scott02464
Active Member
Yes mate still very slight misfire but it's mainly for bad idle and spluttering when engine is cold, something isn't switching correctly, as if the 'choke isn't on' effect. If that makes sense?
Yes mate still very slight misfire but it's mainly for bad idle and spluttering when engine is cold, something isn't switching correctly, as if the 'choke isn't on' effect. If that makes sense?
eightinavee
Well-Known Member
Bit pi--ed now,I'll try to help in the mornin.
scott02464
Active Member
PromnightDumpsterbaby
New Member
gotta be rich to run it nowadays
scott02464
Active Member
It's when I start up from cold (runs and idles fine when warm)
When I select drive the revs drop straight down to nearly stall, when I go to accelerate there's no power at all for about 4 seconds then picks straight up and goes? This carrys on until it has warmed up
I put the voltmeter on the battery this morning and it read 12.0 volts.
I then started the engine and then got 14.65 volts.
Would a weak battery cause my symptoms? Just a thought??
eightinavee
Well-Known Member
Ok,couple of things;
The sensors are 5-0v, NOT 0-5v - This means their natural output is 5v,so when they switch they go down to 0v.(Unlike the Zirconia sensors on a Thor engine which have a natural output state of 0v and switch up to 0.8v to give a rich signal.)
Forget the battery,if its low on voltage when starting you'll soon get "gearbox Fault" etc coming up on the message display whilst cranking.
"A slight misfire" is TOO much - it must not misfire AT ALL or the fuel trims will go negative and the remaining cylinders that are firing properly will end up with a very lean mixture and with a cold engine it will not make progress - then stall. ( I think this is where most of your problems lie.)
What does the air flow meter read at idle with the engine hot all loads off,in park/neutral ? Should be 22-25KG/Hr And is it a genuine sensor ? I also dont like the idea of cleaning them,I'd rather let the Gems ecu adapt with the sensor slowly degrading.
The sensors are 5-0v, NOT 0-5v - This means their natural output is 5v,so when they switch they go down to 0v.(Unlike the Zirconia sensors on a Thor engine which have a natural output state of 0v and switch up to 0.8v to give a rich signal.)
Forget the battery,if its low on voltage when starting you'll soon get "gearbox Fault" etc coming up on the message display whilst cranking.
"A slight misfire" is TOO much - it must not misfire AT ALL or the fuel trims will go negative and the remaining cylinders that are firing properly will end up with a very lean mixture and with a cold engine it will not make progress - then stall. ( I think this is where most of your problems lie.)
What does the air flow meter read at idle with the engine hot all loads off,in park/neutral ? Should be 22-25KG/Hr And is it a genuine sensor ? I also dont like the idea of cleaning them,I'd rather let the Gems ecu adapt with the sensor slowly degrading.
scott02464
Active Member
OK mate, Its deffo a genuine MAF sensor i didnt make a not of the readings. Is it pointing to a faulty MAF with the symptoms i have?
eightinavee
Well-Known Member
If the maf is reading low it really wont help.But its the misfire that is the key,esp if its on both banks.This is where using an oscilliscope on the plug leads and an infa red thermometer on the exhaust ports is really needed.
scott02464
Active Member
Right heres the outcome!
Had the Rangie on the computer (Autologic)
The O2 sensors were stuck on one reading, cant remember what but i think 4.98 volts. Was advised to replace.
So two new O2 sensors later and a reset of the fuel trims everything is looking peachy!!
Im now running on petrol until things settle in before i start using LPG again....
Before i was getting roughly around 12.5 MPG, now today iv been getting 23-26 MPG! Brilliant! This may also be down to changing plugs, leads, air filter, oils etc.
Thanks to everyone for your advice especially David Cooper and Eightinavee its all very much appreciated!
Regards, Scott
Had the Rangie on the computer (Autologic)
The O2 sensors were stuck on one reading, cant remember what but i think 4.98 volts. Was advised to replace.
So two new O2 sensors later and a reset of the fuel trims everything is looking peachy!!
Im now running on petrol until things settle in before i start using LPG again....
Before i was getting roughly around 12.5 MPG, now today iv been getting 23-26 MPG! Brilliant! This may also be down to changing plugs, leads, air filter, oils etc.
Thanks to everyone for your advice especially David Cooper and Eightinavee its all very much appreciated!
Regards, Scott
David_Cooper
Active Member
Brilliant news Scott, mine has been the same now for a few hundred miles and feels great! The car (and your bank balance..) will thank you for all the blood sweat and tears.
scott02464
Active Member
It's great mate! There has defiantly been blood, sweat and tears lol!
Are you getting the same kind of milage as me (18-26 mpg)
David_Cooper
Active Member
Mighty fine economy there! I'm not as good, I can see 21 or 22 ish on a run if i'm very carefull, 15 or 16 is the norm for me with the usual mix of round town and 'A' roads etc. Best thing is, emissions are now MoT passable
