AFM/MAF readings
Discussion
Have checked then cleaned and techecked my AFM 5AM.
It is a genuine landrover part.
Before cleaning Ignition on engone off it peaked at 2.4 and settled on 0.49 volts after 5 seconds
After cleaning 1.8 and 0.40 after 3 seconds.
So improved but still not good enough ?
If I need a replacement what is best to buy ?
It is a genuine landrover part.
Before cleaning Ignition on engone off it peaked at 2.4 and settled on 0.49 volts after 5 seconds
After cleaning 1.8 and 0.40 after 3 seconds.
So improved but still not good enough ?
If I need a replacement what is best to buy ?
Edited by blaze_away on Saturday 17th February 12:17
All you are looking at is the spike before the hot wire heats up, and the standby current with no airflow. These dont affect the values you get when the engine is running, so don't read to much into it. The voltage at idle is more important- heres what a 4 ltr engine looks like at start up.
Interesting thank you, at idle I am getting 1.88 volts 4.6 litre at 900 rpm
Is that a bit high.
Main reason for all this checking is I am trying find root cause of high fuel consumption.
Have checked and replaced all ignition system new stepper motor. New ecu chip with one of Steve Sprints bin files
I get lovely stable idle no shunting good acceleration. But still just 14mpg !!!
I have bought a fuel pressure test rig will check that next. I am running out of ideas.
Is that a bit high.
Main reason for all this checking is I am trying find root cause of high fuel consumption.
Have checked and replaced all ignition system new stepper motor. New ecu chip with one of Steve Sprints bin files
I get lovely stable idle no shunting good acceleration. But still just 14mpg !!!
I have bought a fuel pressure test rig will check that next. I am running out of ideas.
Not a million miles out- especially if the idle is 900 rpm- the general figures for AFM voltage are a based on a lower idle. At this point Ill do a Chimp on Gas, and say go and check the basics- what are all the plug colours, Id say at 14 mpg they will be black if its over fueling, or spotlessly clean you have a cylinder not firing.
Yeah hear what you are saying and I have done that a couple of weeks back.
Pulled the set of B7s and they all looked the brown tips and black collars. Put new 6s in got rid of the extenders and fitted socks. New ecu chip. new coil, new amp new cap leads and rotor arm. Fired up and run for 5 seconds quickly felt all the individual headers and every one of them hot to touch. 14 mpg before all this snd still 14mpg after it.
I need a fitting for pressure kit as nothing fits the schrader on the rail. Will try to get that asap then check fuel pressure and recheck the plugs.
Anyone know where to get adaptors for std tyre type schrader valve ?
Pulled the set of B7s and they all looked the brown tips and black collars. Put new 6s in got rid of the extenders and fitted socks. New ecu chip. new coil, new amp new cap leads and rotor arm. Fired up and run for 5 seconds quickly felt all the individual headers and every one of them hot to touch. 14 mpg before all this snd still 14mpg after it.
I need a fitting for pressure kit as nothing fits the schrader on the rail. Will try to get that asap then check fuel pressure and recheck the plugs.
Anyone know where to get adaptors for std tyre type schrader valve ?
I have been there, car running very well on the non cat map but ridiculous mpg (15), even when when really trying to drive as gently as possible.
I am in the process of going through all the ignition components as well, and also the vacuum seals, especially the plenum and stepper. Afm checking and spark plugs also on the list as my heat socked ht leads came up looking like new this morning when I took them all out to check them.
The thread about the vacuum advance going directly to the plenum is interesting and I am willing to try that too. A suck test on the vacuum pipe to the dizzy made the clicking sound so hopefully the dizzy is also working properly but I will get get a strobe light on a rechecked tdc mark on there too, just in case the timing was not set right in the past.
I am in the process of going through all the ignition components as well, and also the vacuum seals, especially the plenum and stepper. Afm checking and spark plugs also on the list as my heat socked ht leads came up looking like new this morning when I took them all out to check them.
The thread about the vacuum advance going directly to the plenum is interesting and I am willing to try that too. A suck test on the vacuum pipe to the dizzy made the clicking sound so hopefully the dizzy is also working properly but I will get get a strobe light on a rechecked tdc mark on there too, just in case the timing was not set right in the past.
