 0.3mm gap using a feeler gauge. I,ve forgotten which way round the wires go on again but i can tell you that they sort of cross over between the sensor and the plug if that makes sense. I,ve been told its a lot easier to remove the dizzy to fit the new sensor but it can be done in situ if you have a lot of patience LOL .The screws will have become magnetic over time and can be a right pig to get back in the holes .

 

Looking again at your photos i would agree green = red. And its not an optical eye on the phase sesor its a pointer. Make sure you put the magnet supplied under the new phase sensor the right way round. You should have got a little bit of paper with the new one showing which way round it goes denoted by a white stripe. Hope that helps. Cheers Gaz

 

That sounds complicated mate the way you described, i need a haynes manual desperately

 

Honestly mate its not hard at all. It just sounds it the way I,ve described it

 

You see the lobe/pointing part of the shaft on the right hand side of the pic?

You have to turn the engine over until this is facing the phase sensor, and gap the gap between this and the phase sensor

I hope that is easier to understand

I think it'll cure your problems, it did ours

 

Right mate on the centre shaft, when thats pointing in the direction of the sensor between the two is the gap, i had no idea that was what needed doing, cheers.

Every days a school day

 

I had a cossie develop a missfire once and after spending ages trying to sort it we found one of the injector plugs wasnt sitting on quite right and with the heat of the engine was slightly lifting.

 

have you checked the tops of the plugs are screwed on tight?

 

ive fitted a phase sensor when the dizzy was on the car. I didnt think it was hard. I hope you get it sorted soon.

 

Yes mate they are tight

I did start to think is it fuel side so i've got a new filter, new o rings and a place down the road said they'll clean the injectors for Ł7 each.

But as for the phase i'll change that over the weekend when i get the gauges from work.

 

Yes its the gap between the two

Let us know if it fixes it

 

Will do James

 

Get on with it then

 

is it fixed then? Doesnt take that long to fit/gap a phase sensor and run it up the road

 

Changing on Monday as i'm at work until then

 

take the car back to Stu @ MSD and get him to fit a miracle kit, he sells it as the wasted spark set up. It is minimum requirement IMHO when owning a cosworth as the mis fires on my last cossie wont be missed

 

I would love to get that set-up but it costs ŁŁŁ's and then theirs the fitting Ł100+ and fuel to get there again so around Ł600+ maybe next year.

I managed to get the sensor in so i'll test the car again tomorrow on the motorway where this normally happens, i did remove all the plugs for inspection and did find that 2 were slightly lose after i had tightened them really well.

Oil/filter and fuel filter change on Tuesday so hopefully it will be running perfect for Sunday

 

Not got closed loop or wasted spark etc, runs perfect, only had to change phase sensor once in 4+years and thats all thats ever caused a misfire (once)

 

Right i am going out my mind with this, i can't find a set of feeler gauges that go low enough, i have 2 sets and all my mates are the same they only go down to .038mm is this fine for the gap or is this too large???

 

Think your getting a bit confused with the figures, you need 0.3mm not 0.03mm. Or otherwise if you've got a set of imperial feelers then it will be 0.012"

 

Right then mine is way out, no wonder the plugs are pretty black

Mine set at .038/.0015 and you saying it should be .305/.012 ???

Cheers for the help

Chris.

 

hope you get it sorted chris

 

If you're using metric (millimetres) feeler gauges the gap should be no smaller than 0.2mm and no bigger than 0.3mm so if you have a 0.25mm feeler gauge then use that as its the mid-limit.

If you're using imperial (inches) feeler gauges the gap should be no smaller than 0.008" and no bigger than 0.012" so use a 0.010" gauge as that is the mid-limit.

 

Cheers for the advice mate, i'll go and reset it now.

Chris.

 

Oi Chris,stop posting and get it reset m8

 

No problem mate.
As long as you know wether you're using metric or imperial gauges and double check the position of the decimal point is the same as in the figures i've given you then you should be ok.

 

Right the car still has a slight splutter every now and then, it's not perfect and everything has been change so back to the tuners it will be to find out the problem.

Cheers for all the help everyone, the car drives fine then a little splutter then fine.

 

Have you checked all the timing? Is it only on boost splutter or anywhere?

 

See you on Sunday then mate? We are off in the morning to start setting up at Donnington - brollies are loaded!!