How to increase the fuel amount to the mix in a Griff 500?
Discussion
Hi, I've sent my Griffith 500 to make a full check of the electrics, everything is ok.
The Griffith has a few malfunctions, maybe you've red my previous (desperate) threads, the worst of all are that the engine does not rev happily above 3.500/4.000 RPM and it pops strongly when you leave the right foot alone...
My garaje buddy says the CO2 reads below 1 and it should be above that figure hence on his opinión the engine lacks fuel, the mix is too lean and that he doesn't know how to increase the fuel rate into the mix because he hasn't any spec of my CUX box, I told him that it would be enough to change the chip for another one with a higher rate of fuel delivery (I have a tornado mapped by Mark Adams in my CUX box)...He said that that is not the way...
It's 18 years I have this very same Griffith, I've always thought that changing the chip would regulate the fuel supply...!!!
The Griffith has a few malfunctions, maybe you've red my previous (desperate) threads, the worst of all are that the engine does not rev happily above 3.500/4.000 RPM and it pops strongly when you leave the right foot alone...
My garaje buddy says the CO2 reads below 1 and it should be above that figure hence on his opinión the engine lacks fuel, the mix is too lean and that he doesn't know how to increase the fuel rate into the mix because he hasn't any spec of my CUX box, I told him that it would be enough to change the chip for another one with a higher rate of fuel delivery (I have a tornado mapped by Mark Adams in my CUX box)...He said that that is not the way...
It's 18 years I have this very same Griffith, I've always thought that changing the chip would regulate the fuel supply...!!!
FlipFlopGriff said:
Suggest you get it set up (idle, AFM, Throttle pot, timing etc) and if not mapped then it probably needs to be. Any issues you then have can be tackled.
What was it like before the chip?
FFG
The chip was tuned by Mark Adams to complement other mods: decatted sport exchaust, larger AM, triple carbón Intake...What was it like before the chip?
FFG
PeteGriff said:
Don't PANIC panic. Put your original 500 chip back in, should be an easy enough job (I have changed chips several times now whilst trialling different maps). Have you done any other mods other than the tornado chip? If not take it out and place the original back in. StevSprint and Blitzracing on here should be able to offer some guidance. If it was a precat I could have given you AFM trim voltages to set up CO/fuel air ratio, but yours has the lamda sensors which should detect and cause adjustment via the ECU of CO trim. Hope that is of help? Regards, Pete
The mods as I said in my previous post were decat exhaust, triple ACT carbón intake, larger AM...the chip was tuned to match these mods.There is no lambda sensor anymore, I've made a connect to bypass them...
So the questions is, could I adjust the mix fuel/air through the chipping?
Challenger C4s said:
Just a suggestion, but have you checked the fuel pressure. a drop in pressure would greatly affect higher rpm rather than tick over. Have you had the fuel filter changed recently.
Good luck with it.
I've taken back the Griffith from the garage with the same probs, they said the electric system is ok (well, and that alone is a great step forward...), on my opinion the garage guy is right, there isn't enough fuel getting to the engine, it does barely gets to 4K rpm but at idle and up to about 3K rpm it goes like on silk, the engine pops like mad at higher revs, even standing with neutral gear pressing the right pedal up to 4/5K rpms it pops plenty and...if you keep going as fast as possible in any gear the car just dies...leave it alone 5 secs and it'll restart.Good luck with it.
Fuel filter in the tank was cleaned a few years ago, I remember having problems then, it was cleaned and all the gremlins disappeared, the filter near the fuel pump is clean.
I'll order a new tornado chip from Mark Adams, do you think a chip can fall in disgrace after a few years, getting old and cracked?
Maybe the best solution would be to place a nice carb on he engine and say bye bye to the whole electronic s
t...Fuel pressure is ok, around 3/3.20...
Edited by panic on Friday 24th October 20:27
blitzracing said:
You have a lot of unknowns here- the first is the fuel pressure- you need to measure this with the engine under full load when the demand on the pump is at its highest. You cant rely on measurement at tick over, as this wont show up if the fuel supply is restricted under load. The symptoms you describe sound like pump delivery or restricted fuel supply if its that bad. One question though- is this a new set up that does not work, or has it been running OK, and now gone wrong? It it has worked in the past you cant blame the fuel map chip.
The things that have a major affect the mixture are:
Fuel pressure.
AFM output voltage
Fuel map
Injector peak flow rate.
As Steve Sprint says you cant simply by pass the lambda probes, they are critical to get the map correct. Even if you switch to the non catalysts fuel map to by pass the Lambda probes, do you even know if the non catalyst fuel map is correct for your engine set up? It could be bog standard LandRover- you would need to check this with Mark Adams.
Thanks for your comments, here are a few answers:The things that have a major affect the mixture are:
Fuel pressure.
AFM output voltage
Fuel map
Injector peak flow rate.
As Steve Sprint says you cant simply by pass the lambda probes, they are critical to get the map correct. Even if you switch to the non catalysts fuel map to by pass the Lambda probes, do you even know if the non catalyst fuel map is correct for your engine set up? It could be bog standard LandRover- you would need to check this with Mark Adams.
1) Yes, the set up has been working well for some time, the fuel map chip has been originally tuned by Mark Adams for this specific set up.
2) AFM, the black plastic 20AM Bosch has already given me problems a few years ago, the one I have is the second I change, it could be this the origin of all these malfunctions?
3) Fuel pressure, the garage buddy told me the pressure is enough but I have to ask if he tested the pressure at high load or only at idle...
Could it be the tank fuel filter that might be obstructed?
Thanks.
spitfire4v8 said:
the 20am is a lucas / sagem unit not bosch .. theyre cheap secondhand if you want to buy one for a test. The bosch AFM isn't the same but you could maybe still buy a used one cheap as a test?
Has the fuel pressure been measured under load when the prolem is there? Sounds like a fuel starvation issue under load from some of your description
Yes, you're right, sorry.Has the fuel pressure been measured under load when the prolem is there? Sounds like a fuel starvation issue under load from some of your description
Here are two pics of my AFM..
Where could I buy new this same Lucas hardware?
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