So far have done the following

4x coilpacks (from Ford)

New NGK Tr6 AP 13 (previous owner) maybe fake?

New o2 sensor intermotor

Emission test carried out 0.00 CO and 5PPM HC lambda 1.0 at fast idle. CO at natural idle 0.00

I still have misfire data being logged in mode6. Using Tesco 99 Ron and a single dose of injector cleaner. Anyone had any luck with the cheap injectors that you can get? Mode6 is reporting as per the attached.

Is it move injectors around to see if fault follows is that an easy task on these or should I get some replacement orings first

 

The injectors are just clipped onto the rail so easy to swap around.  Just pull the rail and unclip them.  Though at this age I wouldn't be surprised if an o-ring splits when removed.  Personally I'd have some spares to hand before removing the rail if the car is used daily.

Thanks. Just to confirm that the parts cannon was pulled for the coils and it was a good call as the misfire you could feel from cold start has gone. Any feelings on the cheap injectors?

22 minutes ago, scoobydo123 said:

Thanks. Just to confirm that the parts cannon was pulled for the coils and it was a good call as the misfire you could feel from cold start has gone. Any feelings on the cheap injectors?

Never used cheap injectors myself.  I'd probably prefer a good used set, ideally low mileage, instead of aftermarket, but that's just my own preference.

Maybe I should get what I have cleaned, obviously means some downtime though. Car has only done 91,000. When I took the pipe off the throttle body it was quite black and sticky in there.

IDI petrol injector cleaning should be pretty quick.  Just chuck them in an ultrasonic cleaner for 10 minutes.

I wouldn't really expect them to be dirty though, petrol is a strong solvent after all, it'll strip any oil or grease from the parts it touches.

I took a reading of mode6 data after switching off and restarting. No revving or anything and car probably ran for 10 seconds max. This generated 158. Cannot feel the misfire. Reluctant to just leave it though. Only other things I get occasionally is a ucode in the ABS. Cannot remember the code but it mentions loss of comms between modules. I do remember reading some where that the logic behind misfires uses the ABS sensors to track rough terrain not sure how it can do that. Maybe these are phantom misfires. Will need to get all the misfire PIDs up and see what they look like. Got any clues your end? Tks

I haven't heard of the ABS sensors being used to detect a misfire.  Usually it's detected by crank sensor variations which is how it can precisely tell which cylinder has misfired.  It can also use pre-cat lambda readings although they're slightly less reliable.

10 seconds of running at 800rpm would only be about 60 'fires' on one cylinder (with fuel, not including wasted sparks) so I don't see how it can possibly have so many misfires in such a short time.  That does make it seem like it's being calculated or estimated using something else.  Very odd that it's only one cylinder as well.  I must admit, this isn't something I would have looked into unless I could feel a misfire or was getting a fault code for it, so I'm not sure what the 'normal' rate would be.

 

If it was losing comms between ABS module and cluster then that's one of the common signs for cluster solder failing.  If it was losing comms between PCM and ABS module then that would point more towards the ABS module or a wiring fault.  The ABS module is used by the PCM for a road speed input so it can affect engine running on the move if that input is lost.

I'd be tempted to change the plugs again for known genuine

Add an additional earth strap from the cylinder head to the body

@TomsFocus here is the reference material of Ford OBD protocol in relation to use of the ABS.

The Misfire Monitor includes a Rough Road Detection (RRD) system to eliminate false misfire indications due to 
rough road conditions. The RRD system uses data from ABS wheel speed sensors for estimating the severity of 
rough road conditions. This is a more direct measurement of rough road over other methods which are based on 
driveline feedback via crankshaft velocity measurements. It improves accuracy over these other methods since it 
eliminates interactions with actual misfire. 
In the event of an RRD system failure, the RRD output will be ignored and the Misfire Monitor will remain active. 
An RRD system failure could be caused by a failure in any of the input signals to the algorithm. This includes the 
ABS wheel speed sensors, Brake Pedal sensor, or CAN bus hardware failures. Specific DTCs will indicate the 
source of these component failures. 
A redundant check is also performed on the RRD system to verify it is not stuck high due to other unforeseen 
causes. If the RRD system indicates rough road during low vehicle speed conditions where it is not expected, the 
RRD output will be ignored and the Misfire Monitor will remain active. 