Following up on this I have checked fuel pressure at the injector rail
Ignition on pump running 38 psi
Ignition still on pump stopped 36 psi
Ignition on engine running 31 psi
I these are ok ?
Went for a hard drive and cut the engine at high revs (to preserve plug condition)
Pulled all the plugs and all are sooty ends light brown tips.
Plug 2 7 8 look a little darker brown on one side.
I think this points to injectors needing a service, what do you guys think ?
Ignition on pump running 38 psi
Ignition still on pump stopped 36 psi
Ignition on engine running 31 psi
I these are ok ?
Went for a hard drive and cut the engine at high revs (to preserve plug condition)
Pulled all the plugs and all are sooty ends light brown tips.
Plug 2 7 8 look a little darker brown on one side.
I think this points to injectors needing a service, what do you guys think ?
An odd symptom you get with fouled injectors is uneven plug insulator colour- Im told this is due to the fuel not atomising correctly, so as it enters the combustion chamber, it effectively washes one side of the plug, so its remains white on one side, and tan on the other. I did scoff at this idea somewhat when I heard it considering the amount of swirl that goes on in the inlet, but I did get even plug colour post an injector clean, so it may have had some truth in it. A pure white plug can also be a non firing cylinder. Your plugs really dont look that bad on the whole and I dont think injectors are to blame for the poor MPG. Mind you a couple of bottle of injector cleaner should work well enough if it worries you. Is the car down on power to notice? Over rich mixtures at low speed make the car fell flat, and then as the RPM rises and the mixture corrects the power comes in with a real woosh
Power is all good engine revs well idles well and goes like stink. eg on 1/4 mile drag strip it keeps pace well with classichim's sweet car (he is similar spec 4.6 with mbe and gets good economy) his 12.6 vs my 12.9
I too am sceptical that its injectors but running out of ideas so I will either get an overhaul or fit new then see how things are.
I too am sceptical that its injectors but running out of ideas so I will either get an overhaul or fit new then see how things are.
Proper fast car to keep up with mine
Or there both slow
Injector cleaner tidied up my idle a bit and silenced the injector tapping I was hearing every now and then.
I’ve also suffered from the regulator sort of vibrating and giving a whine for a second or so on start up. Defo a bit dry so I use the injector cleaner regularly now and it runs lovely and silent.
It’s honestly made a big difference from a noise point of view, I’d be constantly trying to decide what followers just tapped, turns out it was injectors clattering away all along because adding injector cleaner it’s also a form of lube I thought, silenced them. Result
Plugs look pretty good too I’d say, is it an optical illusion or has No 6 plug got a small gap. 0.7 mm is good on CUX.
Have you got some porting going on there Frank?
It’s bloody fast alright
Have you checked the timing.
Or there both slow
Injector cleaner tidied up my idle a bit and silenced the injector tapping I was hearing every now and then.
I’ve also suffered from the regulator sort of vibrating and giving a whine for a second or so on start up. Defo a bit dry so I use the injector cleaner regularly now and it runs lovely and silent.
It’s honestly made a big difference from a noise point of view, I’d be constantly trying to decide what followers just tapped, turns out it was injectors clattering away all along because adding injector cleaner it’s also a form of lube I thought, silenced them. Result
Plugs look pretty good too I’d say, is it an optical illusion or has No 6 plug got a small gap. 0.7 mm is good on CUX.
Have you got some porting going on there Frank?
It’s bloody fast alright
Have you checked the timing.
Id stick it on a rolling road for a full gas analysts then- if there is a genuine fault one of the gas results will be wrong. If the fuel is not producing power and not being burnt the HC count will be high, and like wise a wrong mixture will show up as bad CO2 or high Nox. Ignition timing is straight forward enough with strobe- other wise your brakes are binding!
blitzracing said:
Id stick it on a rolling road for a full gas analysts then- if there is a genuine fault one of the gas results will be wrong. If the fuel is not producing power and not being burnt the HC count will be high, and like wise a wrong mixture will show up as bad CO2 or high Nox. Ignition timing is straight forward enough with strobe- other wise your brakes are binding!
I am taking it to Dynodaze Nuneaton end next week to see what the numbers look like.Gassing Station | Chimaera | Top of Page | What's New | My Stuff