OK so have a theory that maybe beyond the misfire that I could feel from cold that is now not apparent maybe the misfires were still there just being masked due to the criteria of full detection not being met such as fuel level and coolant temp etc. Here is some more reference material.

"Profile correction" software is used to "learn" and correct for mechanical inaccuracies in the crankshaft position 
wheel tooth spacing. Since the sum of all the angles between crankshaft teeth must equal 360o, a correction factor 
can be calculated for each misfire sample interval that makes all the angles between individual teeth equal. . The 
LDR misfire system will learn one profile correction factor per cylinder (ex. 4 correction factors for a 4 cylinder 
engine), while the HDR system will learn 36 or 40 correction factors depending on the number of crankshaft wheel 
teeth (ex. 36 for V6/V8 engines, 40 for V10 engines). 
The corrections are calculated from several engine cycles of misfire sample interval data. The "mature" correction 
factors are the average of a selected number of samples. In order to assure the accuracy of these corrections, a 
tolerance is placed on the incoming values such that an individual correction factor must be repeatable within the 
tolerance during learning. This is to reduce the possibility of learning corrections on rough road conditions which 
could limit misfire detection capability and to help isolate misfire diagnoses from other crankshaft velocity 
disturbances. 
To prevent any fueling or combustion differences from affecting the correction factors, learning is done during 
decel-fuel cutout. This can be done during closed-throttle, non-braking, de-fueled decelerations in the 60 to 40 mph 
range after exceeding 60 mph (likely to correspond to a freeway exit condition). In order to minimize the learning 
time for the correction factors, a more aggressive decel-fuel cutout strategy may be employed when the conditions 
for learning are present and are typically learned in a single 60 to 40 MPH deceleration, but can be learned during 
up to 3 such decelerations, or over a higher number of shorter duration decelerations.. 
For Hybrid Electric Vehicles profile is learned by using the electric drive to spin the crankshaft on the first engine 
shutdown during which time profile is calculated. 
Since inaccuracies in the wheel tooth spacing can produce a false indication of misfire, the misfire monitor is not 
active until the corrections are learned. In the event of battery disconnection or loss of Keep Alive Memory the 
correction factors are lost and must be relearned. If the software is unable to learn a profile after three 60 to 40 
mph decels, a P0315 DTC is set. 
Neutral Profile Correction and Non-Volatile Memory 
Neutral profile learning is used at End of Line to learn profile correction via a series of one or more neutral engine 
rpm throttle snaps. This allows the Misfire Monitor to be activated at the Assembly Plant. A Test Tool command is 
required to enable this method of learning, so this method will only be performed by a Plant or Service technician. 
Learning profile correction factors at high-speed (3,000 rpm) neutral conditions versus during 60-40 mph decels 
optimizes correction factors for higher rpms where they are most needed and eliminates driveline/transmission and 
road noise effects. This improves signal to noise characteristics which means improved detection capability. 
The profile correction factors learned at the Assembly Plant are stored into non-volatile memory. This eliminates 
the need for specific customer drive cycles. However, misfire profiles may need to be relearned in the Service Bay 
using a service procedure if major engine work is done or the PCM is replaced. (Re-learning is not required for a 
reflash.) 
The 60-40 mph decel profile learning algorithm has been left active in the software as a backup

Misfire Monitor Operation: 
DTCs P0300 to P0310 (general and specific cylinder misfire) 
P1336 (noisy crank sensor, no cam/crank synchronization) 
P0315 (unable to learn profile) 
P0316 (misfire during first 1,000 revs after start-up) 
Monitor execution Continuous, misfire rate calculated every 200 or 1000 revs 
Monitor Sequence None 
Sensors OK CKP, CMP, MAF, ECT/CHT 
Monitoring Duration Entire driving cycle (see disablement conditions below) 
Typical misfire monitor entry conditions: 
Entry condition Minimum Maximum 
Time since engine start-up 0 seconds 0 seconds 
Engine Coolant Temperature 20 oF 250 oF 
RPM Range (Full-Range Misfire certified, with 2 rev
delay) 
2 revs after exceeding 
150 rpm below “drive” 
idle rpm 
redline on tach or fuel 
cutoff 
Profile correction factors learned in KAM Yes 
Fuel tank level 15% 
Typical misfire temporary disablement conditions: 
Temporary disablement conditions: 
Closed throttle decel (negative torque, engine being driven) 
Fuel shut-off due to vehicle-speed limiting or engine-rpm limiting mode 
High rate of change of torque (heavy throttle tip-in or tip out) 
Rough Road conditions present 
Typical misfire monitor malfunction thresholds: 
Type A (catalyst damaging misfire rate): misfire rate is an rpm/load table ranging from 40% at idle to 4% at 
high rpm and loads 
Type B (emission threshold rate): 1% to 2% 

Correction Operation

DTCs P0315 - unable to learn profile in three 60 to 40 mph decels

Monitor Execution Once per profile learning sequence.

Monitor Sequence: Profile must be learned before misfire monitor is active.

Sensors OK: CKP, CMP, CKP/CMP in synch

Monitoring Duration; 10 cumulative seconds in conditions

(a maximum of three 60-40 mph defueled decels)

Typical profile learning entry conditions (Customer drive cycle):

Entry condition Minimum Maximum

Engine in decel-fuel cutout mode for 4 engine cycles

Brakes applied (Brake On/Off Switch) No No

Engine RPM 1300 rpm 3700 rpm

Change in RPM 600 rpm/background

loop

Vehicle Speed 30 mph 75 mph

Learning tolerance 1%

Typical profile learning entry conditions (Assembly Plant or Service Bay):

Entry condition Minimum Maximum

Engine in decel-fuel cutout mode for 4 engine cycles

Park/Neutral gear

Engine RPM 2000 rpm 3000 rpm

Learning tolerance 1% 

Sorry about the formatting of the last 2 messages. Here are the screenshot that is easier on the eye.

 

 

 

12 hours ago, TomsFocus said:

I haven't heard of the ABS sensors being used to detect a misfire.

You are correct Tom, the detection comes from the Crankshaft Sensor. If the ABS Sensors did detect road conditions rough enough to give false Misfire Detection then the PCM would ignore the false information from the rough road.

If the ABS sensors were not doing their job properly then the PCM would ignore their input when calculation Misfires and would no doubt flag up a Fault Code for the ABS System.

Sorry I was  referencing that ABS forms part of the logic for misfire detection not as the actual direct input for detecting the misfire. As I understand it in a simplistic view  that the calculation starts when the piston should be accelerating away from TDC if the crank does not meet a degree in the time expected according to the preprogrammed and learned values from coast down then a count will be logged. Havent got my head around what is happening in my case why there are illogical events however what I have learnt is that perhaps when I thought we were clear that either drive cycles had not been completed or lack of fuel or something else maybe hadn't passed so just hadn't activated the required check points. So far haven't seen the individual cylinder count go above 0.249 however concern is with the misfire count being in the 20k plus. Is there much likelyhood of it being the injectors given that emission test was quite good however thinking about it the duty cycle on a basic emission test is nowhere near where it is when engine under load.

@DaveT70 thanks for the idea of the earth strap will give that a go. Certainly things have improved since changing ign coils but still not quite there but so far nothing that can be felt when driving which wasn't the case until the ign coils were changed. Deffo bit of a challenge this one. Doesn't help that it is my Sons daily and he works long hours so getting access is a challenge.